Patent Publication Number: US-2022219338-A1

Title: Support device

Description:
TECHNICAL FIELD 
     The present disclosure relates to a support device, and more particularly, to a support device capable of supporting an object with a more appropriate supporting force. 
     BACKGROUND ART 
     Conventionally, in controlling support of an object, such as object gripping by a robot or the like or walking of a robot or the like, for example, it is necessary to control a contact force generated by contact with a surrounding environment or the object. However, in a case where a physical quantity of the environment or the object is unknown, it may be difficult to control the contact force. For example, in the gripping control, it is necessary to control a gripping force (supporting force) so as not to slip or break the object, but in a case of gripping an unknown object whose physical quantity (mass, center of gravity position, friction coefficient, and the like) is unknown, it is difficult to decide an appropriate gripping force. 
     Regarding such control of the supporting force, for example, a method of increasing or decreasing the gripping force according to a deviation amount of a pressure center position has been considered (see, for example, Patent Document 1). 
     CITATION LIST 
     Patent Document 
     
         
         Patent Document 1: Japanese Patent Application Laid-Open No. 2009-66714 
       
    
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     However, in the case of the method described in Patent Document 1, since the relationship between the deviation amount of the pressure center position and a slip is not clear, there is no guarantee that an object can be held with the minimum force. 
     The present disclosure has been made in view of such a situation, and enables an object to be supported with a more appropriate supporting force. 
     Solutions to Problems 
     A support device according to one aspect of the present technology is a support device including an elastic body that comes into contact with a supported object on at least a part of a surface of the elastic body, the surface having a plurality of curvatures different from each other, and a detection unit that detects information regarding a shear force of a portion of the surface of the elastic body, the portion being in contact with the object. 
     The support device according to one aspect of the present technology includes the elastic body that comes into contact with the supported object on at least a part of the surface of the elastic body, the surface having the plurality of curvatures different from each other, and the detection unit that detects the information regarding the shear force of the portion of the surface of the elastic body, the portion being in contact with the object. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a perspective view illustrating a configuration example of an embodiment of a gripping system. 
         FIG. 2  is a diagram for describing an initial slip. 
         FIG. 3  is a diagram for describing gripping force control. 
         FIG. 4  is a diagram for describing a sticking ratio. 
         FIG. 5  is a diagram for describing a contact curvature and the sticking ratio. 
         FIG. 6  is a diagram for describing a contact curved surface shape and the sticking ratio. 
         FIG. 7  is a diagram for describing the contact curved surface shape and the sticking ratio. 
         FIG. 8  is a diagram for describing a friction coefficient and the sticking ratio. 
         FIG. 9  is a diagram for describing a shear force distribution when the initial slip is generated. 
         FIG. 10  is a flowchart for describing an example of a procedure of a shear force distribution deriving process. 
         FIG. 11  is a diagram for describing calibration of the relationship between a shear displacement and a shear force. 
         FIG. 12  is a flowchart illustrating an example of a procedure of a shear force distribution adjusting process. 
         FIG. 13  is a diagram for describing a time-series change in the shear force. 
         FIG. 14  is a diagram for describing maximum pressure point measurement. 
         FIG. 15  is a diagram for describing the maximum pressure point measurement based on an image sensor. 
         FIG. 16  is a diagram for describing measurement of a contact region change. 
         FIG. 17  is a diagram describing measurement of the contact region change by tracking of a feature point. 
         FIG. 18  is a diagram for describing an example of a pressure distribution. 
         FIG. 19  is a diagram illustrating a main configuration example of a gripping device. 
         FIG. 20  is a diagram for describing a configuration example of a flexible deformation layer. 
         FIG. 21  is a diagram for describing a configuration example of the flexible deformation layer. 
         FIG. 22  is a diagram for describing a configuration example of the flexible deformation layer. 
         FIG. 23  is a diagram for describing an example of a method of measuring a rotational slip. 
         FIG. 24  is a diagram for describing a configuration example of the flexible deformation layer. 
         FIG. 25  is a diagram for describing a configuration example of the flexible deformation layer. 
         FIG. 26  is a diagram for describing a configuration example of the flexible deformation layer. 
         FIG. 27  is a block diagram illustrating a main configuration example of a control device. 
         FIG. 28  is a flowchart illustrating an example of a procedure of a control process. 
         FIG. 29  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 30  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 31  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 32  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 33  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 34  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 35  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 36  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 37  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 38  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 39  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 40  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 41  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 42  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 43  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 44  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 45  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 46  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 47  is a diagram for describing an example of how the friction coefficient is measured. 
         FIG. 48  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 49  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 50  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 51  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 52  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 53  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 54  is a diagram for describing an example of how a position and an orientation are detected. 
         FIG. 55  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 56  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 57  is a block diagram illustrating a main configuration example of the control device. 
         FIG. 58  is a flowchart illustrating an example of the procedure of the control process. 
         FIG. 59  is a block diagram illustrating a main configuration example of a computer. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
     Hereinafter, modes for carrying out the present disclosure (hereinafter, referred to as embodiments) will be described. Note that the description will be made in the following order. 
     1. First Embodiment (Gripping System and Gripping Force Control) 
     2. Second Embodiment (Configurations of Gripping Device and Flexible Deformation Layer) 
     3. Third Embodiment (Control Device and Control Process) 
     4. Appendix 
     1. First Embodiment 
     &lt;Gripping System&gt; 
       FIG. 1  is a perspective view illustrating a configuration example of an embodiment of a gripping system to which the present technology is applied. 
     A gripping system  100  is a system for gripping an object, and includes a control device  101  and a gripping device  102  as illustrated in  FIG. 1 . The control device  101  is communicably connected to the gripping device  102  and can control driving of the gripping device  102 . For example, the control device  101  can drive the gripping device  102  to grip the object, or can control a gripping force with which the gripping device  102  grips the object. The control device  101  can also acquire information obtained by the gripping device  102 . For example, the control device  101  can control driving of the gripping device  102  using the information acquired from the gripping device  102 . 
     The gripping device  102  performs a process related to gripping of the object. For example, the gripping device  102  is driven under the control of the control device  101 , and can grip the object with the gripping force designated by the control device  101 . 
     &lt;Initial Slip&gt; 
     In tasks of a robot, such as object gripping and walking, gripping, walking, and the like require control of a contact force generated by contact with a surrounding environment or the object. However, in a case where a physical quantity of the environment or the object is unknown, it is difficult to control the contact force. For example, in the gripping control, it is necessary to control the gripping force so as not to slip or break the object, but in a case of an unknown object whose physical quantity (mass, center of gravity position, friction coefficient, and the like) is unknown, it is difficult to decide an appropriate gripping force, which is a problem of robot control. 
     Regarding the problem, a phenomenon called “initial slip” is attracting attention. The initial slip is a phenomenon in which only a part of a contact surface slips, and is also called a precursory phenomenon of an overall slip. As illustrated in  FIG. 2 , when an initial slip region gradually expands and spreads to the entire contact region, the initial slip transitions to a generally called “slip” (also referred to as an overall slip), and a relative motion occurs between a device and the object or environment with which the device is in contact. 
     Here, “sticking” refers to a state where static friction is generated in the entire contact surface between a fingertip and the gripped object (the object gripped by the gripping device  102 ) and there is no relative motion between the fingertip and the gripped object. In addition, the “slip (overall slip)” refers to a state where dynamic friction is generated and there is a relative motion between two objects in contact with each other. Here, the “slip (overall slip)” refers to a slip in which the dynamic friction is generated in the entire contact surface between the fingertip and the gripped object and that involves the relative motion between the fingertip and the gripped object. 
     The “initial slip” is a phenomenon in which the dynamic friction is generated at a part of the contact surface between the fingertip and the gripped object, which is also referred to as a precursory phenomenon before the above-described slip (overall slip) is generated. It is said that the initial slip state exists during the transition from the “sticking” state to the “slip” state. In the case of the initial slip state, there is no relative motion between the fingertip and the gripped object. 
     For example, as illustrated in  FIG. 3 , if a gripping force f, which is a force acting in a normal direction perpendicular to the contact surface, is excessively large, the object is broken. In addition, if the gripping force f falls below an appropriate level, the “initial slip” is generated, and furthermore, if the gripping force f is insufficient, the “initial slip” develops to the “slip”, and the object cannot be gripped (is dropped). 
     That is, if the initial slip can be detected, it is possible to calculate the minimum gripping force that can hold the object without slipping, for example, in the gripping control. If the object can be gripped with the minimum gripping force, the possibility of breaking the object by gripping can be further suppressed. 
     However, the initial slip is a very minute change in the contact surface, and it is necessary to stably generate and detect the initial slip in order to detect the initial slip. In addition, it is necessary to quantify the degree of progress of the initial slip in order to control the degree of progress of the initial slip. Conventionally, a method for quantifying and stably detecting the initial slip and a configuration therefor have not been proposed. In addition, a control method using a detection result has not been proposed either. 
     Therefore, in order to stably detect and quantify the initial slip, there are proposed the shape and structure of a flexible deformation layer and a signal processing method of a tactile sensor. Furthermore, there is proposed a method of using the quantified initial slip for control. The gripping control will be described as an example for ease of description, but the present technology is not limited to this, and can be applied to general support control that handles contact with the environment, such as walking control. 
     &lt;Sticking Ratio&gt; 
     In order to control the initial slip, it is necessary to quantify the degree of the initial slip. Here, the contact region is divided into a “sticking region” where no initial slip is being generated (that is, a partial region where the static friction is being generated, which is included in the contact surface between the fingertip and the gripped object) and a “slip region” where the initial slip is being generated (that is, a partial region where the dynamic friction is being generated, which is included in the contact surface between the fingertip and the gripped object). The degree of slip can be indicated by a ratio between these two regions. Here, the ratio of the sticking region to the contact region is defined as “sticking ratio”. In a case where the sticking ratio is 1 (=100%), the contact region has no slip region and is completely stuck. On the other hand, in a case where the sticking ratio is 0, the entire contact region is the slip region, and the contact region is in a state where the slip (overall slip) is being generated. 
     C of  FIG. 4  illustrates an example of a result of performing finite element method (FEM) analysis, for example, under conditions corresponding to a case where a spherical object is gripped by a flat fingertip as illustrated in A of  FIG. 4  or a case where a flat object is gripped by a curved fingertip as illustrated in B of  FIG. 4 . C of  FIG. 4  illustrates how the sticking ratio (slip region/sticking region) in the contact surface changes. Regions illustrated in dark gray indicate the sticking region, and regions illustrated in light gray indicate the slip region. As a shear force F X  (unit: Newton (N)), which is a force acting in a shear direction, increases, the slip region spreads from a periphery of the contact surface, and when the sticking ratio reaches 0%, the entire region transitions to the slip region. Therefore, it can be said that, in order to grip the object without slipping, the gripping force is only required to be adjusted to such an extent that the sticking ratio does not reach 0%. 
     Here, the “shear direction” is a direction orthogonal to the normal direction and indicates a direction parallel to the contact surface. The shear direction is the same as a direction in which the slip is generated. 
     &lt;Contact Curvature and Sticking Ratio&gt; 
     In order to investigate the relationship between the change in the sticking ratio and the contact condition, an analysis was performed on the basis of a simple elastic contact model illustrated in A of  FIG. 5  and B of  FIG. 5 . As a result, it was found that the change in the sticking ratio varies depending on the “shape of a contact curved surface” and a “friction coefficient”. 
     &lt;Contact Curved Surface Shape and Sticking Ratio&gt; 
     A curvature of the contact curved surface was changed as in a graph illustrated in A of  FIG. 6 , and the state of the change in the sticking ratio relative to the shear force F X  was plotted as in a graph illustrated in B of  FIG. 6  for each curvature. 
     Here, the curvature is an amount representing the degree of curve of a line or a surface. The curvature increases as the degree of curve is sharper. More specifically, the curvature is a reciprocal of a radius of curvature. One of methods for representing a curved surface is a higher-order function of y=x n . A curve of the higher-order function is represented by the curved surface, so that the curve can be mathematically analyzed. In this case, when an order n of the function is increased, the curved surface becomes gentler (gradient is small) in a range of 0&lt;x&lt;1. Thus, the curvature decreases as the order of the contact surface is higher. If the curved surface is represented mathematically such as by the higher-order function, the curvature can be replaced with the order of the function. 
     The contact curved surface is assumed to be a linear function (a cone in three dimensions) or a higher-order curve. In the graph in A of  FIG. 6 , a thicker line indicates a curved surface having a higher order. As illustrated in this graph, the curved surface is gentler as the order increases. Also in the graph of B of  FIG. 6 , a thicker line indicates a curved surface having a higher order. As illustrated in this graph, as the curved surface is gentler, the sticking ratio tends to decrease rapidly when the shear force is increased to some extent. This is because, when the contact is made with the curved surface, a contact pressure has a distribution varying from place to place, and the initial slip is gradually generated from a portion where the pressure is weak. That is, the contact pressure is more uniform as the curved surface is gentler, and the progress of the initial slip is faster. 
     In addition, the rate of the change in the sticking ratio increases as the curved surface is steeper while the rate decreases as the curved surface is gentler and the sticking ratio rapidly decreases to  0  at a certain point. In general, a detection accuracy is higher as the rate of the change is higher. Therefore, it can be said that the detection accuracy of the sticking ratio increases as the curved surface is steeper. 
     Here, the contact curved surface represents a contact surface between a robot fingertip and an object in robot gripping. This contact surface is a relative surface shape, and, for example, the same result is obtained in a case where a spherical fingertip and a flat object are in contact with each other and in a case where a flat fingertip and a spherical object are in contact with each other. 
     For example, a contact shape in which a flat surface and a curved surface are mixed is considered. In the case of such a contact curved surface in which the flat surface and the curved surface are mixed, the sticking ratio changes as illustrated in a graph of  FIG. 7  according to the magnitude of the shear force. In this graph, the sticking ratio rapidly decreases as the shear force increases to some extent, for example, as in a portion surrounded by an ellipse. 
     The magnitude of the shear force when the sticking ratio rapidly decreases depends on a flat surface mixture rate of the contact surface. In  FIG. 7 , a thicker line indicates the change in the sticking ratio in the contact surface having a higher rate of the curved surface (having a lower flat surface mixture rate). That is, as the flat surface mixture rate of the contact surface increases, the sticking ratio rapidly decreases at a smaller shear force. 
     This shows that the initial slip spreads from the periphery of the contact surface, and the overall slip is generated at the moment when the initial slip reaches the flat surface portion. This result also shows that the contact with the curved surface enables stable control of the sticking ratio. Conversely, as long as the progress of the initial slip can be controlled so as not to reach the flat surface portion, there is no problem even if the flat surface portion exists. If the flat surface portion is increased, a contact area can be increased, and an orientation stability of the object being gripped is improved. 
     &lt;Friction Coefficient and Sticking Ratio&gt; 
     The change in the sticking ratio depends not only on the shape of the contact curved surface but also on the friction coefficient. A graph illustrated in  FIG. 8  is a graph obtained by plotting the change in the sticking ratio in a case where the contact is made at different friction coefficients. As illustrated in this graph, as the friction coefficient is lower, a decrease speed of the sticking ratio is faster. In a case where the friction coefficient is known in advance, or in a case where the friction coefficient can be measured, the shear force can be controlled more easily according to the change in the sticking ratio corresponding to the friction coefficient. In addition, in a case where the friction coefficient is unknown, the sticking ratio is not uniquely determined. Therefore, if a decrease in the sticking ratio can be detected and control can be performed so that the sticking ratio is maintained at 100%, the object can be gripped with the minimum force without being slipped off. 
     &lt;Relationship Between Contact Curved Surface Shape/Friction Coefficient and Sticking Ratio&gt; 
     As described above, the change in the sticking ratio greatly varies depending on the shape of the contact surface (curvature and curved surface/flat surface). In particular, a flat surface or a gently curved surface having a small curvature easily causes a rapid decrease in the sticking ratio. Therefore, if the curved surface is formed with a certain degree of curvature, more stable control can be achieved. 
     However, the magnitude of the curvature and the contact area are in a trade-off relationship. For example, when the curvature is increased to suppress the rapid decrease in the sticking ratio, the contact area with the object is reduced, which can improve a slip detection accuracy, but conversely, tends to cause an unstable state. 
     In other words, if the fingertip is formed in a curved surface and the shape thereof is adjusted, the change in the sticking ratio can be freely designed. Therefore, the control is only required to be performed on the basis of the change in the sticking ratio associated with the fingertip shape. The trade-off between the curvature and the contact area can be handled if a plurality of curved surfaces is used or the curved surface is changed according to application. 
     The change in the sticking ratio also depends on the friction coefficient. In the case where the friction coefficient is known in advance, the change in the sticking ratio can be known in advance from information regarding the contact curved surface, and thus the control can be performed by use of the relationship between the friction coefficient and the sticking ratio. Even if the friction coefficient is not known in advance, the control can be performed if a sticking ratio change model is estimated or a premise is made. 
     &lt;Method of Measuring Sticking Ratio&gt; 
     As described above, the change in the sticking ratio depends on the “shape of the contact curved surface” and the “friction coefficient”. The shape of the contact curved surface can be roughly estimated if the curved surface shape of the fingertip is grasped in advance. However, the friction coefficient is often unknown, and although the friction coefficient can be estimated in advance, it is difficult to obtain an accurate value due to problems of accuracy and the like. In a case of a conventional method, it is difficult to measure the sticking ratio. Therefore, a shear displacement and a shear force distribution are focused on so that the sticking ratio is derived. 
     &lt;Method 1: Method Using Shear Displacement&gt; 
     A sticking ratio R stic  is a value depending on a friction coefficient μ, the shear force F X  acting on the object, a gripping force F N , and the shape of the contact curved surface (the curvature or the order of the curved surface) n, and is derived by the following equation (1). 
       [Math. 1] 
         R   stic =1− f (μ, F   X   ,F   N   ,n )  (1)
 
