Patent Publication Number: US-10307212-B2

Title: Medical manipulator and control method of medical manipulator

Description:
This application is a continuation application based on PCT Patent Application No. PCT/JP2014/052370, filed Jan. 28, 2014, whose priority is claimed on US Provisional Patent Application No. 61/757,427, filed Jan. 28, 2013. The contents of both the PCT Patent Application and the US Provisional patent application are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a medical manipulator used while inserted into a body cavity, and a control method of controlling the medical manipulator. 
     Description of Related Art 
     Recently, in order for a doctor to easily perform surgery, research on a medical treatment using a manipulator that can be deformed in various forms such as a bending motion, a moving motion, or the like, has been carried out. In order to reduce a stress on a patient during surgery, performing surgery after the introduction of an insertion section from an opening formed in a body wall into a body cavity or the like has been considered. 
     For example, an endoscopic surgical instrument disclosed in PCT International Publication No. WO 2007/097034 is constituted by a trocar for endoscopic surgery, a processor, a display, and a treatment tool. 
     The trocar is a guide member having a hollow shaft passing through a body wall. A connecting member is attached to a distal end section of the hollow shaft by a connecting pin. The connecting member has a telescopic structure including a main body section near the connecting pin and a slider slidably inserted into the main body section. As a protrusion amount of the slider with respect to the main body section is controlled, a length of the connecting member can be varied. An imaging device (an imaging section) is turnably attached to a distal end section of the slider by the connecting pin. An output signal of the imaging device is input into the processor. 
     The connecting member is turned about the connecting pin by a motor, an expansion/contraction amount of the connecting member is controlled, and the imaging device is turned about the connecting pin. The processor includes a signal processor configured to process a signal from the imaging device, a control circuit configured to calculate a protrusion amount or the like of the connecting member, and a driving circuit configured to drive the motor. The signal processor has an inclination detector configured to calculate an inclination amount of the hollow shaft when the hollow shaft is inclined about a substantial center of a portion thereof passing through the body wall as a support point. The control circuit calculates a turning amount and the expansion/contraction amount of the connecting member such that the imaging device is disposed at substantially the same position before and after the hollow shaft is inclined, using the inclination amount calculated by the inclination detector. The driving circuit swivels and expands/contracts the connecting member, and swivels the imaging device. 
     In the treatment tool, a rigid treatment tool insertion section extends from the manipulation unit manipulated by an operator such as a doctor or the like and is exchangeably inserted into the trocar. A treatment section such as a pair of gripping forceps is provided at a distal end of the treatment tool insertion section. A handle configured to open and close the pair of gripping forceps and a manipulation device such as a button or the like configured to manipulate the above-mentioned motor are provided at the manipulation unit. 
     Effects of the endoscopic surgical instrument having the above-mentioned configuration are as follows. The operator manipulates the manipulation device to dispose the hollow shaft, the connecting member, and the imaging device on the same axis. These are inserted into the body cavity through the trocar. When the operator manipulates the manipulation unit and the hollow shaft is inclined using the body wall as a support point, the above-mentioned control circuit and driving circuit swivel the imaging device. For this reason, the imaging device can maintain a state in which the observation images are substantially matched on a display screen of the display while being affected little due to inclination of the hollow shaft. 
     SUMMARY OF THE INVENTION 
     According to a first aspect of the present invention, a medical manipulator includes: an insertion section configured to be inserted into a body and having a main movable section configured to be movable and a distal end rigid section provided closer to a distal end of the insertion section than the main movable section; a manipulator having a distal end section at which a treatment section is provided; an auxiliary movable section configured to move the treatment section with respect to the distal end rigid section with at least one degree of freedom; an imaging section configured to be movable with respect to the distal end rigid section and configured to acquire an image in a field-of-vision range; a manipulation unit configured to output an instruction that specifies a position to which the treatment section is moved; a display configured to display the image; a determination unit configured to determine whether a condition is a partial movement condition in which only moving the auxiliary movable section is required or an entire movement condition in which both of moving the auxiliary movable section and moving the main movable section are required, in order to move the treatment section to the position specified in the instruction when the determination unit receives the instruction; and a driving unit configured to drive the auxiliary movable section, the main movable section, and the imaging section based on the partial movement condition or the entire movement condition determined by the determination unit. The driving unit has a field-of-vision fixing mode in which, when the determination unit determines that the condition is the entire movement condition, the driving unit moves the auxiliary movable section and the main movable section so as to move the treatment section to the position specified in the instruction and the driving unit moves the imaging section such that a target area of a test object is projected in a reference area that forms a portion of the image. 
