Patent Publication Number: US-2021164281-A1

Title: Control system, control apparatus, and control method

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of International Application No. PCT/JP2019/008664, filed on Mar. 5, 2019 and designating the U.S., which claims priority to Japanese Patent Application No. 2018-169214 filed on Sep. 10, 2018. The contents of these applications are incorporated herein by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The disclosures herein relate to a control system, a control apparatus, and a control method. 
     2. Description of the Related Art 
     Conventionally, there is known a technology in which a sensor detects contact between a user and a door handle of a vehicle, and the operation of a door of the vehicle is controlled in accordance with a detection signal output from the sensor. 
     For example, Patent Document 1 describes a technology in which an in-vehicle unit controls the opening of a sliding door of a vehicle when contact between a user and a door handle of the sliding door is detected by a touch sensor installed on the door handle. 
     Further, Patent Document 2 describes a technology in which a control apparatus locks or unlocks a vehicle when contact between a user&#39;s finger and a door handle of the vehicle is detected by a capacitive sensor installed on the door handle. 
     However, in the technology described in Patent Document 1, the sliding door of the vehicle may malfunction if the touch sensor detects the user&#39;s unintended contact. 
     RELATED-ART DOCUMENTS 
     Patent Documents 
     
         
         Patent Document 1: Japanese Laid-Open Patent Publication No. 2007-23620 
         Patent Document 2: Japanese Laid-Open Patent Publication No. 2013-511635 
       
    
     SUMMARY OF THE INVENTION 
     According to at least one embodiment, a control system includes a contact sensor configured to detect contact between an operation body and a door handle, a force sensor configured to detect a force applied by the operation body to the door handle, and a controller configured to control opening or closing of a door when the contact is detected by the contact sensor and the force is detected by the force sensor. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of the exterior of a door handle apparatus according to an embodiment; 
         FIG. 2  is a front view of the door handle apparatus according to the embodiment; 
         FIG. 3  is a rear view of the door handle apparatus according to the embodiment; 
         FIG. 4  is a top view of the door handle apparatus according to the embodiment; 
         FIG. 5  is a perspective view of the exterior of the door handle apparatus (from which a second case is removed) according to the embodiment; 
         FIG. 6  is a front view of the door handle apparatus (from which the second case is removed) according to the embodiment; 
         FIG. 7  is a perspective view of the door handle apparatus (from which the second case is removed) as viewed from the front according to the embodiment; 
         FIG. 8  is a diagram illustrating the inner side of the second case of the door handle apparatus according to the embodiment; 
         FIG. 9  is a partially enlarged view of a metal shaft according to the embodiment; 
         FIG. 10  is a diagram illustrating the stress directions on the metal shaft according to the embodiment; 
         FIG. 11  is a block diagram illustrating a control configuration of the door handle apparatus according to the embodiment; and 
         FIG. 12  is a flowchart of a process performed by a control module according to the embodiment. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     According to at least one embodiment, a control system capable of controlling the opening and closing of a door based on information from sensors in order to avoid an unintended opening/closing operation of the door is provided. 
     In the following, embodiments will be described with reference to the accompanying drawings. 
     [Overview of Door Handle Apparatus  100 ] 
       FIG. 1  is a perspective view of the exterior of a door handle apparatus  100  according to an embodiment.  FIG. 2  is a front view of the door handle apparatus  100  according to the embodiment.  FIG. 3  is a rear view of the door handle apparatus  100  according to the embodiment.  FIG. 4  is a top view of the door handle apparatus  100  according to the embodiment. 
     In the drawings, for the sake of convenience, a Z-axis direction (corresponding to the height direction of a vehicle) is referred to as a vertical direction, a Y-axis direction (corresponding to the width direction of the vehicle) is referred to as a lateral direction, and an X-axis direction (corresponding to the lengthwise direction of the vehicle) is referred to as a longitudinal direction. 
     The door handle apparatus  100  illustrated in  FIG. 1  through  FIG. 4  is integrally formed with an inner panel (not illustrated) of a vehicle door by being fitted into an opening, having approximately the same shape as the door handle apparatus  100 , of the inner panel, and is used to allow a user to open/close the vehicle door. 