     Here, the shear force F X  acting on the object is derived by the following equation (2) by use of a shear displacement u X  of the fingertip and a contact area S under a condition where no dynamic friction is being generated. 
       [Math. 2] 
         F   X   =g ( S,u   X )  (2)
 
     If the contact surface is a curved surface and the information n regarding the curved surface (curvature and curved surface/flat surface) is known, a relationship derived from a contact model h is derived between the contact area S, the gripping force F N , and the curved surface information n, as in the following equation (3). As the contact model, a generally proposed elastic contact model (Hertz) may be used. 
       [Math. 3] 
         S=h ( F   N   ,n )  (3)
 
     When the above relationship is used, the sticking ratio R stic  can be derived as the following equation (4). 
       [Math. 4] 
         R   stic =1−ψ(μ, F   N   ,n )·Θ( u   X )  (4)
 
     This relational expression means that the sticking ratio can be expressed in a form using a function θ ( u   X ), which does not depend on the unknown friction coefficient μ. Therefore, the sticking ratio can be controlled if the shear displacement u X  is measured and controlled. For example, even if the friction coefficient is unknown, the sticking ratio can be maintained at 100% if u X  is set to, for example, 0. In addition, assuming that the friction coefficient is also in a certain range makes it possible to control the sticking ratio in a certain range width similarly, by use of u X . 
     &lt;Method 2: Method Using Shear Displacement Distribution and Shear Force Distribution&gt; 
     In a case where a distribution of the shear displacement and a distribution of the shear force are obtained, the sticking ratio can be obtained as an absolute value even if the friction coefficient is unknown. For example, the shear force distribution in the contact surface in a situation where the initial slip is being generated is as illustrated in a graph of  FIG. 9 . As illustrated in  FIG. 9 , the shear force is discontinuous at a boundary between the slip region and the sticking region. If this discontinuous point is detected, the ratio of the sticking region can be calculated and the sticking ratio can be obtained. This discontinuous point exists for any friction coefficient. 
     Examples of a method of detecting the discontinuous point include the following methods.
         Using a general image processing filter (detecting an edge by use of a differential filter or the like)   Obtaining a gradient of the shear force, and considering a portion where a sign of the gradient is switched as the discontinuous point       

     Note that the same applies to the shear displacement. The “shear displacement” is a deformation amount in the shear direction. As a unit of the shear displacement, a unit of length (for example, meters, millimeters, or the like) is used. That is, the “shear displacement” refers to the deformation amount of the object in the shear direction caused by the shear force acting on the object. Even if the same shear force is applied, the shear displacement varies depending on the rigidity of the object (the harder the object, the smaller the shear displacement). 
     For obtaining the shear force distribution, a sensor capable of measuring the distribution of the shear force may be used, or a sensor capable of measuring the distribution of the shear displacement may be used to convert the shear displacement into the shear force. An example of a procedure of a shear force distribution deriving process executed to derive the shear force distribution in this case will be described with reference to a flowchart of  FIG. 10 . 
     When the shear force distribution deriving process is started, in step S 101 , the control device  101  controls the gripping device  102 , causes the gripping device  102  to detect the shear displacement, and calculates a shear displacement amount at each point. 
     In step S 102 , the control device  101  converts the shear displacement amount into the shear force. 
     In step S 103 , the control device  101  determines whether or not the process has been performed for all points. In a case where it is determined that there is an unprocessed point, the process returns to step S 101 , and the subsequent processes are repeated. That is, respective processes of steps S 101  to S 103  are executed for all points. Then, in a case where it is determined in step  3103  that the process has been performed for all points, the process proceeds to step S 104 . 
     In step  3104 , the control device  101  aggregates and stores the information on the points of all nodes. When the process of step  3104  ends, the shear force distribution deriving process ends. 
     When the shear displacement is converted into the shear force in this way, the relationship between the shear displacement and the shear force may be calibrated in advance. As a calibration method, for example, as illustrated in  FIG. 11 , a method of pressing a detection node  151  against a horizontal surface  152  or the like to acquire a sensor value can be considered. An example of a procedure of the shear force distribution deriving process executed to perform such calibration will be described with reference to a flowchart of  FIG. 12 . 
     When the shear force distribution deriving process is started, in step S 151 , the control device  101  controls the gripping device  102  to press each uneven surface of the detection node  151  against the horizontal surface  152 . 
     In step S 152 , the control device  101  controls the gripping device  102  to acquire sensor values of all the nodes. 
     In step S 153 , the control device  101  determines whether or not data of the sensor values is stable. In a case where it is determined that the data is not stable, the process returns to step S 152 . The processes of steps S 152  and S 153  are repeated until the data is stable. Then, in a case where it is determined in step S 153  that the data is stable, the process proceeds to step S 154 . 
     In step S 154 , the control device  101  stores the sensor values. When the process of step S 154  ends, the shear force distribution deriving process ends. 
     &lt;Method 3: Method Using Temporal Change in Shear Displacement Distribution and Shear Force Distribution&gt; 
     “Method 2” described above is a method of obtaining the sticking ratio from distribution information of the shear displacement and the shear force at a certain time. In addition, the sticking ratio can be obtained from a temporal change in the distribution information. 
     For example, in the slip region, a phenomenon called a stick-slip phenomenon in which the “slip” and the “sticking” are repeated may be generated. When the phenomenon is generated, a change as illustrated in a graph in A of  FIG. 13  is observed as the temporal change in the shear displacement and the shear force in the slip region. If the discontinuous change on the time axis is measured, it is possible to determine whether an observation point is the slip region or the sticking region. 
     In addition, since the dynamic friction is generated in the slip region, the shear force and the shear displacement may have constant values according to Coulomb&#39;s law. When the phenomenon is generated, a change as illustrated in B of  FIG. 13  is observed, in which the change becomes constant when the sticking state transitions to the slip state. If the change on the time axis is measured, it is possible to determine whether the observation point is the slip region or the sticking region. 
     If the above process is repeatedly performed at all observation points in the contact region, the ratio of the sticking region can be calculated, and the sticking ratio can be measured. 
     &lt;Fusion Between Method 1 and Method 2 (or Method 3)&gt; 
     In the case of Method 1, the change in the sticking ratio is predicted from the information regarding the curvature or shape of the contact surface or the like, and the gripping force is controlled. In the case of Method 2, the sticking ratio is obtained from the actual measurement results. That is, it can be said that Method 1 is a feedforward method that predicts the change in the sticking ratio in advance, and Method 2 is a feedback method using the actual measurement results. Therefore, if both of these methods are combined for performing control, it is possible to perform control robust against a modeling error between model information of the contact surface and the actual contact surface, and to improve responsiveness by the prediction of the sticking ratio. Since Method 3 can also be said to be a feedback method like Method 2, Method 1 and Method 3 can also be combined in a similar manner. 
     Specific Example of Method of Measuring Shear Displacement Amount 
     &lt;Method Based on Pressure Distribution Sensor&gt; 
     When a flexible deformation layer (a contact portion in contact with the gripped object) of the fingertip is deformed in the shear direction, a pressure distribution changes similarly. Therefore, the change in the pressure distribution is detected so that the shear displacement can be measured. Examples of a method of detecting the change in the pressure distribution include the following methods. 
     Measurement of CoP Movement Amount (Method of Obtaining Center of Pressure) 
     The center of pressure is a center point of the pressure distribution, and is defined by the following equation (5). 
     