     According to a second aspect of the present invention, in the medical manipulator according to the first aspect, the auxiliary movable section may be provided closer to a proximal end of the manipulator than the treatment section. A proximal end section of the manipulator may be attached to the distal end rigid section. 
     According to a third aspect of the present invention, in the medical manipulator according to the first aspect, the auxiliary movable section may be provided at the insertion section. The manipulator may be inserted into a channel formed in the distal end rigid section so as to advance and retract. 
     According to a fourth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the third aspect, the driving unit may move the imaging section based on a movement amount by which the main movable section is moved when the determination unit determines that the condition is the entire movement condition. 
     According to a fifth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the fourth aspect, a size of the reference area may be capable of being varied. 
     According to a sixth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the fifth aspect, the target area of the test object may be capable of being set by an operator. 
     According to a seventh aspect of the present invention, in the medical manipulator according to any one of the first aspect to the sixth aspect, the target area of the test object may be set to a portion of the test object projected to a center of the image when a confirmation instruction is input by an operator. 
     According to an eighth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the seventh aspect, the driving unit may have a field-of-vision non-fixing mode in which, when the determination unit determines that the condition is the entire movement condition, the driving unit moves the auxiliary movable section and the main movable section so as to move the treatment section to the position specified in the instruction and the driving unit does not automatically move the imaging section. The driving unit may be configured to be set to one of the field-of-vision fixing mode and the field-of-vision non-fixing mode and may be configured to be capable of being switched from the one of the field-of-vision fixing mode and the field-of-vision non-fixing mode to another of the field-of-vision fixing mode and the field-of-vision non-fixing mode. 
     According to a ninth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the eighth aspect, the driving unit may move the imaging section based on the image when the determination unit determines that the condition is the entire movement condition. 
     According to a tenth aspect of the present invention, in the medical manipulator according to any one of the first aspect to the ninth aspect, the instruction output from the manipulation unit may specify a position and an orientation to which the treatment section is moved. The determination unit may determine whether the condition is the partial movement condition or the entire movement condition by moving the treatment section to the position and the orientation specified in the instruction. The driving unit may move the treatment section to the position and the orientation specified in the instruction. 
     According to an eleventh aspect of the present invention, a control method of controlling a medical manipulator including: an insertion section configured to be inserted into a body and having a main movable section configured to be movable and a distal end rigid section provided closer to a distal end of the insertion section than the main movable section; a manipulator having a distal end section at which a treatment section is provided; an auxiliary movable section configured to move the treatment section with respect to the distal end rigid section with at least one degree of freedom; an imaging section configured to be movable with respect to the distal end rigid section and configured to acquire an image in a field-of-vision range; and a manipulation unit configured to output an instruction that specifies a position to which the treatment section is moved, includes: when the instruction is received, determining whether a condition is a partial movement condition in which only moving the auxiliary movable section is required or an entire movement condition in which both of moving the auxiliary movable section and the main movable section are required in order to move the treatment section to the position specified in the instruction; when the condition is determined as the partial movement condition, moving the auxiliary movable section without moving the main movable section and moving the treatment section to the position specified in the instruction; and when the condition is determined as the entire movement condition, with moving the auxiliary movable section and the main movable section and moving the treatment section to the position specified in the instruction, moving the imaging section such that a target area of a test object is projected in a reference area that forms a portion of the image. 
     According to a twelfth aspect of the present invention, the control method of controlling the medical manipulator according to the eleventh aspect may further include, when the condition is determined as the entire movement condition, moving the imaging section based on a movement amount by which the main movable section is moved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a general view showing a medical manipulator according to a first embodiment of the present invention. 
         FIG. 2  is a block diagram of the medical manipulator according to the first embodiment of the present invention. 
         FIG. 3  is a perspective view of a distal end section of an overtube of the medical manipulator according to the first embodiment of the present invention. 