     As illustrated in  FIG. 1  through  FIG. 4 , the door handle apparatus  100  includes a body  100 A. The body  100 A forms the external shape of the door handle apparatus  100 . For example, the body  100 A may be formed of a resin material such as an acrylonitrile butadiene styrene (ABS) resin or a polycarbonate (PC) resin. The body  100 A includes a base plate  101 , a door handle case  102 , and a door handle  103 , which are integrally formed. 
     The base plate  101  has a flat plate shape. Further, the base plate  101  supports the door handle case  102  and the door handle  103 , and is fixed to the vehicle door. The door handle case  102  has a flat plate shape. Further, the door handle case  102  is disposed closer to the inside of the vehicle than the base plate  101 , and is coupled to the base plate  101 . The door handle case  102  is exposed to the inside of the vehicle with the door handle apparatus  100  being fitted into the inner panel of the vehicle door. 
     The door handle  103  has a hollow plate shape and extends linearly in the longitudinal direction (the X-axis direction). The door handle  103  is held by the user&#39;s hand when the user performs operations (such as opening/closing of the vehicle door and locking/unlocking of a locking mechanism of the vehicle). The rear end portion (the end portion on the negative X-side) of the door handle  103  is connected to the door handle case  102 , and is integrally formed with the door handle case  102 . The door handle  103  is not movable and is configured to slightly bend and deform in response to an operating force being applied by the user. 
     The body  100 A has a recess  104  that is recessed toward the outside of the vehicle (toward the negative Y-side) in the surroundings of the door handle  103 . With this configuration, the door handle apparatus  100  allows the user to reach the back side of the door handle  103 . Accordingly, both the front side (closer to the inside of the vehicle) and the back side (closer to the outside of the vehicle) of the door handle  103  can be readily held by the user&#39;s hand. 
     [Internal Configuration of Door Handle Apparatus  100 ] 
       FIG. 5  is a perspective view of the exterior of the door handle apparatus  100  (from which a second case  102 B is removed) according to the embodiment.  FIG. 6  is a front view of the door handle apparatus  100  (from which the second case  102 B is removed) according to the embodiment.  FIG. 7  is a perspective view of the door handle apparatus  100  (from which the second case  102 B is removed) as viewed from the front according to the embodiment. 
     As illustrated in  FIG. 5 , the door handle case  102  of the body  100 A can be divided into a first case  102 A disposed closer to the outside of the vehicle, and the second case  102 B disposed closer to the inside of the vehicle. The first case  102 A is fixed to the base plate  101 . Further, the door handle case  102  has a hollow structure. As illustrated in  FIG. 5 , the interior of the door handle case  102  can be exposed by removing the second case  102 B from the first case  102 A. 
     The door handle  103  is provided across the first case  102 A and the second case  102 B. Therefore, as illustrated in  FIG. 5 , when the door handle case  102  is divided into the first case  102 A and the second case  102 B, the door handle  103  can be divided into a first handle  103 A that is integrally formed with the first case  102 A, and a second handle  103 B that is integrally formed with the second case  102 B. 
     As illustrated in  FIG. 5  through  FIG. 7 , a contact sensing unit  110  and a force sensing unit  120  are provided in the interior of the door handle case  102 . 
     The contact sensing unit  110  is an example of a “contact sensor”. The contact sensing unit  110  includes a first capacitance sensor  111  and a second capacitance sensor  112 . Each of the first capacitance sensor  111  and the second capacitance sensor  112  is a thin, flat, rectangular shape and is elongated as viewed in the Y-axis direction in planar view. The first capacitance sensor  111  is stacked on the second capacitance sensor  112  in the Y-axis direction within the door handle  103 . 
     The first capacitance sensor  111  is an example of a “first contact sensor”. The first capacitance sensor  111  is disposed on the back side (on the negative Y-side) of the door handle  103 , and is configured to detect contact of an operation body with the back side of the door handle  103 . Specifically, the first capacitance sensor  111  includes detection electrodes, and upon the operation body contacting the back side of the door handle  103 , the first capacitance sensor  111  outputs a current value corresponding to the capacitance between the operation body and each of the detection electrodes as a first contact detection signal. 
     The second capacitance sensor  112  is an example of a “second contact sensor”. The second capacitance sensor  112  is disposed on the front side (on the positive Y-side) of the door handle  103 , and detects contact of the operation body with the front side of the door handle  103 . Specifically, the second capacitance sensor  112  includes detection electrodes, and upon the operation body contacting the front side of the door handle  103 , the second capacitance sensor  112  outputs a current value corresponding to the capacitance between the operation body and each of the detection electrodes as a second contact detection signal. 