       
         
           
             
               
                 
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     A CoP movement amount (Δx cop ) before and after occurrence of shearing is calculated, and the calculated value is used as the shear displacement amount (u X ). The CoP is a pressure center value, and is a point of action of a force in a case where pressures distributed with a spatial extent are collectively expressed as one force. A unit of the CoP movement amount is a unit of length (for example, m or the like). In many cases, the Cop is obtained as coordinates. The Cop is a concept similar to the center of gravity. In addition, in the equation (5), in a case where u X  and Δx cop  do not match, correction may be performed by use of a correction coefficient or correction function or the like. 
     Maximum Pressure Point 
     The displacement in the shear direction is calculated from coordinates of the maximum pressure value. For example, as illustrated in A of  FIG. 14 , when a flexible deformation layer  161  is deformed by coming into contact with an object  162 , the position of the maximum pressure point in the pressure distribution generated by the contact of the object  162  changes. Therefore, as illustrated in B of  FIG. 14 , a displacement  163  of the maximum pressure point is obtained as the displacement in the shear direction. Note that the maximum pressure is susceptible to noise, a filter generally used in image processing, such as an averaging filter, may be used, for example. 
     &lt;Method Based on Image Sensor&gt; 
     As illustrated in  FIG. 15 , in a case of a sensor of a type in which the contact surface is imaged by a camera or the like, the shear displacement can be detected by the following methods. 
     Method of Calculating Movement Amount of Entire Contact Region 
     The contact region can be distinguished from a non-contact region by use of a change in color or texture or the like. Therefore, as in an example illustrated in  FIG. 16 , a movement amount of an entire contact region  171  is obtained, so that the shear displacement amount can be calculated. 
     Feature Point Tracking Method 
     As illustrated in  FIG. 17 , tracking a feature point of a surface of the gripped object on the contact surface or tracking a marker  172 , a scale, or the like provided in advance in the flexible deformation layer makes it possible to detect the shear displacement. 
     In a case where the shear displacement is obtained by the above methods, the accuracy can be further improved if the contact surface is formed in a curved surface. For example, as illustrated in  FIG. 18 , comparing the pressure distribution at the time of flat surface contact with the pressure distribution at the time of curved surface contact, the pressure distribution in the case of the flat surface contact is more unstable depending on a contact state than in the case of the curved surface contact, and there is a possibility that the shear displacement cannot be stably measured. 
     2. Second Embodiment 
     &lt;Gripping Device&gt; 
     A of  FIG. 19  illustrates a main configuration example of the gripping device  102 , which is an embodiment of a support device to which the present technology is applied. As illustrated in A of  FIG. 19 , the gripping device  102  includes finger portions  201 A and  201 B, and can grip an object using these portions. Hereinafter, the finger portions  201 A and  201 B will be referred to as a finger portion  201  in a case where it is not necessary to distinguish the finger portions  201 A and  201 B from each other for description. Here, the description will be made assuming that the gripping device  102  includes two finger portions  201 , but the gripping device  102  may include any number (for example, three or more) of finger portions  201 . 
     The finger portion  201 A is provided with a sensor  211 A and a flexible deformation layer  212 A. Similarly, the finger portion  201 B is provided with a sensor  211 B and a flexible deformation layer  212 B. The sensors  211 A and  211 B are referred to as a sensor  211  in a case where it is not necessary to distinguish the sensors  211 A and  211 B from each other for description. In addition, the flexible deformation layers  212 A and  212 B will be referred to as a flexible deformation layer  212  in a case where it is not necessary to distinguish the flexible deformation layers  212 A and  212 B from each other for description. That is, the sensor  211  and the flexible deformation layer  212  are formed on each of the plurality of finger portions that grips the object. 
     The sensor  211  can include any sensing device such as a pressure sensor or an image sensor, for example, and can detect any information corresponding to the sensing device. For example, the sensor  211  detects information regarding a shear force of a portion of a surface of the flexible deformation layer  212  in contact with the object. 
     For example, the sensor  211 A detects predetermined information (information detectable by the sensing device) regarding a contact surface between the flexible deformation layer  212 A and the object by using the sensing device. Furthermore, for example, the sensor  211 B detects predetermined information (information detectable by the sensing device) regarding a contact surface between the flexible deformation layer  212 B and the object by using the sensing device. 
     Each of the sensors  211  is communicably connected to the control device  101  by a circuit (not illustrated) or the like, and supplies the detected information to the control device  101 . 
     The flexible deformation layer  212  is an elastic body that comes into contact with the supported object on at least a part of the surface of the flexible deformation layer  212 . As described in the first embodiment, the rate of change in the sticking ratio varies depending on the curvature or shape of the curved surface. Using an elastic body having a plurality of curvatures and shapes by making use of this property makes it possible to design a sticking ratio measurement accuracy required for operation or application. 
     When the object gripping is classified by rough gripping forms, the object gripping is classified into two types: a power grip for performing gripping so as to clasp an object  231  as illustrated in C of  FIG. 19 , and a precision grip (fingertip grip) for performing gripping so as to pinch the object  231  as illustrated in B of  FIG. 19 . The power grip is used in a case where the gripped object has a high mass or in a case where it is necessary to support a moment acting on the object as in a handle portion of a frying pan, for example. Therefore, the portion of the surface of the flexible deformation layer  212  that comes into contact with the object at the time of power grip is configured by a curved surface having a small curvature so that the contact area tends to be large. 
     On the other hand, the precision grip can measure and grip the object with higher accuracy. For example, the precision grip is used in a case where a very soft and brittle object or the like is gripped. Therefore, the portion of the surface of the flexible deformation layer  212  that comes into contact with the object at the time of precision grip is configured by a curved surface having a large curvature so that the contact area tends to be small. 
     That is, the surface of the flexible deformation layer  212  has the plurality of curvatures different from each other (is configured by the plurality of curvatures). For example, a surface of the flexible deformation layer  212  around a fingertip of the finger portion  201  is formed with a curved surface having a large curvature for the precision grip, and a surface of the flexible deformation layer  212  at a pad portion of the finger portion  201  is formed with a curved surface having a small curvature. With such a configuration, the flexible deformation layer  212  can cope with gripping of both the power grip and the precision grip. Such a configuration makes it possible to suppress a decrease in the detection accuracy of the sticking ratio in the precision grip, and also makes it possible to suppress a reduction in the contact area in the power grip. Needless to say, the surface of the flexible deformation layer  212  may have three or more kinds of curvatures. That is, it is possible to cope with more various gripping methods. In addition, fingertips having different curvatures may be mounted on different fingers. It is conceivable to perform control such as changing the finger to be used depending on the gripped object. 
     Modified Example 
     For example, as in an example illustrated in A of  FIG. 20 , the flexible deformation layer  212  may be laminated on the sensor  211 . In this case, it is sufficient that the sensor  211  can obtain information regarding the contact portion between the flexible deformation layer  212  and the object (for example, information regarding the shear force) via the flexible deformation layer  212 . For example, in a case where the sensor  211  detects the information regarding the contact portion using the image sensor, it is sufficient that a transparent material is used for the flexible deformation layer  212  so that the image sensor can image the state of the contact portion via the transparent flexible deformation layer  212 . With such a configuration, the control device  101  can stably determine the slip region and the sticking region, and the gripping device  102  can grip the object with the minimum force without slipping. Needless to say, the flexible deformation layer  212  does not have to be laminated on the sensor  211 , and the sensor  211  may detect the information regarding the contact portion without interposing the flexible deformation layer  212 . 
     Furthermore, as in an example illustrated in B of  FIG. 20 , the surface of the flexible deformation layer  212  may be configured by a flat surface and a curved surface. Such a configuration makes it possible to determine the slip region and the sticking region without reducing the contact area (while keeping the contact area large). Note that, as in an example illustrated in C of  FIG. 20 , the surface of the flexible deformation layer  212  may be calibrated in a conical shape. 
     Furthermore, as in an example illustrated in D of  FIG. 20 , the surface of the flexible deformation layer  212  may be configured by a surface having an unevenness (jagged surface) and a curved surface. Such a configuration makes it possible to detect the change in the sticking ratio while a reduction in the friction coefficient is suppressed. 
     In addition, the surface of the flexible deformation layer  212  may have a curvature corresponding to a direction. For example, the surface of the flexible deformation layer  212  may have a predetermined curvature only in a predetermined direction as in an example illustrated in A of  FIG. 21 . In the case of A of  FIG. 21 , the surface of the flexible deformation layer  212  is configured in a semi-cylindrical shape and has a predetermined curvature in a direction perpendicular to a longitudinal direction of the semi-cylindrical shape (a slip direction indicated by an arrow in the drawing). In a case where the flexible deformation layer  212  having such a shape detects a slip in the predetermined direction (slip direction), the slip detection accuracy can be improved as compared with other directions. 
     Therefore, for example, it is possible to perform an operation of making contact without slipping the object in a specific direction or an operation of slipping the object in a specific direction. In addition, since the shape of the flexible deformation layer  212  is simpler, the flexible deformation layer  212  can be more easily manufactured. Furthermore, an increase in manufacturing cost can be further suppressed. 
     Furthermore, as in an example illustrated in B of  FIG. 21 , a portion of the surface of the flexible deformation layer  212  that may come into contact with the object may have a plurality of curvatures different from each other. With such a configuration, the slip detection accuracy and the extent of the contact area can be adjusted according to a dynamic range of the gripping force. For example, in the configuration as illustrated in B of  FIG. 21 , the slip detection accuracy can be improved in a portion where the gripping force is small, and conversely, the reduction in the contact area can be suppressed in a portion where the gripping force is large. 
     Furthermore, as in examples illustrated in C and D of  FIG. 21 , the sensor  211  may be arranged in a curved surface shape. In the case of the example in C of FIG.  21 , the sensor  211  is laminated on the flexible deformation layer  212  having a curved surface. In addition, in the case of the example of D of  FIG. 21 , the sensor  211  is arranged in a curved surface shape, and the flexible deformation layer  212  is laminated thereon. With such a configuration, the contact object or the environment comes into direct contact with the sensor, and thus, the slip detection can be performed more accurately. 
     Furthermore, the hardness of the flexible deformation layer  212  may be non-uniform. That is, the hardness of the flexible deformation layer  212  may vary from place to place. For example, as illustrated in A of  FIG. 22 , the flexible deformation layer  212  may be divided into three in a vertical direction, and the hardness of flexible deformation layers  212 - 1  and  212 - 3  may be higher than the hardness of a flexible deformation layer  212 - 2  (the hardness of the flexible deformation layer  212 - 2  may be lower than the hardness of the flexible deformation layers  212 - 1  and  212 - 2 ). Furthermore, for example, as illustrated in B of  FIG. 22 , the hardness of a central portion of the flexible deformation layer  212  (flexible deformation layer  212 - 4 ) may be lower than the hardness of a peripheral portion of the flexible deformation layer  212  (flexible deformation layer  212 - 5 ). Furthermore, as illustrated in C of  FIG. 22 , the flexible deformation layer  212  may be divided into three in a horizontal direction, a flexible deformation layer  212 - 6  may have the lowest hardness, a flexible deformation layer  212 - 8  may have the highest hardness, and a flexible deformation layer  212 - 7  may have a hardness therebetween. 
     Such a configuration makes it possible to widen dynamic ranges of the gripping force and the shear force, in which a slip can be detected. In addition, the slip detection accuracy (sensitivity) can be adjusted according to the ranges of the gripping force and the shear force. As a result, a mass range of a grippable object can be finally widened. 
     As illustrated in D of  FIG. 22 , in a case where the flexible deformation layer with a uniform hardness is brought into contact with the object, there is a possibility that the shear displacement amount of the flexible deformation layer may be saturated at a certain shear force or more, and a slip cannot be detected with a force equal to or larger than the shear force. If the hardness is changed, the shear displacement amount of the flexible deformation layer can be adjusted according to the range of the force, and thus the dynamic range can be widened. 
     &lt;Plurality of Curved Surfaces&gt; 
     The above method can detect a slip in a translation direction, but it is difficult to detect a slip in a rotation direction. This is because it is difficult to detect the shear displacement amount in the rotation direction even if the slip in the rotation direction is generated. Therefore, as in an example illustrated in A of  FIG. 23 , the shape of the surface of the flexible deformation layer  212  may be a shape in which a plurality of curved surfaces is arranged. As illustrated in A of  FIG. 23 , in this case, the flexible deformation layer  212  is configured by a flat surface portion and a plurality of curved surface portions  212 R protruding from the flat surface portion. 
     The pressure distribution when the flexible deformation layer  212  having such a shape comes into contact with the object is represented by a pressure contour diagram as illustrated in B of  FIG. 23 . This pressure contour diagram illustrates, as an example, a case where the number of the curved surface portions  212 R is four (2×2). Coordinates of a center of pressure point in each of the curved surface portions  212 R are represented by (x 1 , y 1 ). 
     Here, when a moment is applied to the object and the initial slip starts to be generated in the rotation direction, the center of pressure point in each of the curved surface portions  212 R moves as in a pressure contour diagram in C of  FIG. 23 . Coordinates of each center of pressure point after the movement are expressed as (x 1 ′, y 1 ′). 
     The relationship between the CoP positions before and after the rotation and the shear displacement can be expressed as the following expression (6), where the shear displacement amount in the rotation direction is 0 and the shear displacement amount in the translation direction is (t x , t y ). 
     