         FIG. 4  is a view showing a state in which a distal end surface of the overtube is opposite to a target tissue. 
         FIG. 5  is a view showing an example of an image displayed on a display when the distal end surface of the overtube is opposite to the target tissue. 
         FIG. 6  is a view showing a state in which a joint section of a treatment tool of the medical manipulator according to the first embodiment of the present invention is bent. 
         FIG. 7  is a view showing an example of an image displayed on the display when the joint section of the treatment tool is bent. 
         FIG. 8  is a view showing a positional relationship between a reference area and a target area in an image acquired by the medical manipulator according to the first embodiment of the present invention. 
         FIG. 9  is a view showing a state in which the joint section of the treatment tool and an endoscope are bent. 
         FIG. 10  is a view in which the endoscope or the like of the medical manipulator according to the first embodiment of the present invention is modeled. 
         FIG. 11  is a view for describing a bent angle of the endoscope when the endoscope or the like of the medical manipulator according to the first embodiment of the present invention is modeled. 
         FIG. 12  is a view showing a state in which the target area is moved with respect to the reference area in the image acquired by the medical manipulator according to the first embodiment of the present invention. 
         FIG. 13  is a view showing an example of the image displayed on the display when the treatment tool and the endoscope are bent. 
         FIG. 14  is a block diagram of a medical manipulator according to a second embodiment of the present invention. 
         FIG. 15  is a view showing a positional relationship between a reference area and a target area of an image acquired by the medical manipulator in a modified example of the medical manipulator according to the second embodiment of the present invention. 
         FIG. 16  is a view showing a state in which the target area is moved with respect to the reference area in the image acquired by the medical manipulator. 
         FIG. 17  is a perspective view of a distal end section of an overtube according to a modified example of the medical manipulator according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     First Embodiment 
     Hereinafter, a medical manipulator according to a first embodiment of the present invention is described with reference to  FIGS. 1 to 13 . 
     As shown in  FIGS. 1 to 3 , a medical manipulator  1  according to the embodiment includes an overtube (an insertion section)  10 , a treatment tool (a manipulator)  20 , an endoscope (an imaging section)  30 , a manipulation unit  40 , a display  50 , and a control device  60 . The overtube  10  is inserted into a body. A proximal end section of the treatment tool  20  is attached to a distal end rigid section  11  disposed at a distal end of the overtube  10 . The endoscope  30  is configured to be movable with respect to the distal end rigid section  11 . The manipulation unit  40  is manipulated by an operator O such as a doctor or the like to output a manipulation instruction (an instruction). The display  50  displays an image acquired by the endoscope  30 . The control device  60  controls the overtube  10 , the treatment tool  20 , and the endoscope  30  in accordance with the manipulation instruction. 
     The overtube  10  has flexibility. As show in  FIG. 3 , the overtube  10  has the above-mentioned distal end rigid section  11 , a bending section (a main movable section)  12 , and a flexible tube section  13 . The bending section  12  is provided closer to a proximal end of the overtube  10  than the distal end rigid section  11  and is configured to be bendable. The flexible tube section  13  is provided closer to the proximal end than the bending section  12  and has flexibility. 
     The distal end rigid section  11  is formed of a metal such as stainless steel or the like in a columnar shape. The proximal end section of the above-mentioned treatment tool  20  is attached to a distal end surface  11   a  of the distal end rigid section  11 . 
     A mechanism having a known configuration may be used as the bending section  12 . While not shown, the bending section  12  includes a plurality of joint rings turnably connected to each other, and the plurality of joint rings are arranged in parallel in a direction of an axis C 1  of the overtube  10 . Distal end sections of four manipulation wires are connected to the joint ring close to the distal end among the plurality of joint rings at equal angle intervals around the axis C 1 . Proximal end sections of the manipulation wires are respectively connected to bending motors  16  (see  FIG. 2 ) provided at a proximal end section of the overtube  10 . As the proximal end sections of the manipulation wires are pulled by the bending motors  16  in the direction of the axis C 1 , the bending section  12  can be bent in a direction X 1  and a direction X 2  perpendicular to the axis C 1  shown in  FIG. 3 . The direction X 1  and the direction X 2  are perpendicular to each other. In this way, the bending section  12  has two degrees of freedom. 