     The force sensing unit  120  includes a metal shaft  121 , a holder  122 , a sensor base  123 , and a strain gauge  124 . The strain gauge  124  is connected to the rear end portion of the metal shaft  121 . Note that the strain gauge  124  is difficult to be seen from the outside, and is indicated by a hidden line in  FIG. 7 . A configuration of the strain gauge  124  will be described later in detail with reference to  FIG. 9 . 
     The metal shaft  121  is an example of a “transmitting member”. The metal shaft  121  is made of metal and has a rod shape. The metal shaft  121  extends linearly in the longitudinal direction (in the X-axis direction) within the door handle case  102 . The metal shaft  121  is configured to transmit a force applied to the door handle  103  to the strain gauge  124 . A middle portion of the metal shaft  121  is supported by the holder  122 , and a front end portion (on the positive X-side) of the metal shaft  121 , located on the front side of the vehicle relative to the middle portion, is disposed within the door handle  103 . Accordingly, the force applied to the door handle  103  is transmitted to the front end portion of the metal shaft  121 , and stress occurs in the front end portion of the metal shaft  121 . The stress occurring in the front end portion of the metal shaft  121  is transmitted to the rear end portion of the metal shaft  121  through a fulcrum (the holder  122 ). The stress transmitted to the rear end portion of the metal shaft  121  is further transmitted to the strain gauge  124  that is connected to the rear end portion of the metal shaft  121 . In the present embodiment, the metal shaft  121  is a round bar, but the present invention is not limited thereto. 
     The holder  122  supports the middle portion of the metal shaft  121  and thus functions as a fulcrum. Specifically, as illustrated in  FIG. 8 , the holder  122  is fixed to the inner surface of the second case  102 B (at a position in the vicinity of the rear end portion of the second handle  103 B). As illustrated in  FIG. 7  and  FIG. 8 , the holder  122  has a through hole  122 A that extends in the longitudinal direction (X-axis direction), and has a circular shape. The inner diameter of the through hole  122 A is approximately the same as the outer diameter of the metal shaft  121 . Further, as illustrated in  FIG. 5  through  FIG. 8 , the metal shaft  121  passes through the through hole  122 A, such that the holder  122  supports the middle portion of the metal shaft  121  with the outer peripheral surface of the metal shaft  121  contacting the inner peripheral surface of the through hole  122 A. In this manner, the holder  122  can support the middle portion of the metal shaft  121  without looseness of the metal shaft  121 . 
     The sensor base  123  is a member that supports the strain gauge  124 . Specifically, as illustrated in  FIG. 8 , the sensor base  123  is fixed to the inner surface of the second case  102 B at a position behind the rear end portion (the end portion on the negative X side) of the metal shaft  121 . A surface  123 A of the sensor base  123  faces the rear end of the metal shaft  121 , and the strain gauge  124  is screwed to the surface  123 A. Accordingly, the sensor base  123  supports the strain gauge  124 , such that the strain gauge  124  is connected to the rear end portion of the metal shaft  121  and can detect stress transmitted to the rear end portion of the metal shaft  121 . 
     The strain gauge  124  is an example of a “force sensor”. The strain gauge  124  detects a force applied to the door handle  103 . Specifically, the strain gauge  124  is disposed facing the rear end portion of the metal shaft  121 . When the force is applied to the door handle  103 , the strain gauge  124  is subjected to stress transmitted from the rear end portion of the metal shaft  121 . As a result, a strain is applied to a metallic resistance material of the strain gauge  124 , thus causing the resistance value to change. Accordingly, the strain gauge  124  outputs a voltage value corresponding to the direction of the strain and loads applied to the strain gauge  124 , via a flexible printed circuit (FPC)  124 A. That is, the strain gauge  124  outputs a force detection signal that indicates the force applied to the door handle  103 . Note that the strain gauge  124  can detect strains in the Y-axis direction and in the Z-axis direction. Therefore, the strain gauge  124  can detect a force applied to the door handle  103  in the Y-axis direction (which corresponds to the lateral direction of the vehicle, and is an example of a “first direction” and a “second direction”), and a force applied to the door handle  103  in the Z-axis direction (which corresponds to the vertical direction of the vehicle, and is an example of a “third direction”). The strain gauge  124  may have a structure similar to that of a pointing stick, for example. 