       
         
           
             
               
                 
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     This relational expression is derived for the number of the curved surface portions  212 R, and the unknowns θ, t x , and t y  can be obtained from results of the derivation. Specific examples of the method include a least squares method or the like. With this method, the shear displacement amount in the rotation direction can be obtained, and thus the sticking ratios in rotation and translation can be measured simultaneously. 
     Modified Example 
     For example, as illustrated in A of  FIG. 24 , the plurality of portions  212 R each having a curved surface, which is included in the flexible deformation layer  212 , may be laminated on the sensor  211 . Such a configuration makes it possible to detect the rotational slip as described above. In addition, since the gripping force control can be performed on the basis of information regarding the rotation direction, it is possible to achieve more accurate gripping force control. 
     Furthermore, for example, as illustrated in B of  FIG. 24 , the surface of the flexible deformation layer  212  may be configured by a flat surface portion and the plurality of curved surface portions  212 R protruding from the flat surface portion. With such a configuration, since a space among the plurality of curved surface portions  212 R is filled with the flat surface portion, the distance between the curved surface portions  212 R is less likely to change. Therefore, the slip detection accuracy can be improved. In addition, since the plurality of curved surface portions  212 R is coupled to one flexible layer, it is possible to more easily suppress an increase in positional deviation at the time of mounting. As a result, the slip detection accuracy can be improved. 
     Furthermore, for example, as illustrated in C of  FIG. 24 , the surface of the flexible deformation layer  212  may be configured by a first curved surface portion having a first curvature and a plurality of second curved surface portions each protruding from the first curved surface portion and each having a second curvature larger than the first curvature. With such a configuration, an envelope surface obtained by connecting vertices of the plurality of curved surface portions  212 R is a curved surface. Therefore, a difference in the contact pressure is generated in the contact region, and the slip detection accuracy can be improved. 
     Furthermore, for example, as illustrated in D of  FIG. 24 , a flexible deformation layer  212 S having another hardness may cover the plurality of curved surface portions  212 R so as to include the plurality of curved surface portions  212 R. In the case of the example of D of  FIG. 24 , curved surface portions  212 R- 1 ,  212 R- 2 , and  212 R- 3  are covered with the flexible deformation layer  212 S having a hardness different from the hardness of the curved surface portions so that the flexible deformation layer  212 S includes the curved surface portions. 
     With such a configuration, the plurality of curved surface portions  212 R does not come into direct contact with the object or the surrounding environment, and thus, wear of the curved surface portions  212 R can be pushed. In addition, since the curved surface comes into contact with the object, a difference in the contact pressure is generated in the contact region, and the slip detection accuracy can be improved. 
     Furthermore, for example, as illustrated in A of  FIG. 25  and B of  FIG. 25 , another flexible deformation layer  212 S having a curved surface may be laminated on the plurality of curved surface portions  212 R. With such a configuration, contact with the object or another environment is the curved surface contact while the rotational slip is detected, and thus, the slip detection can be performed more stably. 
     That is, the flexible deformation layer  212  may include a plurality of first elastic bodies each having a surface with a first curvature and a second elastic body superposed on the plurality of first elastic bodies and having a surface with a second curvature. Furthermore, the hardness of the first elastic bodies may be different from the hardness of the second elastic body. 
     In addition, as in an example illustrated in C of  FIG. 25 , the hardnesses of the plurality of curved surface portions  212 R may be changed from place to place. In C of  FIG. 25 , respective hardnesses of the curved surface portions  212 R- 1  to  212 R- 3  are not unified (the curved surface portions  212 R having hardnesses different from each other are included). That is, the plurality of elastic bodies having curved surfaces may have hardnesses different from each other. 
     Furthermore, as in an example illustrated in D of  FIG. 25 , a plurality of curved surface flexible deformation layers may be arranged so that the plurality of curved surface flexible deformation layers is sandwiched from above and below and curved surface portions do not overlap each other. In D of  FIG. 25 , on the flexible deformation layer  212  having the plurality of curved surface portions  212 R, the flexible deformation layer  212 S having a similar shape is laminated with the directions thereof turned upside down. That is, the second elastic body has a surface having the first curvature in a direction opposite to a direction of the surface of each first elastic body with the first curvature. With such a configuration, a curved surface portion  212 SR of the flexible deformation layer  212 S is positioned between the curved surface portions  212 R- 1  and  212 R- 2 . As a result, since a spatial density of the flexible deformation layer can be increased, the number of detection points of the shear displacement increases, and the slip detection can be performed more accurately. 
     Furthermore, as in an example illustrated in A of  FIG. 26 , the hardness of the flexible deformation layer  212  may be locally changed. In  FIG. 26 , portions  212 - 1  indicated by diagonal line patterns, which are included in the flexible deformation layer  212 , are set to have a higher hardness than a portion  212 - 2  indicated by a white background. A cross-sectional view taken along a dotted line A-A′ in A of  FIG. 26  is illustrated in B of  FIG. 26 . As illustrated in the cross-sectional view in B of  FIG. 26 , the portion  212 - 2  having a higher hardness than the portions  212 - 1  is formed from the surface to the side of the sensor  211 . As described above, the flexible deformation layer  212  may have a plurality of local portions having a higher hardness than a hardness of a surrounding portion. Such a configuration makes it possible to detect the rotational slip without explicitly forming a plurality of curved surface flexible deformation layers. In addition, since an uneven shape is not formed, it is possible to reduce the possibility that each of the curved surface flexible deformation layers may be broken, for example, by being caught, which can improve the durability of the flexible deformation layer  212 . 
     Furthermore, as in an example illustrated in C of  FIG. 26 , the height of an unevenness may be changed depending from place to place, and an envelope surface may be a curved surface. The envelope surface indicates a surface provided so as to be in contact with all of a plurality of curves arranged in a space. In this case, if there is a curved surface or a flat surface passing through all vertexes of the curved surface portions  212 R in the flexible deformation layer  212  in which the plurality of curved surface portions  212 R (uneven shape) is arranged, the curved surface or the flat surface is referred to as the envelope surface. In the case of the example in C of  FIG. 26 , the curved surface portion  212 R- 2  is higher than the curved surface portions  212 R- 2  and  212 R- 3 , and an envelope surface  251  in contact with the curved surface portions (a surface indicated by a dotted line in  FIG. 26 ) is formed in a curved surface shape. That is, the heights of the curved surface portions  212 R are different from each other. 
     With such a configuration, when the contact with the object is made, the pressure detected on the unevenness has a value corresponding to the curved surface contact (in the case of the example of C of  FIG. 26 , the pressure is higher in the central portion and lower toward the periphery), and there is a difference in the contact pressure, which can improve the detection accuracy of the initial slip. 
     Furthermore, as in an example illustrated in D of  FIG. 26 , each of the curved surface portions  212 R of the flexible deformation layer  212  may be formed at a position based on a predetermined regularity. In addition, as in the example illustrated in E of  FIG. 26 , each of the curved surface portions  212 R of the flexible deformation layer  212  may be formed at any position. 
     The position of the curved surface flexible deformation layer is not limited in design, and is flexible with respect to an attachment position and the shape. In addition, if the density of the curved surface flexible deformation layer is changed from place to place, the slip detection accuracy can be flexibly changed according to the place, which enables a calculation load to be distributed. 
     Note that the above-described examples can be appropriately combined and used. For example, a modified example of a single curved surface and a modified example of a plurality of curved surfaces may be used in combination with each other. 
     3. Third Embodiment 
     &lt;Case where Friction Coefficient is not Known in Advance&gt; 
     &lt;Control Device&gt; 
     Next, the control device  101  will be described. In a case where the friction coefficient is not known in advance, the control device  101  is only required to calculate the shear displacement amount and control the gripping force so that the shear displacement is zero. In this manner, the object can be gripped without slipping. 
       FIG. 27  illustrates a main configuration example of the control device  101  in this case. In the case of the example of  FIG. 27 , the control device  101  includes a shear displacement amount detection unit  301 , a shear displacement amount calculation unit  302 , a gripping force calculation unit  303 , and an actuator control unit  304 . 
     When the gripping device  102  grips the object, the shear displacement amount detection unit  301  performs a process related to detection of information regarding a shear force generated between the surface of the flexible deformation layer  212  of the gripping device  102 , which is the contact portion in contact with the object, and the object (also referred to as information regarding the shear force of the contact portion). For example, the shear displacement amount detection unit  301  performs a process related to detection of information regarding the shear displacement as the information regarding the shear force. In this case, the shear displacement amount detection unit  301  includes, for example, a sensor for detecting the shear displacement, such as a pressure distribution sensor or an image sensor, and a signal processing block that performs signal processing on an output signal of the sensor. As described in &lt;Specific Example of Method of Measuring Shear Displacement Amount&gt; in the first embodiment, the shear displacement amount detection unit  301  detects the shear displacement as a CoP change amount, a contact region movement amount, or the like. The shear displacement amount detection unit  301  supplies, to the shear displacement amount calculation unit  302 , the detected information (the CoP change amount, the contact region movement amount, or the like) as the information regarding the shear force of the contact portion (or the information regarding the shear displacement). 
     The shear displacement amount calculation unit  302  calculates the shear displacement amount. The shear displacement amount calculation unit  302  converts the information regarding the shear force of the contact portion (or the information regarding the shear displacement, for example, the CoP change amount, the contact region movement amount, or the like) supplied from the shear displacement amount detection unit  301  into the shear displacement amount, and supplies the shear displacement amount to the gripping force calculation unit  303 . 
     The gripping force calculation unit  303  calculates the gripping force (torque and force). The gripping force calculation unit  303  calculates a gripping force corresponding to the shear displacement amount supplied from the shear displacement amount calculation unit  302 . For example, the gripping force calculation unit  303  calculates such a gripping force that the shear displacement amount supplied from the shear displacement amount calculation unit  302  is made zero. That is, the gripping force calculation unit  303  calculates the gripping force on the basis of the information regarding the shear force of the contact portion (or the information regarding the shear displacement). The gripping force calculation unit  303  supplies the calculated gripping force to the actuator control unit  304 . 
     The actuator control unit  304  controls driving of the gripping device  102 . The actuator control unit  304  controls the gripping device  102  to drive the gripping device  102  so as to generate the gripping force supplied from the gripping force calculation unit  303  (for example, the object is supported by the gripping force). That is, the actuator control unit  304 , which is a drive control unit, controls driving of a support unit (for example, the gripping device  102 ) that supports the object, and causes the object to be supported with a supporting force controlled by a supporting force control unit (for example, the gripping force calculation unit  303 ). 
     Each processing unit (in the case of the example of  FIG. 27 , the shear displacement amount detection unit  301  to the actuator control unit  304 ) of the control device  101  can have any configuration. For example, each processing unit of the control device  101  may be configured by a logic circuit that implements the above-described processes. Furthermore, each processing unit of the control device  101  may include, for example, a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like, and execute a program using the CPU, the ROM, the RAM, and the like, thereby implementing the above-described processes. Needless to say, each processing unit of the control device  101  may have both of these configurations, and a part of the above-described processes may be implemented by the logic circuit and the other processes may be implemented by the execution of the program. The same applies to other drawings described below. 
     &lt;Procedure of Control Process&gt; 
     An example of a procedure of a control process executed by the control device  101  in this case will be described with reference to a flowchart of  FIG. 28 . When the control process is started, in step S 301 , the shear displacement amount detection unit  301  detects the information regarding the shear force (for example, the CoP change amount, the contact region movement amount, or the like). 
     In step S 302 , the shear displacement amount calculation unit  302  calculates the shear displacement amount on the basis of the information regarding the shear force of the contact portion (or the information regarding the shear displacement) detected in step S 301 . 
     In step S 303 , the gripping force calculation unit  303  calculates the gripping force (supporting force) on the basis of the shear displacement amount calculated in step S 302 . 
     In step S 304 , the actuator control unit  304  controls driving of an actuator of the gripping device  102  so as to support the object with the gripping force (supporting force) calculated in step S 303 . 
     When the process of step S 304  ends, the control process ends. 
     When each process is executed as described above, the control device  101  can control the gripping force (supporting force) of the gripping device  102  on the basis of the detected shear force (for example, the shear displacement) of the contact portion. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Control Device&gt; 
     In addition, a gripping force actually applied to the object may be measured, and the gripping force may be controlled on the basis of a measured value.  FIG. 29  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 29 , in this case, the control device  101  includes a gripping force measurement unit  311  in addition to the configuration of the example of  FIG. 27 . 
     The gripping force measurement unit  311  includes a torque sensor, a triaxial force sensor, or the like, and measures the gripping force actually applied to the object by the gripping device  102  (also referred to as an actual gripping force). The gripping force measurement unit  311  supplies the measured actual gripping force (torque and force) to the gripping force calculation unit  303 . 
     The gripping force calculation unit  303  calculates the gripping force to be applied to the gripping device  102  on the basis of the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)) supplied from the shear displacement amount calculation unit  302  and the actual gripping force supplied from the gripping force measurement unit  311 . That is, the gripping force calculation unit  303  corrects, by use of the actual gripping force, the gripping force calculated from the shear displacement amount. The gripping force calculation unit  303  supplies the calculated gripping force to the actuator control unit  304 . 
     As described above, by feeding back the measured gripping force, the control device  101  can perform the gripping force control with higher accuracy. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 30 . When the control process is started, respective processes of steps S 321  and S 322  are performed similarly to respective processes of steps S 301  and S 302  in  FIG. 28 . 
     In step S 323  ( FIG. 30 ), the gripping force measurement unit  311  measures the gripping force actually applied to the object. 
     In step S 324 , the gripping force calculation unit  303  calculates the gripping force to be output by the gripping device  102  on the basis of the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)) calculated in step S 322  and the gripping force measured in step S 323  (corrects the gripping force calculated on the basis of the shear displacement amount by use of the measured gripping force). 
     A process of step S 325  is performed similarly to the process of step S 304  ( FIG. 28 ). 
     In step S 326 , the control device  101  determines whether or not to end the control process. In a case where it is determined not to end the process, the process returns to step S 323 . That is, each process of steps S 323  to S 326  is repeatedly executed. 
     Then, in a case where it is determined in step S 326  that the control process is to be ended, the control process is ended. 
     By executing each process as described above, the control device  101  can control the gripping force (supporting force) of the gripping device  102  using the measured actual gripping force. Therefore, the control device  101  can perform more accurate gripping force control. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Control Device&gt; 
     In addition, the gripping force calculation unit  303  may calculate the gripping force on the basis of the shape or the like of the flexible deformation layer of the gripping device  102 .  FIG. 31  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 31 , in this case, the control device  101  includes a contact information holding unit  321  in addition to the configuration of the example of  FIG. 27 . 
     The contact information holding unit  321  includes any storage medium such as a flash memory, for example, and stores, in the storage medium, contact information, which is information regarding contact between the gripping device  102  and the object gripped by the gripping device  102 . 
     The contact information holding unit  321  supplies the held contact information to the gripping force calculation unit  303 . The gripping force calculation unit  303  calculates the gripping force on the basis of the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)) supplied from the shear displacement amount calculation unit  302  and the contact information supplied from the contact information holding unit  321 . The gripping force calculation unit  303  supplies the gripping force to the actuator control unit  304 . 
     The contact information includes, for example, information regarding the shape of the surface of the flexible deformation layer  212  of the gripping device  102  (that is, the contact portion in contact with the object). That is, the gripping force calculation unit  303 , which is the supporting force control unit, controls the gripping force (that is, the supporting force for supporting the object) on the basis of the information regarding the shape of the surface of the flexible deformation layer  212  and the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)). 
     For example, the contact information holding unit  321  may store, in the storage medium, the information regarding the shape of the surface of the flexible deformation layer  212  of the gripping device  102 , and the gripping force calculation unit  303  may control the gripping force on the basis of the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)) and the information regarding the shape of the surface of the flexible deformation layer  212  of the gripping device  102  held by the contact information holding unit  321 . 
     Note that the information regarding the shape may include, for example, information indicating the curvature of the surface of the flexible deformation layer  212  (information indicating the curvature of the surface of the contact portion). That is, the gripping force calculation unit  303  may control the gripping force on the basis of the information indicating the curvature of the surface of the flexible deformation layer  212  and the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)). 