     A movement amount of the manipulation wire in the direction of the axis C 1  is detected by a traction amount detection sensor  17  (see  FIG. 2 ). The traction amount detection sensor  17  converts the detected movement amount into a signal to output the signal to the control device  60 . 
     As shown in  FIG. 3 , a channel  18  is formed in the overtube  10 . The channel  18  has an opening at the distal end surface  11   a  and extends in the direction of the axis C 1  of the overtube  10 . 
     The treatment tool  20  includes a plurality of tubular bodies  21  disposed in parallel in a longitudinal direction of the treatment tool  20 . The treatment tool  20  is configured such that the adjacent tubular bodies  21  in the longitudinal direction are connected by a joint section (an auxiliary movable section)  22 . As an example, the tubular body  21  and the joint section  22  are formed of a material having an insulating property such as ceramics or the like. As shown in  FIG. 2 , an angle detection sensor  23  and a joint driving motor  24  are provided in the joint section  22 . The angle detection sensor  23  detects an angle formed by the adjacent tubular bodies  21  around an axis C 2  (see  FIG. 3 ) of the joint section  22 . The angle detection sensor  23  is, for example, an encoder, a potentiometer, or the like. The joint driving motor  24  adjusts the angle. The angle detection sensor  23  converts the detected angle into a signal to output the signal to the control device  60 . The joint driving motor  24  is driven by the control device  60 . That is, as a knife  26  is turned by the joint driving motor  24 , the knife  26  can be moved with respect to the distal end rigid section  11  with one degree of freedom. 
     As shown in  FIG. 3 , a proximal end section of the knife (a treatment section)  26  formed in a rod shape is fixed to the tubular body  21  disposed at the distal end side. The knife  26  can be formed of a metal having biocompatibility such as stainless steel or the like. 
     One end section of a wiring  201  shown in  FIG. 2  is connected to the proximal end section of the knife  26 . The wiring  201  is disposed in the tubular body  21  and the joint section  22 . The other end section of the wiring  201  is connected to a high-frequency generator  200  that can output a high-frequency current. The high-frequency generator  200  is connected to the control device  60 . The high-frequency generator  200  outputs a high-frequency current in accordance with the control of the control device  60 . 
     As the joint driving motor  24  is driven, the knife  26  turns around the axis C 2  with respect to the distal end rigid section  11 , and can be moved within a range R 1  shown in  FIG. 3  defined on a reference plane. 
     In the embodiment, an example in which the treatment tool  20  includes one joint section  22  is described for the convenience of description. However, the number of joint sections  22  included in the treatment tool  20  is not limited, and the treatment tool  20  may include two or more joint sections  22 . In this case, the manipulator has a multi joint structure. For this reason, the knife  26  can be moved with respect to the distal end rigid section  11  with two degrees of freedom or more. Like the above-mentioned bending section  12 , the treatment tool  20  may be configured such that the plurality of joint rings (segments) are turnably connected. 
     While not shown in detail, in the endoscope  30 , the multi joint structure constituted by the above-mentioned plurality of joint rings is provided in an imaging section main body  31  formed of a flexible material such as silicon or the like in a columnar shape. The distal end section of the manipulation wire (not shown) is connected to the joint ring close to the distal end among the plurality of joint rings. A driving shaft of a bending motor  33  shown in  FIG. 2  is connected to the proximal end section of the manipulation wire. A number of revolutions of the driving shaft of the bending motor  33  is detected by an angle detection sensor  34 . The number of revolutions detected by the angle detection sensor  34  is output to the control device  60 . 
     A lighting unit  35  having an LED, and an imaging unit  36  having a CCD or the like are provided at a distal end surface  31   a  of the imaging section main body  31  while the lighting unit  35  and the imaging unit  36  are exposed to the outside. The lighting unit  35  illuminates a forward side of the endoscope  30  by receiving power from a power supply  66  (to be described below). The imaging unit  36  can acquire an image in a predetermined field-of-vision range R 3  defined in front of the endoscope  30 . The imaging unit  36  converts the image into a signal to output the signal to the control device  60 . 