       FIG. 8  is a diagram illustrating the inner side of the second case  102 B of the door handle apparatus  100  according to the embodiment. As illustrated in  FIG. 8 , a holder portion  103 C is formed on the inner surface of the second handle  103 B of the second case  102 B. The holder portion  103 C has a through hole  103 D that extends in the longitudinal direction (X-axis direction), and has a circular shape. The inner diameter of the through hole  103 D is approximately the same as the outer diameter of the metal shaft  121 . The metal shaft  121  passes through the through hole  103 D, such that the holder portion  103 C supports the front end portion of the metal shaft  121  with the outer peripheral surface of the metal shaft  121  contacting the inner peripheral surface of the through hole  103 D. Accordingly, a force applied to the door handle  103  is transmitted to the front end portion of the metal shaft  121  through the holder portion  103 C. 
     [Configuration of Metal Shaft  121 ] 
       FIG. 9  is a partially enlarged view of the metal shaft  121  according to the embodiment. As illustrated in  FIG. 9 , a joint  121 A having a circular tubular shape is provided at the rear end portion of the metal shaft  121 . The joint  121 A has a circular opening  121 B on the side closer to the strain gauge  124 . The strain gauge  124  having a circular shape is fitted into the opening  121 B of the joint  121 A. In this manner, the metal shaft  121  is connected to the strain gauge  124 , thus allowing a force applied to the door handle  103  to be transmitted to the strain gauge  124 . 
     As illustrated in  FIG. 9 , the force sensing unit  120  according to the present embodiment further includes an elastic member  125 . The elastic member  125  is formed of an elastic material such as rubber or silicone. The elastic member  125  has a through hole  125 A that extends in the longitudinal direction of the vehicle, and has a square shape. A projection  124 B of the strain gauge  124  is fitted into the through hole  125 A of the elastic member  125 , and in this state, the elastic member  125  is fitted to the joint  121 A together with the strain gauge  124 . Accordingly, the force sensing unit  120  according to the present embodiment can transmit a force applied to the door handle  103  to the strain gauge  124  through the elastic member  125 . With this configuration, the elastic member  125  of the force sensing unit  120  according to the present embodiment can reduce assembly error of the joint  121 A of the metal shaft  121 , displacement of the metal shaft  121  due to vibrations of the vehicle, excessive displacement of the metal shaft  121 , and the like. Accordingly, the force sensing unit  120  according to the present embodiment can avoid excessive detection by the strain gauge  124 . Note that if the strain gauge  124  is provided with a cap formed of an elastic material, the cap may be used as the elastic member  125 . 
     [Stress Directions on Metal Shaft  121 ] 
       FIG. 10  is a diagram illustrating the stress directions on the metal shaft  121 . As illustrated in  FIG. 10 , the middle portion of the metal shaft  121  is supported by the holder  122 , and thus, the middle portion of the metal shaft  121  functions as a fulcrum. Therefore, upon a force being applied to the door handle  103 , stress is applied to the front end portion of the metal shaft  121  (the portion on the front end side of the metal shaft  121  relative to the holder  122 ) in a direction same as the direction of the force applied to the door handle  103 , and stress is applied to the rear end portion of the metal shaft  121  (portion on the rear end side of the metal shaft  121  relative to the holder  122 ) in a direction opposite to the direction of the force applied to the door handle  103 . 
     For example, when a force is applied to the door handle  103  in a direction toward the inside of the vehicle, stress is applied to the front end portion of the metal shaft  121  (the portion on the front side of the metal shaft  121  relative to the holder  122 ) in a direction D 1   a  toward the inside of the vehicle, and stress is applied to the rear end portion of the metal shaft  121  (the portion on the rear side of the metal shaft  121  relative to the holder  122 ) in a direction D 1   b  toward the outside of the vehicle as illustrated in  FIG. 10 . In this case, a strain is produced in the strain gauge  124  in the direction Dib. Accordingly, the strain gauge  124  outputs a force detection signal corresponding to the strain produced in the direction D 1   b . That is, the strain gauge  124  outputs a force detection signal indicating that the force is applied to the door handle  103  in the direction toward the inside of the vehicle. 