     Furthermore, a position control unit (the gripping force calculation unit  303 ) that controls the position of the contact portion, which is in contact with the object, on the basis of the information indicating the curvature of the surface of the flexible deformation layer  212  may be further included. For example, the gripping force calculation unit  303  may further serve as the position control unit to select whether to bring the object into contact with a portion of the flexible deformation layer, which has a large curvature, and grip the object by the precision grip (fingertip grip), or bring the object into contact with a portion of the flexible deformation layer, which has a small curvature, and grip the object by the power grip, and control the gripping device  102  to grip the object by the selected method. 
     Furthermore, the information regarding the shape may include the information indicating the shape of the surface of the flexible deformation layer  212  (for example, whether the shape is a flat surface, a curved surface, or the like). That is, the gripping force calculation unit  303  may control the gripping force on the basis of the information indicating the shape of the surface of the flexible deformation layer  212  and the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)). 
     Furthermore, the contact information may include information regarding a curved surface of the object with which the gripping device  102  comes into contact. That is, the gripping force calculation unit  303  may control the gripping force on the basis of the information regarding the curved surface of the object with which the gripping device  102  comes into contact and the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)). 
     Needless to say, the contact information or the information regarding the shape may include information other than the above-described information. 
     As described above, by calculating the gripping force using the contact information in addition to the shear displacement amount (that is, the information regarding the shear force of the contact portion (or the information regarding the shear displacement)), the gripping force calculation unit  303  can calculate the minimum required gripping force with higher accuracy. 
     Note that the contact information may be recognized (detected) and held. In this case, the control device  101  is only required to further include a recognition unit that recognizes the contact information (or a detection unit that detects the contact information), and the contact information output from the recognition unit (or the detection unit) is only required to be held by the contact information holding unit  321 . 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 32 . When the control process is started, respective processes of steps S 341  and S 342  are performed similarly to respective processes of steps S 301  and S 302  in  FIG. 28 . 
     In step S 343  ( FIG. 32 ), the gripping force calculation unit  303  calculates the gripping force on the basis of the shear displacement amount calculated in step S 342  and the contact information (for example, the curvature of the flexible deformation layer) held by the contact information holding unit  321 . That is, the gripping force calculation unit  303 , which is the supporting force control unit, controls the supporting force (gripping force) for supporting the object on the basis of the information regarding the shape of the contact portion in contact with the object (contact information) and the information regarding the shear force of the contact portion (or the information regarding the shear displacement). 
     A process of step S 344  is performed similarly to the process of step S 304  ( FIG. 28 ). Then, the control process ends when the process of step S 344  ends. 
     By executing each process as described above, the control device  101  can control the gripping force (supporting force) of the gripping device  102  using the shear displacement amount and the contact information (for example, the curvature of the flexible deformation layer). Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Control Device&gt; 
     Note that the slip direction can be determined from a direction of the shear displacement. By controlling the gripping force according to the slip direction, the control device  101  can perform control to allow a slip only in a certain direction or, on the contrary, to prevent a slip in a certain direction. 
       FIG. 33  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 33 , in this case, the control device  101  includes a gripping force decision unit  331  in addition to the configuration of the example of  FIG. 27 . Furthermore, in this case, gripping force calculation units  303  calculate a gripping force for each direction (for example, for each of x, y, θ, and the like). That is, the control device  101  includes, for each direction (for example, for each of x, y, θ, and the like), the gripping force calculation unit  303  (gripping force calculation units  303 - 1  to  303 -N (N is any natural number)). 
     The shear displacement amount calculation unit  302  in this case calculates a shear displacement amount for each direction (for example, for each of x, y, θ, and the like), and supplies each of the calculated shear displacement amounts to one of the gripping force calculation units  303 , which corresponds to the direction of the shear displacement amount (one of the gripping force calculation units  303 - 1  to  303 -N). 
     Each of the gripping force calculation units  303 - 1  to  303 -N is the gripping force calculation unit  303  provided for each direction (for example, for each of x, y, θ, and the like), and calculates the gripping force for the corresponding direction (for example, x, y, θ, or the like) on the basis of the shear displacement amount in the corresponding direction (that is, a slip amount in the corresponding direction). That is, in this case, the gripping force calculation units  303  (the gripping force calculation units  303 - 1  to  303 -N) derive the gripping force for each direction on the basis of the shear displacement amount for each direction (that is, information regarding the shear force of the contact portion for each direction (or information regarding the shear displacement for each direction)). 
     For example, one of the gripping force calculation units  303 , which corresponds to the rotation direction θ, controls the supporting force on the basis of a rotational slip, which is a slip of the object relative to the contact portion in the rotation direction. This rotational slip is derived on the basis of the pressure distribution applied to the gripped object by the contact portion. That is, each of the gripping force calculation units  303 , which is the supporting force control unit, controls the supporting force on the basis of a detection result of the pressure distribution applied to the object by the contact portion. 
     The gripping force calculation units  303 - 1  to  303 -N supply the calculated gripping force (torque and force) for each direction to the gripping force decision unit  331 . 
     The gripping force decision unit  331  decides the gripping force to be output from the supplied gripping force for each direction (for example, for each of x, y, θ, and the like). The gripping force decision unit  331  supplies the decided gripping force to the actuator control unit  304 . That is, in this case, the gripping force calculation units  303  (the gripping force calculation units  303 - 1  to  303 -N) and the gripping force decision unit  331  derive the gripping force on the basis of the shear displacement amount for each direction (that is, the information regarding the shear force of the contact portion for each direction (or the information regarding the shear displacement for each direction)). 
     By controlling the gripping force according to the slip direction in this manner, the control device  101  can achieve more various support control such as allowing a slip only in a certain direction or, on the contrary, preventing a slip in a certain direction, for example. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 34 . When the control process is started, a process of step S 361  is performed similarly to the process of step S 301  in  FIG. 28 . 
     In step S 362  ( FIG. 32 ), the shear displacement amount calculation unit  302  calculates the shear displacement amount for each direction (for example, for each of x, y, θ, and the like) on the basis of the information detected in step S 361 . 
     In step S 363 , the gripping force calculation units  303  calculate the gripping force for each direction on the basis of the shear displacement amount for each direction calculated in step S 362 . 
     In step S 364 , the gripping force decision unit  331  decides the gripping force to be output from the gripping force for each direction calculated in step S 363 . 
     In step S 365 , the actuator control unit  304  controls driving of the actuator of the gripping device  102  so as to support the object with the gripping force (supporting force) decided in step S 364 . Then, the control process ends when the process of step S 365  ends. 
     By executing each process as described above, the control device  101  can control the gripping force according to the slip direction, and can achieve more various support control. 
     &lt;Control Device&gt; 
     In the calculation of the gripping force, a control parameter may be switched for each direction.  FIG. 35  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 35 , in this case, the control device  101  includes a control parameter storage unit  341  in addition to the configuration of the example of  FIG. 33 . 
     The control parameter storage unit  341  includes any storage medium (for example, a flash memory or the like), and stores, in the storage medium, a control parameter  342  for each direction (for example, for each of x, y, θ, and the like) (control parameters  342 - 1  to  342 -M (M is any natural number)), which is used for the calculation of the gripping force. The control parameter storage unit  341  supplies the stored control parameter  342  to the gripping force calculation unit  303  as necessary. 
     Note that the control parameter may be any information. For example, the control parameter may be a control gain or a control target of a proportional-integral-differential controller (PID). 
     Also in this case, as in the case of  FIG. 33 , the shear displacement amount calculation unit  302  calculates the shear displacement amount for each direction (for example, for each of x, y, θ, and the like), and the gripping force calculation unit  303  calculates the gripping force for each direction (for example, for each of x, y, θ, and the like). 
     However, the gripping force calculation unit  303  calculates the gripping force for each direction (for example, for each of x, y, θ, and the like) on the basis of the shear displacement amount for each direction supplied from the shear displacement amount calculation unit  302 , and the control parameter for each direction supplied from the control parameter storage unit  341 . 
     The gripping force decision unit  331  decides the gripping force to be output from the gripping force for each direction (for example, for each of x, y, θ, and the like) calculated by the gripping force calculation unit  303 . 
     In this manner, the gripping force calculation unit  303  can calculate the minimum required gripping force for each direction with higher accuracy. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 36 . When the control process is started, respective processes of steps S 381  and S 382  are performed similarly to respective processes of steps S 361  and S 362  in  FIG. 34 . 
     In step S 383  ( FIG. 36 ), the gripping force calculation unit  303  calculates the gripping force for each direction on the basis of the shear displacement amount for each direction calculated in step S 362  and the control parameter  342  for each direction stored in the control parameter storage unit  341 . 
     Respective processes of steps S 384  and S 385  are performed similarly to respective processes of steps S 364  and S 365  ( FIG. 34 ). Then, the control process ends when the process of step S 385  ends. 
     By executing each process as described above, the control device  101  can control the gripping force according to the slip direction with higher accuracy. 
     &lt;Control Device&gt; 
     The gripping force may be controlled according to an assignment of task input from the outside.  FIG. 37  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 37 , in this case, the control device  101  includes a task assignment unit  351  and a slip direction designation unit  352  in addition to the configuration of the example of  FIG. 33 . 
     The task assignment unit  351  is a processing unit that assigns a task to the gripping device  102 . For example, the task assignment unit  351  may include an input device that receives the assignment from the outside. The task assignment unit  351  supplies the assignment to the slip direction designation unit  352 . 
     The slip direction designation unit  352  decides a direction in which a slip is allowed (or a direction in which a slip is not allowed), a direction in which the gripping force is increased, and the like on the basis of the task assigned from the task assignment unit  351 . When deciding the control parameter such as a gain for each direction, which is used for the calculation of the gripping force, the slip direction designation unit  352  supplies the control parameter to one of the gripping force calculation units  303  (the gripping force calculation units  303 - 1  to  303 -N), which corresponds to the direction of the control parameter. In addition, when deciding the direction in which a slip is allowed (or the direction in which a slip is not allowed), the slip direction designation unit  352  supplies information indicating the direction (decision method control information) to the gripping force decision unit  331 . 
     The gripping force calculation units  303  calculate the gripping force for each direction (for example, for each of x, y, θ, and the like) on the basis of the shear displacement amount for each direction supplied from the shear displacement amount calculation unit  302  and the control parameter for each direction supplied from the slip direction designation unit  352 , and supply the gripping force to the gripping force decision unit  331 . 
     The gripping force decision unit  331  decides the gripping force to be output on the basis of the gripping force for each direction supplied from the gripping force calculation units  303  and the decision method control information supplied from the slip direction designation unit  352 . For example, the gripping force decision unit  331  decides the gripping force to be output according to an instruction such as “ignore a gripping force in the X direction” or “allow a slip in the Y direction”, which is supplied from the slip direction designation unit  352 . 
     In this manner, the gripping force calculation units  303  can calculate the gripping force according to the assignment of the task. As a result, the control device  101  can achieve more various support control. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 38 . When the control process is started, respective processes of steps S 401  and S 402  are performed similarly to respective processes of steps S 361  and S 362  in  FIG. 34 . 
     In step S 403  ( FIG. 38 ), the task assignment unit  351  receives the task assignment. In step S 404 , the slip direction designation unit  352  sets the slip direction designation such as the control parameter for each direction and the decision method control information described above on the basis of the task assignment. 
     In step S 405 , the gripping force calculation units  303  calculate the gripping force for each direction on the basis of the shear displacement amount for each direction calculated in step S 362  and the slip direction designation (the control parameter for each direction) set in step S 404 . 
     In step S 406 , the gripping force decision unit  331  decides the gripping force on the basis of the gripping force for each direction calculated in step S 405  and the slip direction designation (decision method control information) set in step S 404 . 
     A process of step S 407  is performed similarly to the process of step S 365  ( FIG. 34 ). Then, the control process ends when the process of step S 407  ends. 
     By executing each process as described above, the control device  101  can control the gripping force according to the task assignment. 
     &lt;Control Device&gt; 
     Even in a case where the gripping force control is performed according to the task assignment as described above, a result of the control is not necessarily as ideal. For example, a correct result of the control may not be obtained depending on an actual situation such as a control error or an obstacle. Therefore, the surroundings or a position, orientation, or the like (environment) of the gripped object may be further recognized, and the support control may be performed on the basis of a result of the recognition. 
       FIG. 39  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 39 , in this case, the control device  101  includes an environment recognition unit  361  in addition to the configuration of the example of  FIG. 37 . 
     The environment recognition unit  361  recognizes the surrounding or the orientation and position of the gripped object, and derives differences between results of the recognition and target values. The environment recognition unit  361  supplies information indicating the differences to the slip direction designation unit  352 . 
     The slip direction designation unit  352  sets the slip direction designation (control parameter for each direction, decision method control information, and the like) on the basis of the information indicating the differences and information regarding the task assignment. 
     According to such control, for example, when the orientation of the object is changed, the control device  101  may change the position and orientation of the object by operating an arm, but can also change the position and orientation of the object by slipping the object. As described above, the gripping force calculation units  303  can achieve more various support control with higher accuracy according to the actual situation. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 40 . When the control process is started, respective processes of steps S 421  to S 423  are executed similarly to respective processes of steps S 401  to S 403  in  FIG. 38 . 
     In step S 424  ( FIG. 40 ), the environment recognition unit  361  recognizes the environment. 
     In step S 425 , the slip direction designation unit  352  sets the slip direction designation such as the control parameter for each direction and the decision method control information described above on the basis of the task assignment and the recognition results of the environment. 
     Respective processes of steps S 426  to S 428  are executed similarly to respective processes of steps S 405  to S 407  in  FIG. 38 . Then, the control process ends when the process of step S 428  ends. 
     By executing each process as described above, the control device  101  can control the gripping force according to the task assignment and the environment. 
     &lt;Control Device&gt; 
     Method 2 (sticking ratio estimation by detection of the discontinuous point of the shear force distribution and the shear displacement distribution) described in the first embodiment can also be applied.  FIG. 41  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 41 , in this case, the control device  101  includes a shear displacement amount distribution detection unit  401 , a shear displacement amount distribution calculation unit  402 , a shear force distribution calculation unit  403 , a distribution information processing unit  404 , a sticking ratio calculation unit  405 , a target sticking ratio setting unit  406 , the gripping force calculation unit  303 , and the actuator control unit  304 . 
     The shear displacement amount distribution detection unit  401  performs a process related to detection of a distribution of the information regarding the shear displacement as the information regarding the shear force. Similarly to the shear displacement amount detection unit  301 , the shear displacement amount distribution detection unit  401  includes, for example, a sensor for detecting the information regarding the shear displacement, such as a pressure distribution sensor or an image sensor, and a signal processing block that performs signal processing on an output signal of the sensor. However, the shear displacement amount distribution detection unit  401  detects the information regarding the shear displacement (for example, the CoP change amount or the contact region movement amount) at all observation points and generates distribution information of the information regarding the shear displacement. The shear displacement amount distribution detection unit  401  supplies the distribution information of the information regarding the shear displacement to the shear displacement amount distribution calculation unit  402 . 
     The shear displacement amount distribution calculation unit  402  converts the distribution information of the information regarding the shear displacement (for example, the CoP change amount, the contact region movement amount, or the like for all observation points) supplied from the shear displacement amount distribution detection unit  401 , into distribution information of the shear displacement amount (for example, the shear displacement amount for all observation points), and supplies the distribution information to the shear force distribution calculation unit  403 . 
     The shear force distribution calculation unit  403  calculates distribution information of the shear force on the basis of the distribution information of the shear displacement amount supplied from the shear displacement amount distribution calculation unit  402 . For example, the shear force distribution calculation unit  403  converts the shear displacement amount into the shear force for all observation points. The shear force distribution calculation unit  403  supplies the distribution information of the calculated shear force to the distribution information processing unit  404 . 
     The distribution information processing unit  404  detects the discontinuous point from the distribution information of the shear force (for example, the graph of  FIG. 9 ) supplied from the shear force distribution calculation unit  403 . The distribution information processing unit  404  supplies information indicating the discontinuous point to the sticking ratio calculation unit  405 . 