     The endoscope  30  is inserted into the channel  18  of the overtube  10  and is maintained in a state in which a distal end section of the endoscope  30  protrudes from the distal end rigid section  11  toward a forward side thereof. A plurality of joint rings are also provided in a portion of the imaging section main body  31  protruding from the distal end rigid section  11  toward the forward side thereof. As the bending motor  33  is driven to advance and retract the manipulation wire, the imaging section main body  31  protruding from the distal end rigid section  11  toward the forward side thereof can be bent in a predetermined shape. 
     As shown in  FIGS. 1 and 2 , the manipulation unit  40  has a pair of manipulation arms  42  and  43  attached to a manipulation table  41 , and a foot switch  44  disposed on a floor F. 
     The manipulation arms  42  and  43  have a multi joint structure. The manipulation arm  42  is configured to manipulate the bending section  12  of the overtube  10  to be bent, and manipulate a position and an orientation (a direction) of the knife  26  of the treatment tool  20 . The manipulation arm  43  is configured to manipulate the endoscope  30  to be bent. When the manipulation arms  42  and  43  are manipulated, the manipulation instruction is output to the control device  60 . 
     A switching lever  42   a  for a manipulation arm mode shown in  FIG. 2  is provided at a distal end section of the manipulation arm  42 . As the switching lever  42   a  is manipulated, a manipulation arm mode switching signal is output to a driving amount calculator  67  (to be described below) of the control device  60 . Accordingly, a manipulation arm control mode of the driving amount calculator  67  is switched between a bending section manipulation mode and a knife manipulation mode. In the bending section manipulation mode, a target controlled by the manipulation arm  42  is the bending section  12  of the overtube  10 . In the knife manipulation mode, the target controlled by the manipulation arm  42  is the knife  26  of the treatment tool  20 . 
     A power connecting lever  43   a  configured to output a high-frequency current from the above-mentioned high-frequency generator  200  is provided at a distal end section of the manipulation arm  43 . 
     The foot switch  44  includes a changeover switch  44   a  for an imaging section control mode and a confirmation switch  44   b . The changeover switch  44   a  is used to switch the imaging section control mode of the driving amount calculator  67  (to be described below). The confirmation switch  44   b  is used to allow the operator O to input a confirmation instruction or the like. As the changeover switch  44   a  is manipulated, an imaging section control mode switching signal is output to the driving amount calculator  67 . Accordingly, the imaging section control mode of the driving amount calculator  67  is switched between a field-of-vision fixing mode and a field-of-vision non-fixing mode. In the field-of-vision fixing mode, the endoscope  30  can be automatically manipulated to be bent. In the field-of-vision non-fixing mode, the endoscope  30  cannot be automatically manipulated to be bent. 
     As shown in  FIG. 1 , the display  50  is disposed at a position opposite to the operator O when the manipulation arms  42  and  43  are gripped by his/her hands. The display  50  is connected to the control device  60 . 
     As shown in  FIG. 2 , the control device  60  has a determination unit  62 , a driving unit  63 , a position detector  64 , an image processor  65  for display, and the power supply  66 . The determination unit  62 , the driving unit  63 , the position detector  64 , and the image processor  65  are connected to a bus  61 . The bending motor  16  and the traction amount detection sensor  17  of the overtube  10 , the angle detection sensor  23  and the joint driving motor  24  of the treatment tool  20 , the bending motor  33 , the angle detection sensor  34 , and the imaging unit  36  of the endoscope  30 , the manipulation arms  42  and  43 , the switching lever  42   a , the power connecting lever  43   a , and the foot switch  44  of the manipulation unit  40 , and the display  50  are connected to the bus  61 . 
     Each of the determination unit  62 , the driving unit  63 , the position detector  64 , and the image processor  65  is constituted by a calculation element, a memory, a control program, and so on. Hereinafter, first, the position detector  64  is described. 
     A table showing a bending amount of the bending section  12  with respect to a movement amount of the manipulation wire, a length of the distal end rigid section  11  of the overtube  10 , a length of the tubular body  21  of the treatment tool  20 , a length of the knife  26  of the treatment tool  20 , a length of the joint ring of the endoscope  30 , a direction of the field-of-vision range R 3  with respect to the lighting unit  35 , and so on, are stored in the memory of the position detector  64 . 