     Further, when a force is applied to the door handle  103  in a direction toward the outside of the vehicle, stress is applied to the front end portion of the metal shaft  121  (the portion on the front side of the metal shaft  121  relative to the holder  122 ) in a direction D 2   a  toward the outside of the vehicle, and stress is applied to the rear end portion of the metal shaft  121  (the portion on the rear side of the metal shaft  121  relative to the holder  122 ) in a direction D 2  toward the inside of the vehicle as illustrated in  FIG. 10 . In this case, a strain is produced in the strain gauge.  124  in the direction D 2   b . Accordingly, the strain gauge  124  outputs a force detection signal corresponding to the strain produced in the direction D 2   b . That is, the strain gauge  124  outputs a force detection signal indicating that the force is applied to the door handle  103  in the direction toward the outside of the vehicle. 
     Further, when a force is applied to the door handle  103  in a downward direction, stress is applied to the front end portion of the metal shaft  121  (the portion on the front side of the metal shaft  121  relative to the holder  122 ) in a downward direction D 1   a , and stress is applied to the rear end portion of the metal shaft  121  (the portion on the rear side of the metal shaft  121  relative to the holder  122 ) in an upward direction D 3   b  as illustrated in  FIG. 10 . In this case, a strain is produced in the strain gauge  124  in the upward direction D 3   b . Accordingly, the strain gauge  124  outputs a force detection signal corresponding to the strain produced in the upward direction D 3   b . That is, the strain gauge  124  outputs a force detection signal indicating that the force is applied to the door handle  103  in the downward direction. 
     Further, when a force is applied to the door handle  103  in an upward direction, stress is applied to the front end portion of the metal shaft  121  (the portion on the front side of the metal shaft  121  relative to the holder  122 ) in an upward direction D 4   a , and stress is applied to the rear end portion of the metal shaft  121  (the portion on the rear side of the metal shaft  121  relative to the holder  122 ) in a downward direction D 4   b  as illustrated in  FIG. 10 . In this case, a strain is produced in the strain gauge  124  in the downward direction D 4   b . Accordingly, the strain gauge  124  outputs a force detection signal corresponding to the strain produced in the downward direction D 4   b . That is, the strain gauge  124  outputs a force detection signal indicating that the force is applied to the door handle  103  in the upward direction. 
     The force sensing unit  120  according to the present embodiment can adjust the detection sensitivity of the strain gauge  124  by changing the position of the holder  122  with respect to the metal shaft  121  (that is, position of the fulcrum of the metal shaft  121 ). For example, by providing the holder  122  at a position closer to the rear end of the metal shaft  121 , the displacement of the rear end portion of the metal shaft  121  can be decreased. Accordingly, the detection sensitivity of the strain gauge  124  can be lowered. Conversely, by providing the holder  122  at a position closer to the front end of the metal shaft  121 , the displacement of the rear end portion of the metal shaft  121  can be increased. Accordingly, the detection sensitivity of the strain gauge  124  can be enhanced. 
     [Configuration of Control System  10 ] 
       FIG. 11  is a block diagram illustrating a control configuration of the door handle apparatus  100  according to the embodiment. As illustrated in  FIG. 11 , the control system  10  includes the door handle apparatus  100  and a control module  130 . 
     The control module  130  is an example of a “controller” and a “control apparatus”. The control module  130  includes a first acquiring unit  131 , a second acquiring unit  132 , and a control unit  133 . 
     The first acquiring unit  131  acquires a first contact detection signal (a current value corresponding to the capacitance), indicating that the operation body has contacted the back side of the door handle  103 , from the first capacitance sensor  111 . Further, the first acquiring unit  131  acquires a second contact detection signal (a current value corresponding to the capacitance), indicating that the operation body has contacted the front side of the door handle  103 , from the second capacitance sensor  112 . 
     The second acquiring unit  132  acquires a force detection signal (a voltage value corresponding to the direction of the strain and loads), indicating that a force is applied to the door handle  103  by the operation body, from the strain gauge  124 . 
     The control unit  133  controls the opening/closing of the vehicle door and the operation (locking and unlocking) of the locking mechanism of the vehicle, based on the first contact detection signal and the second contact detection signal acquired by the first acquiring unit  131  and the force detection signal acquired by the second acquiring unit  132 . 
     Specifically, when the first contact detection signal and the second contact detection signal are acquired by the first acquiring unit  131  and also the force detection signal is acquired by the second acquiring unit  132 , the control unit  133  controls the opening/closing of the vehicle door and the operation (locking and unlocking) of the locking mechanism of the vehicle in accordance with the direction of a force applied to the door handle  103  identified by the force detection signal. 