     The sticking ratio calculation unit  405  specifies the sticking region and the slip region on the basis of the information indicating the discontinuous point supplied from the distribution information processing unit  404 , and calculates the sticking ratio from these specified regions. The sticking ratio calculation unit  405  supplies the calculated sticking ratio to the gripping force calculation unit  303 . 
     The target sticking ratio setting unit  406  sets a target value of the sticking ratio (also referred to as a target sticking ratio) and supplies the target value to the gripping force calculation unit  303 . 
     The gripping force calculation unit  303  calculates the gripping force on the basis of the sticking ratio calculated by the sticking ratio calculation unit  405  and the target sticking ratio set by the target sticking ratio setting unit  406 , and supplies the gripping force to the actuator control unit  304 . That is, the gripping force calculation unit  303 , which is the supporting force control unit, controls the supporting force on the basis of the distribution of the shear force derived by use of the distribution of the shear displacement amount calculated from the distribution of the detected information regarding the shear displacement. 
     The actuator control unit  304  controls the gripping device  102  to drive the gripping device  102  so as to generate the gripping force supplied from the gripping force calculation unit  303  (for example, the object is supported by the gripping force). 
     In this manner, the control device  101  can perform the support control by applying Method 2. 
     Note that the distribution information processing unit  404  may detect the discontinuous point using the distribution information of the shear displacement amount. In this case, the shear force distribution calculation unit  403  may be omitted. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 42 . When the control process is started, in step S 441 , the shear displacement amount distribution detection unit  401  detects the information regarding the distribution of the shear displacement amount (for example, distribution information of the CoP change amount, the contact region movement amount, or the like) as the information regarding the shear force. 
     In step S 442 , the shear displacement amount distribution calculation unit  402  calculates the distribution information of the shear displacement amount on the basis of the information detected in step S 401 . 
     In step S 443 , the shear force distribution calculation unit  403  calculates the distribution information of the shear force using the distribution information of the shear displacement amount calculated in step S 402 . 
     In step S 444 , the distribution information processing unit  404  detects the discontinuous point on the basis of the distribution information of the shear force calculated in step S 443 . 
     In step S 445 , the sticking ratio calculation unit  405  specifies the sticking region and the slip region on the basis of the discontinuous point detected in step S 444 , and calculates the sticking ratio on the basis of each of the specified regions. 
     In step S 446 , the target sticking ratio setting unit  406  sets the target sticking ratio, which is the target value of the sticking ratio. 
     In step S 447 , the gripping force calculation unit  303  calculates the gripping force (supporting force) on the basis of the sticking ratio calculated in step S 445  and the target sticking ratio set in step S 446 . 
     In step S 448 , the actuator control unit  304  controls driving of the actuator of the gripping device  102  so as to support the object with the gripping force (supporting force) calculated in step S 447 . 
     When the process of step S 447  ends, the control process ends. 
     By executing each process as described above, the control device  101  can control the gripping force (supporting force) of the gripping device  102  by applying Method 2. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Control Device&gt; 
     Method 3 (sticking ratio estimation using time-series information of the shear force distribution and the shear displacement distribution) described in the first embodiment can also be applied.  FIG. 43  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 43 , in this case, the control device  101  includes a distribution information storage unit  411  and a distribution time-series information processing unit  412  instead of the distribution information processing unit  404  in the example of  FIG. 41 . 
     The distribution information storage unit  411  includes a storage medium such as a flash memory, for example, and stores the distribution information of the shear force calculated by the shear force distribution calculation unit  403 . The distribution information storage unit  411  generates distribution time-series information, which is information indicating a time-series change in the distribution information of the shear force, on the basis of the stored distribution information of the shear force at each time, and supplies the distribution time-series information to the distribution time-series information processing unit  412 . 
     The distribution time-series information processing unit  412  acquires the latest distribution information of the shear force from the shear force distribution calculation unit  403 . In addition, the distribution time-series information processing unit  412  acquires past distribution time-series information supplied from the distribution information storage unit  411 . The distribution time-series information processing unit  412  specifies the slip region and the sticking region on the basis of these pieces of distribution time-series information of the shear force. 
     The sticking ratio calculation unit  405  calculates the sticking ratio on the basis of the slip region and the sticking region specified by the distribution time-series information processing unit  412 . 
     That is, in this case, the gripping force calculation unit  303 , which is the supporting force control unit, controls the supporting force on the basis of the time-series change in the distribution of the shear force, which is generated by use of the distribution information storage unit  411 . 
     As described above, if the slip region and the like are specified on the basis of the time-series information of the distribution information of the shear force so that the sticking ratio is derived, the support control can be performed by application of Method 3. 
     Note that the distribution time-series information processing unit  412  may detect the discontinuous point using the distribution information of the shear displacement amount. In this case, the shear force distribution calculation unit  403  may be omitted. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 44 . When the control process is started, respective processes of steps S 461  to S 463  are executed similarly to respective processes of steps S 441  to S 443 . 
     In step S 464 , the distribution information storage unit  411  stores the distribution information of the shear force calculated by the process in step S 463 . 
     In step S 465 , the distribution time-series information processing unit  412  processes the distribution time-series information using the distribution information of the shear force calculated in step S 463  and the distribution information stored in the distribution information storage unit  411 . That is, the slip region and the sticking region are specified. 
     Respective processes of steps S 466  to S 469  are executed similarly to respective processes of steps S 445  to S 448 . Then, the control process ends when the process of step S 469  ends. 
     By executing each process as described above, the control device  101  can control the gripping force (supporting force) of the gripping device  102  by applying Method 3. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Control Device&gt; 
     Method 1 and Method 3 described in the first embodiment can also be applied in combination.  FIG. 45  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 45 , in this case, the control device  101  includes the shear displacement amount distribution detection unit  401  to the target sticking ratio setting unit  406 , gripping force calculation units  303 - 1  and  303 - 2 , the actuator control unit  304 , the contact information holding unit  321 , and calculation units  421  and  422 . 
     When setting the target sticking ratio, the target sticking ratio setting unit  406  feeds forward the target sticking ratio to the gripping force calculation unit  303 - 1 . The gripping force calculation unit  303 - 1  calculates the gripping force on the basis of the fed-forward target sticking ratio and the contact information held by the contact information holding unit  321 . The gripping force calculation unit  303 - 1  supplies the calculated gripping force to the actuator control unit  304  via the calculation unit  422 . If the feedforward is performed by use of the target sticking ratio in this manner, the support control can be performed at a higher response speed. 
     The shear displacement amount distribution detection unit  401  to the sticking ratio calculation unit  405  perform processes as in the case of  FIG. 41 . The sticking ratio calculation unit  405  feeds back the calculated sticking ratio to the calculation unit  421 . In addition, the target sticking ratio setting unit  406  supplies the set target sticking ratio to the calculation unit  421 . 
     The calculation unit  421  subtracts the sticking ratio calculated by the sticking ratio calculation unit  405  from the target sticking ratio. The calculation unit  421  supplies a result of the calculation to the gripping force calculation unit  303 - 2 . 
     The gripping force calculation unit  303 - 2  supplies the sticking ratio difference supplied from the calculation unit  421  to the gripping force calculation unit  303 - 2 . The gripping force calculation unit  303 - 2  calculates the gripping force on the basis of the difference and supplies the gripping force to the calculation unit  422 . 
     The calculation unit  422  adds the gripping force supplied from the gripping force calculation unit  303 - 2  to the gripping force supplied from the gripping force calculation unit  303 - 1 , and supplies a result of the addition to the actuator control unit  304 . That is, the gripping force calculated by the gripping force calculation unit  303 - 1  is corrected by the gripping force calculated by the gripping force calculation unit  303 - 2 . The actuator control unit  304  controls the actuator using a result of the correction. As described above, by deriving and feeding back the sticking ratio on the basis of the detected information, the control device  101  can correct the gripping force calculated by the feedforward. Therefore, the control device  101  can perform more robust control. That is, the control device  101  can perform more robust and highly responsive control. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 46 . When the control process is started, in step S 441 , the shear displacement amount distribution detection unit  401  detects the information regarding the distribution of the shear displacement amount (for example, the distribution information of the CoP change amount, the contact region movement amount, or the like). 
     When the control process is started, in step S 481 , the target sticking ratio setting unit  406  sets the target sticking ratio. 
     In step S 482 , the gripping force calculation unit  303 - 1  calculates the gripping force on the basis of the target sticking ratio set in step S 481  and the contact information. 
     In step S 483 , the actuator control unit  304  controls the actuator using the gripping force calculated in step S 482 . 
     Respective processes of steps S 484  to S 488  are executed similarly to respective processes of steps S 441  to S 445  in  FIG. 42 . 
     In step S 489 , the calculation unit  421 , the gripping force calculation unit  303 - 2 , and the calculation unit  422  correct the gripping force on the basis of the sticking ratio calculated in step S 488  and the target sticking ratio generated in step S 481 . More specifically, the gripping force calculation unit  303 - 2  calculates the gripping force corresponding to the difference between the target sticking ratio and the calculated sticking ratio, and the calculation unit  422  adds the calculated gripping force to the gripping force calculated by the gripping force calculation unit  303 - 1  to correct the gripping force. 
     When the process of step S 490  ends, the control process ends. 
     By performing the control process in this manner, the control device  101  can control the gripping force (supporting force) of the gripping device  102  by applying Method 1 and Method 2. Therefore, the control device  101  can perform more robust and highly responsive control. 
     &lt;Case where Friction Coefficient can be Measured by Operation in Advance&gt; 
     &lt;Control Device&gt; 
     For example, in order to measure the friction coefficient of the object before the object is gripped, an operation of slipping an object  431  as illustrated in  FIG. 47  is performed, so that the friction coefficient can be estimated from the relationship between the shear force F X  and the gripping force Fu. The shear force may be estimated from the shear displacement obtained from a tactile sensor, or estimated by use of a three-axis sensor or the like separately attached to the fingertip. As for the gripping force, there are a method of estimating the gripping force from information obtained by the tactile sensor, a method of estimating the gripping force by use of a force sensor such as the three-axis sensor, a method of estimating the gripping force from a current of a motor, and the like. 
       FIG. 48  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 48 , in this case, the control device  101  includes the shear displacement amount detection unit  301 , the shear displacement amount calculation unit  302 , a friction coefficient measurement unit  441 , the contact information holding unit  321 , the sticking ratio calculation unit  405 , the target sticking ratio setting unit  406 , the gripping force calculation unit  303 , and the actuator control unit  304 . 
     The friction coefficient measurement unit  441  measures the friction coefficient. In addition, the friction coefficient measurement unit  441  may measure the gripping force F N  and calculate the friction coefficient using the gripping force F N . In this case, for example, the friction coefficient measurement unit  441  measures the gripping force F N  and derives the friction coefficient using the gripping force F N  and the force F X  in the shear direction. The friction coefficient measurement unit  441  supplies the friction coefficient to the sticking ratio calculation unit  405 . 
     The sticking ratio calculation unit  405  calculates the sticking ratio on the basis of the shear displacement amount supplied from the shear displacement amount calculation unit  302 , the friction coefficient supplied from the friction coefficient measurement unit  441 , and the contact information acquired from the contact information holding unit  321 . The sticking ratio calculation unit  405  supplies the calculated sticking ratio to the gripping force calculation unit  303 . 
     The gripping force calculation unit  303  calculates the gripping force using the target sticking ratio set by the target sticking ratio setting unit  406  and the sticking ratio supplied from the sticking ratio calculation unit  405 . That is, the gripping force calculation unit  303 , which is the supporting force control unit, controls the supporting force on the basis of the friction coefficient between the object and the contact portion. 
     As described above, by performing the support control using the measured friction coefficient, the control device  101  can perform more accurate gripping force control. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 49 . When the control process is started, in step S 501 , the shear displacement amount detection unit  301  detects information regarding the shear displacement amount. 
     In step S 502 , the shear displacement amount calculation unit  302  calculates the shear displacement amount using the information regarding the shear displacement amount detected in step S 501 . 
     In step S 503 , the friction coefficient measurement unit  441  measures the friction coefficient. In step S 504 , the sticking ratio calculation unit  405  calculates the sticking ratio on the basis of the shear displacement amount, the contact information, and the friction coefficient. 
     In step S 505 , the gripping force calculation unit  303  calculates the gripping force on the basis of the calculated sticking ratio and the target sticking ratio. In step S 506 , the actuator control unit  304  controls the actuator using the gripping force calculated in step S 505 . 
     When the process of step S 506  ends, the control process ends. 
     By executing each process in this manner, the control device  101  can perform the support control using the friction coefficient. 
     Note that, also in this case, various variations described in &lt;Case where Friction Coefficient Is Not Known in Advance&gt; can be applied. 
     &lt;Case where Friction Coefficient is Known in Advance (Predictable)&gt; 
     &lt;Control Device&gt; 
     In a case where the friction coefficient is known in advance or predictable, the sticking ratio can be calculated directly from the shear displacement.  FIG. 50  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 50 , in this case, in the control device  101 , the friction coefficient measurement unit  441  is omitted from the configuration of the example of  FIG. 48 . 
     In this case, the friction coefficient can be included in the contact information held by the contact information holding unit  321 . Furthermore, the contact information may further include, for example, the information indicating the shape of the flexible deformation layer, the information indicating the curvature of the surface of the flexible deformation layer  212 , a sticking ratio model, elasticity, the information regarding the curved surface of the object with which the gripping device  102  comes into contact, or the like. 
     Furthermore, also in this case, the information regarding the contact curved surface may be held in advance as the contact information by the contact information holding unit  321 , or a result of recognition on the spot may be used. In the case of recognition, the recognition unit is required. The target sticking ratio may be obtained from task contents or a recognition result of the surrounding environment. These settings can also be changed depending on the slip direction. 
     Note that, also in this case, various variations described in &lt;Case where Friction Coefficient Is Not Known in Advance&gt; and &lt;Case where Friction Coefficient Can Be Measured by Operation in Advance&gt; can be applied. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 51 . When the control process is started, respective processes of steps S 521  and S 522  are performed similarly to respective processes of steps  3501  and  3502  in  FIG. 49 . 
     In step S 523 , the sticking ratio calculation unit  405  calculates the sticking ratio on the basis of the shear displacement amount calculated in step S 522  and the contact information stored in the contact information holding unit  321 . 
     Respective processes of steps S 524  and  3525  are performed similarly to respective processes of steps  3505  and S 506  in  FIG. 49 . When the process of step S 525  ends, the control process ends. 
     By executing each process in this manner, the control device  101  can perform the support control also in the case where the friction coefficient is known in advance. 
     &lt;Control Device&gt; 
     In addition, the sticking ratio can be derived for each direction of the shear displacement.  FIG. 52  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 52 , in this case, the control device  101  basically has a configuration similar to that of the example of  FIG. 50 . However, in this case, the control device  101  includes sticking ratio calculation units  405 - 1  to  405 -N, each of which corresponds to a direction (for example, x, y, θ, or the like), and the gripping force calculation units  303 - 1  to  303 -N, each of which corresponds to a direction (for example, x, y, θ, or the like). 
     The sticking ratio calculation units  405 - 1  to  405 -N calculate the sticking ratio for each direction (for example, for each of x, y, θ, and the like). The gripping force calculation units  303 - 1  to  303 -N calculate the gripping force for each direction (for example, each of x, y, θ, and the like). 
     In addition, the shear displacement amount calculation unit  302  calculates the shear displacement amount for each direction (for example, each of x, y, θ, and the like) and supplies the shear displacement amount for each direction to one of the sticking ratio calculation units  405 , which corresponds to the direction of the shear displacement amount. Furthermore, the contact information holding unit  321  holds the contact information for each direction (for example, each of x, y, θ, and the like), and appropriately supplies the contact information for each direction to one of the sticking ratio calculation units  405 , which corresponds to the same direction as the direction of the contact information. Moreover, the target sticking ratio setting unit  406  sets the target sticking ratio for each direction (for example, each of x, y, θ, and the like), and supplies the target sticking ratio for each direction to one of the gripping force calculation units  303 , which corresponds to the direction of the target sticking ratio. 
     In this manner, the control device  101  can control the gripping force according to the slip direction. Therefore, the control device  101  can achieve more various support control. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 53 . When the control process is started, a process of step  3541  is performed similarly to the process of step  3521  in  FIG. 51 . 
     In step S 542  ( FIG. 53 ), the shear displacement amount calculation unit  302  calculates the shear displacement amount for each direction (for example, for each of x, y, θ, and the like) on the basis of the information detected in step S 541 . 
     In step  3543 , the sticking ratio calculation units  405 - 1  to  405 -N calculate the gripping force for each direction on the basis of the shear displacement amount for each direction calculated in step S 542  and the contact information for each direction held by the contact information holding unit  321 . 