     That is, the control unit  133  controls the opening/closing of the vehicle door and the operation (locking and unlocking) of the locking mechanism of the vehicle, when the user&#39;s hand contacts both sides (the front and back sides) of the door handle  103  and also a force is applied by the user&#39;s hand to the door handle  103 . 
     For example, if the direction of the force applied to the door handle  103  identified by the force detection signal is the direction toward the outside of the vehicle (the negative Y-direction), the control unit  133  controls the opening of the vehicle door. For example, when the vehicle door is closed, the control unit  133  performs control such that the vehicle door automatically opens. Further, for example, when the vehicle door is automatically closing, the control unit  133  performs control such that the closing of the door is stopped. 
     Further, if the direction of the force applied to the door handle  103  identified by the force detection signal is the direction toward the inside of the vehicle (the positive Y-direction), the control unit  133  controls the closing of the vehicle door. For example, when the vehicle door is open, the control unit  133  performs control such that the vehicle door is automatically closed. Further, for example, when the vehicle door is automatically opening, the control unit  133  performs control such that the opening of the door is stopped. 
     For example, the control unit  133  may include a control section (not illustrated) configured to control a door opening and closing mechanism (such as a motor), and the control unit  133  may cause the control section to control the door opening and closing by transmitting a control signal to the control section. However, the present invention is not limited thereto, and the control unit  133  may directly control the opening and closing of the door by transmitting a control signal to the door opening and closing mechanism. 
     Further, if the direction of the force applied to the door handle  103  identified by the force detection signal is the downward direction (the negative Z-direction), the control unit  133  performs control for locking the locking mechanism of the vehicle. For example, when the locking mechanism of the vehicle is unlocked, the control unit  133  performs control such that the locking mechanism of the vehicle is automatically locked. 
     Further, if the direction of the force applied to the door handle  103  identified by the force detection signal is the upward direction (the positive Z-direction), the control unit  133  performs control for unlocking the locking mechanism of the vehicle. For example, when the locking mechanism of the vehicle is locked, the control unit  133  performs control such that the locking mechanism of the vehicle is automatically unlocked. 
     For example, the control unit  133  may include a control section (not illustrated) configured to control the locking mechanism (such as a motor), and the control unit  133  may cause the control section to control the locking mechanism of the vehicle by transmitting a control signal to the control section. However, the present invention is not limited thereto, and the control unit  133  may directly control the operation of the locking mechanism of the vehicle by transmitting a control signal to the locking mechanism of the vehicle. 
     In the door handle apparatus  100  according to the present embodiment, each of the first capacitance sensor  111  and the second capacitance sensor  112  includes a plurality of (four, for example) detection electrodes that are arranged in the longitudinal direction of the vehicle, and each of the detection electrodes is configured to output a contact detection signal. For example, the control unit  133  may control the opening or closing of the door or the operation (locking or unlocking) of the locking mechanism of the vehicle, when first contact detection signals are acquired from a predetermined number or more (two or more, for example) of detection electrodes of the first capacitance sensor  111 , second contact detection signals are acquired from a predetermined number or more (two or more, for example) of detection electrodes of the second capacitance sensor  112 , and a force detection signal is acquired from the strain gauge  124 . 
     Further, if the strain gauge  124  detects that a force is applied to the door handle  103  in the vertical direction of the vehicle, the control unit  133  may perform other control (such as controlling a power window) instead of controlling the locking mechanism of the vehicle. For example, if the strain gauge  124  detects that a force is applied to the door handle  103  in the upward direction, the control unit  133  may control the closing of the power window. Conversely, if the strain gauge  124  detects that a force is applied to the door handle  103  in the downward direction, the control unit  133  may control the opening of the power window. 
     For example, the control module  130  includes a central processing unit (CPU), a read-only memory (ROM), a random-access memory (RAM), and an external interface (I/F). For example, the control module  130  may implement the functions illustrated in  FIG. 11  by causing the CPU to execute a program stored in the ROM. The control module  130  may be a microcomputer. 
     [Process Performed by Control Module  130 ] 
       FIG. 12  is a flowchart of a process performed by the control module  130  according to the embodiment. 
     First, the control module  130  determines whether the first acquiring unit  131  has acquired a first contact detection signal from the first capacitance sensor  111  (step S 201 ). In step S 201 , if the control module  130  determines that a first contact detection signal has not been acquired (no in step S 201 ), the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, if the control module  130  determines that a first contact detection signal has been acquired (yes in step S 201 ), the control module  130  determines whether the first acquiring unit  131  has acquired a second contact detection signal from the second capacitance sensor  112  (step S 202 ). In step S 202 , if the control module  130  determines that a second contact detection signal has not been acquired (no in step S 202 ), the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, in step S 202 , if the control module  130  determines that a second contact detection signal has been acquired (yes in step S 202 ), the control module  130  determines whether the second acquiring unit  132  has acquired a force detection signal from the strain gauge  124  (step S 203 ). In step S 203 , if the control module  130  determines that a force detection signal has not been acquired (no in step S 203 ), the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, in step S 203 , if the control module  130  determines that a force detection signal has been acquired (yes in step S 203 ), the control unit  133  determines whether the direction of a force applied to the door handle  103  is the direction toward the outside of the vehicle, based on the force detection signal acquired by the second acquiring unit  132  (step S 204 ). 
     In step S 204 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is the direction toward the outside of the vehicle (yes in step S 204 ), the control unit  133  controls the opening of the vehicle door (step S 205 ). Then, the control module  130  ends the process illustrated in  FIG. 12 . 
     In step S 204 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is not the direction toward the outside of the vehicle (no in step S 204 ), the control unit  133  determines whether the direction of the force applied to the door handle  103  is the direction toward the inside of the vehicle, based on the force detection signal acquired by the second acquiring unit  132  (step S 206 ). 
     In step S 206 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is the direction toward the inside of the vehicle (yes in step S 206 ), the control unit  133  controls the closing of the vehicle door (step S 207 ). Then, the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, in step S 206 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is not the direction toward the inside of the vehicle (no in step S 206 ), the control unit  133  determines whether the direction of the force applied to the door handle  103  is the downward direction (step S 208 ). 
     In step S 208 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is the downward direction (yes in step S 208 ), the control unit  133  controls locking of the vehicle door (step S 209 ). Then, the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, in step S 208 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is not the downward direction (no in step S 208 ), the control unit  133  determines whether the direction of the force applied to the door handle  103  is the upward direction (step S 210 ). 
     In step S 210 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is the upward direction (yes in step S 210 ), the control unit  133  controls the unlocking of the vehicle door (step S 211 ). Then, the control module  130  ends the process illustrated in  FIG. 12 . 
     Conversely, in step S 210 , if the control unit  133  determines that the direction of the force applied to the door handle  103  is not the upward direction (no in step S 210 ), the control module  130  ends the process illustrated in  FIG. 12 . 
     As described above, the control system  10  according to the present embodiment includes the contact sensing unit  110  configured to detect contact between a user&#39;s hand (an operation body) and the door handle  103 , the strain gauge  124  configured to detect a force applied by the user&#39;s hand (the operation body) to the door handle  103 , and the control module  130  configured to control the opening or closing of a door when the contact applied to door handle  103  is detected by the contact sensing unit  110  and the force applied to the door handle  103  is detected by the strain gauge  124 . Accordingly, if the door handle  103  is unintentionally touched, the control system  10  according to the present embodiment does not perform the opening or closing of the door unless the force applied to the door handle  103  is detected at the same time. Therefore, the control system  10  according to the present embodiment can avoid an unintended opening/closing operation of the door. 
     Further, the control system  10  according to the present embodiment includes the rod-shaped metal shaft  121 . The rod-shaped metal shaft  121  is disposed in the door handle  103 , includes the holder  122  (fulcrum) between one end portion and the other end portion of the metal shaft  121 , and transmits the force from the one end portion to the other end portion. The strain gauge  124  detects the force transmitted to the other end portion of the metal shaft  121 . Accordingly, although the door handle  103  is not configured to be movable, the control system  10  according to the present embodiment can securely detect the force applied to the door handle  103 . Further, the control system  10  according to the present embodiment can readily and appropriately adjust the detection sensitivity of the strain gauge  124  in accordance with the required specifications by changing the design of the metal shaft  121  (such as the length, the diameter, the position of the fulcrum, or the material) of the metal shaft  121 . 