     In step S 544 , the gripping force calculation units  303 - 1  to  303 -N calculate the gripping force for each direction on the basis of the shear displacement amount for each direction calculated in step  3542  and the contact information for each direction held by the contact information holding unit  321 . 
     In step S 544 , the actuator control unit  304  calculates the gripping force for each direction from the gripping force for each direction calculated in step S 543 . 
     In step S 545 , the actuator control unit  304  controls driving of the actuator of the gripping device  102  so as to support the object with the gripping force (supporting force) decided in step S 544 . Then, the control process ends when the process of step S 545  ends. 
     By executing each process as described above, the control device  101  can control the gripping force according to the slip direction, and can achieve more various support control. 
     &lt;Case of Combining Gripping Force Control with Position Control&gt; 
     There is a case where an appropriate gripping force cannot be decided only by detection of the initial slip. For example, in a case illustrated in  FIG. 54 , the finger portion  201 B needs to not only suppress the slip but also compensate gravity of an object  461 , but the mass and the center of gravity position of the object  461  are often unknown. Therefore, a method of compensating the gravity by controlling the position of the finger portion  201  is conceivable. Furthermore, in a case where a tool or the like is used, the positional rigidity cannot be increased only by the force control, and thus it is also conceivable to achieve both the force control and the position control. 
       FIG. 55  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 55 , in this case, the control device  101  includes an angle/position detection unit  471 , a target position indication unit  472 , a position control unit  473 , and an output decision unit  474  in addition to the configuration of the example of  FIG. 27 . 
     The angle/position detection unit  471  includes any sensor, and detects the position, the angle, or both the position and the angle of a part of the gripping device  102 , such as the finger portion  201 , for example, or the whole of the gripping device  102 . The angle/position detection unit  471  supplies the detected information to the position control unit  473 . 
     The target position indication unit  472  indicates a target position of a control target (for example, the finger portion  201  or the like) to the position control unit  473 . 
     The position control unit  473  generates a torque and force so as to bring the position and angle of the control target close to target values on the basis of the target position supplied from the target position indication unit  472  and the detected information regarding the position, the angle, or both the position and the angle of a part or the whole of the gripping device  102  supplied from the angle/position detection unit  471 , and supplies the torque and force to the output decision unit  474 . 
     In addition, the gripping force calculation unit  303  supplies the gripping force (torque and force) calculated from the shear displacement amount to the output decision unit  474 . 
     The output decision unit  474  adds the torque and force supplied from the position control unit  473  and the gripping force (torque and force) supplied from the gripping force calculation unit  303  together, and supplies a result of the addition to the actuator control unit  304 . 
     In this manner, both the gripping force control and the position control can be achieved. 
     &lt;Procedure of Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 56 . When the control process is started, in step S 561 , the shear displacement amount detection unit  301  detects the information regarding the shear displacement amount (for example, the CoP change amount, the contact region movement amount, or the like). 
     In step S 562 , the shear displacement amount calculation unit  302  calculates the shear displacement amount on the basis of the information detected in step S 561 . 
     In step  3563 , the gripping force calculation unit  303  calculates the gripping force (supporting force) on the basis of the shear displacement amount calculated in step S 562 . 
     In step S 564 , the angle/position detection unit  471  detects the position and orientation (angle) of (a part or the whole of) the gripping device  102 . 
     In step S 565 , the position control unit  473  calculates the torque and force required for setting the position and orientation detected in step  3564  to the position and orientation indicated by the target position indication unit  472 . 
     In step S 566 , the output decision unit  474  adds the gripping force calculated in step  3563  and the torque and force derived in step  3565 . In step  3567 , the actuator control unit  304  controls the actuator on the basis of the torque and force added together in step S 566 . 
     When the process of step S 567  ends, the control process ends. 
     By performing the control as described above, the control device  101  can achieve both the gripping force control and the position control. 
     &lt;Case of Including Plurality of Fingers&gt; 
     &lt;Control Device&gt; 
     In a case where the gripping device  102  includes a plurality of finger portions  201  and orientations and positions thereof can be freely changed, the slip direction and the like are only required to be estimated by use of orientation information of the fingers. 
       FIG. 57  is a block diagram illustrating a main configuration example of the control device  101  in this case. As illustrated in  FIG. 57 , in this case, the control device  101  includes finger units  481 - 1  to  481 -L (L is any natural number), an orientation information providing unit  482 , a slip direction calculation unit  483 , and a gripping force calculation unit  484 . 
     The finger units  481 - 1  to  481 -L illustrate configurations provided in the finger portions  201 . Hereinafter, the finger units  481 - 1  to  481 -L will be referred to as a finger unit  481  in a case where it is not necessary to distinguish the finger units  481 - 1  to  481 -L from each other for description. 
     Each of the finger units  481  includes the shear displacement amount detection unit  301 , the shear displacement amount calculation unit  302 , and the gripping force calculation unit  303 . That is, each of the finger units  481  outputs a value calculated by the gripping force calculation unit  303  and supplies the value to the slip direction calculation unit  483 . 
     The orientation information providing unit  482  detects information regarding the position and orientation of the gripping device  102  (or the finger portion  201  or the like thereof), and supplies the information to the slip direction calculation unit  483  and the gripping force calculation unit  484 . 
     The slip direction calculation unit  483  obtains the slip direction on the basis of the torque and force supplied from each of the finger units  481  and the information regarding the position and orientation of the gripping device  102  supplied from the orientation information providing unit  482 . The slip direction calculation unit  483  supplies information indicating the obtained slip direction to the gripping force calculation unit  484 . 
     The gripping force calculation unit  484  calculates the gripping force on the basis of the information indicating the slip direction supplied from the slip direction calculation unit  483  and the information regarding the position and orientation of the gripping device  102  supplied from the orientation information providing unit  482 , and supplies the gripping force to the actuator control unit  304 . 
     In this manner, each of the finger portions  201  of the gripping device  102  can support the object with a more appropriate supporting force. 
     &lt;Control Process&gt; 
     An example of the procedure of the control process in this case will be described with reference to a flowchart of  FIG. 58 . When the control process is started, in step S 581 , the shear displacement amount detection unit  301  detects the information regarding the shear displacement amount for each finger. 
     In step S 582 , the shear displacement amount calculation unit  302  calculates the shear displacement amount for each finger on the basis of the information regarding the shear displacement amount detected in step S 581 . 
     In step S 583 , the gripping force calculation unit  303  calculates the gripping force for each finger on the basis of the shear displacement amount calculated in step S 582 . 
     In step S 584 , the orientation information providing unit  482  derives the orientation of each finger. 
     In step S 585 , the slip direction calculation unit  483  comprehensively calculates the slip direction on the basis of the gripping force for each finger and the orientation of each finger. 
     In step S 586 , the gripping force calculation unit  484  corrects the gripping force of each finger on the basis of the slip direction. 
     In step S 587 , the actuator control unit  304  controls the actuator of the gripping device  102 . 
     When the process of step S 587  ends, the control process ends. 
     By executing each process in this manner, the control device  101  can control the orientation of each finger according to the surrounding situation. Therefore, the control device  101  can perform more accurate gripping force control. Therefore, the control device  101  can cause the gripping device  102  to support the object with a more appropriate supporting force. 
     &lt;Summary&gt; 
     If the control is performed as described above, even an unknown object (the mass, the friction coefficient, the center of gravity position, and the like are unknown) can be gripped with the minimum required force, so that the unknown object can be gripped without being slipped off and crushed. 
     The initial slip can be detected in any direction such as the translation direction or the rotation direction, and the control can be performed in various orientations and directions. 
     In addition, if the contact surface is formed in a curved surface, the initial slip detection accuracy can be improved, and as a result, the gripping accuracy can be improved. 
     Furthermore, the contact surface is formed in a curved surface, so that the initial slip detection accuracy can be improved. Therefore, a change due to an external force can also be detected with high accuracy, and a stable operation can be performed even in various unknown environments. 
     With the configuration in which the flexible deformation layer is laminated on the sensor, the flexible deformation layer and the sensor can be separated. When only the flexible deformation layer is damaged, it is possible to replace the flexible deformation layer without changing the sensor. 
     Using a plurality of curvatures makes it possible to selectively use the contact portion according to the accuracy required for each application, and to achieve appropriate control according to the situation or the task. 
     4. Appendix 
     &lt;Support&gt; 
     In the above description, control in a case where a hand-shaped device holds the object, which is an example of support, has been described. However, the present technology is not limited to this example, and can also be applied to other control. That is, in the present specification, “support” indicates that the device comes into contact with the object and acts on the object. “Gripping” the object by the gripping device  102  of the gripping system  100  described above is an example of “support” by such a device. Therefore, for example, actions of a foot-type device such as standing on the ground, walking, kicking an object, and going up or down stairs or the like are also included in “support”. Therefore, the present technology can also be applied to control of such operations. Needless to say, the shape of the device is not limited to a “hand” or a “foot”, and may be any shape. 
     &lt;Computer&gt; 
     The above-described series of processes can be executed by hardware or software. In a case where the series of processes are executed by software, a program constituting the software is installed in a computer. Here, the computer includes a computer incorporated in dedicated hardware, a general-purpose personal computer, for example, capable of executing various functions by installing various programs, and the like. 
       FIG. 59  is a block diagram illustrating a configuration example of hardware of the computer that executes the above-described series of processes by the program. 
     In a computer  900  illustrated in  FIG. 59 , a central processing unit (CPU)  901 , a read only memory (ROM)  902 , and a random access memory (RAM)  903  are connected to each other via a bus  904 . 
     An input/output interface  910  is also connected to the bus  904 . An input unit  911 , an output unit  912 , a storage unit  913 , a communication unit  914 , and a drive  915  are connected to the input/output interface  910 . 
     The input unit  911  includes, for example, a keyboard, a mouse, a microphone, a touch panel, an input terminal, and the like. The output unit  912  includes, for example, a display, a speaker, an output terminal, and the like. The storage unit  913  includes, for example, a hard disk, a RAM disk, a nonvolatile memory, and the like. The communication unit  914  includes, for example, a network interface and the like. The drive  915  drives a removable medium  921  such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory. 
     In the computer configured as described above, for example, the CPU  901  loads a program stored in the storage unit  913  into the RAM  903  via the input/output interface  910  and the bus  904 , and executes the program, thereby performing the above-described series of processes. The RAM  903  also appropriately stores data and the like necessary for the CPU  901  to execute various processes. 
     The program executed by the computer can be applied by being recorded in the removable medium  921  as a package medium or the like, for example. In this case, the program can be installed in the storage unit  913  via the input/output interface  910  by the removable medium  921  being attached to the drive  915 . 
     Furthermore, the program can also be provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting. In this case, the program can be received by the communication unit  914  and installed in the storage unit  913 . 
     In addition, the program can be installed in the ROM  902  or the storage unit  913  in advance. 
     &lt;Configuration to which Present Technology is Applied&gt; 
     The present technology can be applied to any configuration. For example, the present technology can be implemented as a partial configuration of a device, such as a processor as a system large scale integration (LSI) or the like, a module using a plurality of processors or the like, a unit using a plurality of modules or the like, or a set in which other functions are further added to the unit. 
     Furthermore, for example, the present technology can also be applied to a network system configured by a plurality of devices. For example, the present technology may be implemented as cloud computing in which a function is shared and processed in cooperation by a plurality of devices via a network. For example, the present technology may be implemented in a cloud service that provides a service to any terminal such as a computer, a portable information processing terminal, or an Internet of Things (IoT) device. 
     Note that, in the present specification, a system means a set of a plurality of components (devices, modules (parts), and the like), and it does not matter whether or not all the components are in the same housing. Therefore, a plurality of devices housed in separate housings and connected via a network, and one device in which a plurality of modules is housed in one housing are both systems. 
     &lt;Field and Use to which Present Technology is Applicable&gt; 
     A system, a device, a processing unit, and the like to which the present technology is applied can be used in any fields such as traffic, medical care, crime prevention, agriculture, livestock industry, mining, beauty, factory, home appliance, weather, and natural monitoring, for example. In addition, a use thereof is also freely set. 
     &lt;Others&gt; 
     Embodiments of the present technology are not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present technology. 
     For example, a configuration described as one device (or processing unit) may be divided and configured as a plurality of devices (or processing units). On the contrary, configurations described above as a plurality of devices (or processing units) may be collectively configured as one device (or processing unit). Furthermore, needless to say, a configuration other than the above-described configuration may be added to the configuration of each device (or each processing unit). Moreover, a part of the configuration of a certain device (or processing unit) may be included in the configuration of another device (or another processing unit) as long as the configuration and operation of the entire system are substantially the same. 
     Furthermore, for example, the above-described program may be executed in any device. In this case, the device is only required to have necessary functions (functional blocks or the like) so that necessary information can be obtained. 
     Furthermore, for example, each step of one flowchart may be executed by one device, or may be shared and executed by a plurality of devices. Furthermore, in a case where a plurality of processes is included in one step, the plurality of processes may be executed by one device, or may be shared and executed by a plurality of devices. In other words, the plurality of processes included in one step can also be executed as a plurality of steps of processes. On the contrary, processes described as a plurality of steps can also be collectively executed as one step. 
     Furthermore, for example, in the program executed by the computer, processes of steps describing the program may be executed in time series in the order described in the present specification, executed in parallel, or executed individually at a required timing such as when a call is made. That is, as long as there is no contradiction, the process of each step may be executed in an order different from the above-described order. Moreover, the processes of the steps describing the program may be executed in parallel with a process of another program, or may be executed in combination with a process of another program. 
     Furthermore, for example, a plurality of techniques related to the present technology can be implemented independently as a single body as long as there is no contradiction. Needless to say, any plurality of techniques related to the present technology can be implemented in combination. For example, a part or the whole of the present technology described in any of the embodiments may be implemented in combination with a part or the whole of the present technology described in another embodiment. Furthermore, any part or the whole of the above-described present technology can also be implemented in combination with another technology not described above. 
     Note that the present technology may have the following configurations. 
     (1) A support device including 
     a detection unit that detects information regarding a shear force of a portion of the surface of the elastic body, the portion being in contact with the object. 
     (2) The support device according to (1), in which 
     the surface of the elastic body includes a flat surface and a curved surface. 
     (3) The support device according to (1) or (2), in which 
     the surface of the elastic body includes a surface having an unevenness and a curved surface. 
     (4) The support device according to any of (1) to (3), in which 
     the surface of the elastic body has a curvature corresponding to a direction. 
     (5) The support device according to any of (1) to (4), in which 
     a portion of the surface of the elastic body that may come into contact with the object has a plurality of curvatures different from each other. 
     (6) The support device according to any of (1) to (5), in which 
     the elastic body has a non-uniform hardness. 
     (7) The support device according to (6), in which 
     the elastic body has a plurality of local portions each having a higher hardness than a hardness of a portion surrounding the local portions. 
     (8) The support device according to any of (1) to (7), in which 
     the detection unit is arranged in a curved surface shape. 
     (9) The support device according to any of (1) to (8), further including 
     a plurality of the elastic bodies each having a curved surface. 
     (10) The support device according to (9), in which 
     the plurality of elastic bodies is formed at any positions. 
     (11) The support device according to (9) or (10), in which 
     the plurality of elastic bodies is formed at positions based on a predetermined regularity. 
     (12) The support device according to any of (9) to (11), in which 
     the plurality of elastic bodies has hardnesses different from each other. 
     (13) The support device according to any of (9) to (12), in which 
     the plurality of elastic bodies has heights different from each other. 
     (14) The support device according to any of (1) to (13), in which 
     the surface of the elastic body includes a flat surface portion and a plurality of curved surface portions protruding from the flat surface portion. 
     (15) The support device according to any of (1) to (14), in which 
     the surface of the elastic body includes a first curved surface portion having a first curvature, and a plurality of second curved surface portions each having a second curvature larger than the first curvature, the plurality of second curved surface portions protruding from the first curved surface portion. 
     (16) The support device according to any of (1) to (15), further including: 
     as the elastic body,
         a plurality of first elastic bodies each having a surface with a first curvature; and   a second elastic body having a surface with a second curvature, the second elastic body being superposed on the plurality of first elastic bodies.       

     (17) The support device according to (16), in which 
     each of the first elastic bodies has a hardness different from a hardness of the second elastic body. 
     (18) The support device according to (16) or (17), in which 
     the second elastic body has a surface with the first curvature in a direction opposite to a direction of the surface of each of the first elastic bodies, the surface of each of the first elastic bodies having the first curvature. 
     (19) The support device according to any of (1) to (18), in which 
     the detection unit detects the information regarding the shear force via the elastic body. 
     (20) The support device according to any of (1) to (19), in which 
     the elastic body and the detection unit are formed on each of a plurality of finger portions that grips the object. 
     REFERENCE SIGNS LIST 
     
         
           100  Gripping system 
           101  Control device 
           102  Gripping device 
           201  Finger portion 
           211  Sensor 
           212  Flexible deformation layer 
           231  Object 
           301  Shear displacement amount detection unit 
           302  Shear displacement amount calculation unit 
           303  Gripping force calculation unit 
           304  Actuator control unit 
           311  Gripping force measurement unit 
           321  Contact information holding unit 
           331  Gripping force decision unit 
           341  Control parameter storage unit 
           342  Control parameter 
           351  Task assignment unit 
           352  Slip direction designation unit 
           361  Environment recognition unit 
           401  Shear displacement amount distribution detection unit 
           402  Shear displacement amount distribution calculation unit 
           403  Shear force distribution calculation unit 
           404  Distribution information processing unit 
           405  Sticking ratio calculation unit 
           406  Target sticking ratio setting unit 
           411  Distribution information storage unit 
           412  Distribution time-series information processing unit 
           431  Object 
           441  Friction coefficient measurement unit 
           461  Object 
           471  Angle/position detection unit 
           472  Target position indication unit 
           473  Position control unit 
           474  Output decision unit 
           481  Finger unit 
           482  Orientation information providing unit 
           483  Slip direction calculation unit 
           484  Gripping force calculation unit