     Further, in the control system  10  according to the present embodiment, the contact sensing unit  110  includes the first capacitance sensor  111  disposed on the back side of the door handle  103  and the second capacitance sensor  112  disposed on the front side of the door handle  103 . The control module  130  controls the opening or closing of the door when the contact with the door handle  103  is detected by the first capacitance sensor  111  and by the second capacitance sensor  112  and the force applied to the door handle  103  is detected by the strain gauge  124 . Accordingly, the control system  10  according to the present embodiment controls the opening or closing of the door when the user holds the door handle  103  and the contact between the user and the door handle  103  is detected by both the first capacitance sensor  111  and the second capacitance sensor  112 . That is, the control system  10  according to the present embodiment does not perform the opening or closing of the door when the contact between the user and the door handle  103  is detected by either the first capacitance sensor  111  or the second capacitance sensor  112 . Accordingly, the control system  10  according to the present embodiment can avoid an unintended opening and closing operation of the door. 
     Further, in the control system  10  according to the present embodiment, the control module  13  controls the opening of the door when the strain gauge  124  detects a force applied to the door handle  103  in the direction toward the outside of the vehicle (a force in a first direction corresponding to the direction of opening the door). In addition, the control module  130  controls the closing of the door when the strain gauge  124  detects a force in the direction toward the inside of the vehicle (a force in a second direction corresponding to the direction of closing the door). Accordingly, the control system  10  according to the present embodiment can control the opening or closing of the door in accordance with the user&#39;s intuitive operation with respect to the door handle  103 . 
     In addition, in the control system  10  according to the present embodiment, the strain gauge  124  can detect a force applied to the door handle  103  in the vertical direction of the vehicle. When the strain gauge  124  detects a force applied to the door handle  103  in the vertical direction of the vehicle, the control module  130  can control the locking and unlocking the door. Accordingly, with a relatively simple configuration, the control system  10  according to the present embodiment can detect the user&#39;s operations for opening/closing the door and also for locking/unlocking the door, and can control the opening/closing of the door and also the locking/unlocking of the door. 
     Although specific embodiments have been described above, the present invention is not limited to the above-described embodiments. Variations and modifications may be made to the described subject matter without departing from the scope of the invention as set forth in the accompanying claims. 
     For example, in the above-described embodiments, the door handle  103  extends in the longitudinal direction of the vehicle and the rear end portion of the door handle  103  is connected to the door handle case  102 ; however, the present invention is not limited thereto. A door handle whose front end portion is connected to the door handle case, a door handle whose front end portion and rear end portion are connected to the door handle case, or a door handle extending in the vertical direction of the vehicle may be used. Further, the present invention can be applied to a hinged door, a sliding door, a gull-wing door, and a door of any other type. Further, the present invention can be applied to a door handle inside the vehicle and a door handle outside the vehicle. Further, the present invention can be applied to any door other than the vehicle door. In any case, it is preferable to control the opening/closing of the door when a force is applied to a door handle in a direction corresponding to the direction of opening/closing of the door. For example, a door handle that extends in the vertical direction of the vehicle may be used for a sliding door that slides backward. In this case, when a force applied to the door handle in the backward direction is detected, the opening of the sliding door may be controlled, and when a force in the forward direction is detected, the closing of the sliding door may be controlled. 
     For example, in the above-described embodiments, two force sensing units  120  may be vertically arranged in parallel. In this case, the control unit  133  may detect the twisting of the door handle  103  based on a force detection signal output from a strain gauge  124  (a first strain gauge) of one of the force sensing units  120  and a force detection signal output from a strain gauge  124  (a second strain gauge) of the other force sensing unit  120 . Then, if the twisting of the door handle  103  is detected, the control unit  133  may control the vehicle door (such as controlling the locking mechanism or controlling a power window). For example, if the door handle  103  is twisted, the force detection signal output from the one force sensing unit  120  and the force detection signal output from the other force sensing unit  120  indicate different horizontal directions. Therefore, if the second acquiring unit  132  acquires force detection signals indicating different directions, the twisting of the door handle  103  can be detected. 
     Further, in the above-described embodiments, the control system  10  may further include an authentication device that uses a known authentication method to authenticate a smart key possessed by a user. In this case, the control unit  133  may control the door when the contact with the door handle  103  is detected, the force applied to the door handle  103  is detected, and the smart key is successfully authenticated by the authentication device. 
     Further, in the above-described embodiments, the control system  10  may further include a communication device configured to notify the user that the opening/closing of the door starts to be controlled by sound, light, or vibration when the control system  10  starts to control the opening/closing of the door.