     The calculation element of the position detector  64  calculates the bending amount of the bending section  12  and a movement amount of the distal end surface  11   a  of the overtube  10  based on the movement amount detected by the traction amount detection sensor  17 , the table stored in the memory, and so on. The calculation element of the position detector  64  calculates a shape of the treatment tool  20 , a position of the knife  26  of the treatment tool  20  with respect to the distal end surface  11   a  of the overtube  10 , and so on, based on the angle detected by the angle detection sensor  23  of the treatment tool  20  and the values stored in the memory. The calculation element of the position detector  64  calculates a shape of the endoscope  30 , a position of the distal end surface  31   a  of the endoscope  30  with respect to the distal end surface  11   a  of the overtube  10 , and so on, based on the angle detected by the angle detection sensor  34  of the endoscope  30  and the values stored in the memory. The calculation element of the position detector  64  calculates the field-of-vision range R 3  with respect to the distal end surface  11   a  of the overtube  10  based on the position of the distal end surface  31   a  and the values stored in the memory. 
     A driving amount detector configured to detect the position of the knife  26  and the position of the distal end surface  31   a  of the endoscope  30  is constituted by the angle detection sensors  23  and  34  and the position detector  64 . 
     As shown in  FIG. 2 , the driving unit  63  includes the driving amount calculator  67 , an overtube driving unit  68 , a treatment tool driving unit  69  and an endoscope driving unit  70 . 
     As described above, the driving amount calculator  67  has the bending section manipulation mode and the knife manipulation mode in the manipulation arm control mode. The driving amount calculator  67  has the field-of-vision fixing mode and the field-of-vision non-fixing mode in the imaging section control mode. 
     The driving amount calculator  67  recognizes the manipulation instruction output from the manipulation arm  42  as an instruction to bend the bending section  12  of the overtube  10  when the manipulation arm control mode is the bending section manipulation mode. The driving amount calculator  67  outputs a signal specifying the bending motor  16  to be driven and the driving amount thereof to the overtube driving unit  68  based on the manipulation instruction. 
     Meanwhile, the driving amount calculator  67  recognizes the manipulation instruction output from the manipulation arm  42  as an instruction showing a position and an orientation to which the knife  26  is moved when the manipulation arm control mode is the knife manipulation mode. 
     The driving amount calculator  67  calculates the driving amount of the joint driving motor  24  through known inverse kinematics calculation and so on when the determination unit  62  determines that the condition is a partial movement condition as described below. The partial movement condition is a condition in which, when the knife  26  is moved based on the manipulation instruction, the knife  26  can be moved by only turning the joint section  22  of the treatment tool  20  without bending the bending section  12  of the overtube  10 . The driving amount calculator  67  outputs a signal specifying the calculated driving amount of the joint driving motor  24  to the treatment tool driving unit  69 . 
     On the other hand, when the determination unit  62  determines that the condition is the entire movement condition, the driving amount calculator  67  calculates driving amounts of the joint driving motor  24  and the bending motor  16  through inverse kinematics calculation. The entire movement condition is a condition in which, when the knife  26  is moved based on the manipulation instruction, both of turning the joint section  22  of the treatment tool  20  and bending the bending section  12  of the overtube  10  are required. The driving amount calculator  67  outputs signals specifying the calculated driving amounts of the joint driving motor  24  and the bending motor  16  to the treatment tool driving unit  69  and the endoscope driving unit  70 , respectively. Here, when the above-mentioned imaging section control mode is the field-of-vision non-fixing mode, the endoscope  30  is not automatically bent. When the imaging section control mode is the field-of-vision fixing mode, the endoscope  30  is automatically bent depending on the condition. 
     The overtube driving unit  68 , the treatment tool driving unit  69 , and the endoscope driving unit  70  are drivers configured to drive the bending motor  16  of the overtube  10 , the joint driving motor  24  of the treatment tool  20 , and the bending motor  33  of the endoscope  30 , respectively. The overtube driving unit  68 , the treatment tool driving unit  69 , and the endoscope driving unit  70  drive the bending motor  16 , the joint driving motor  24 , and the bending motor  33  based on the signals output from the driving amount calculator  67 , respectively. 
     The determination unit  62  acquires the position and orientation to which the knife  26  recognized by the driving amount calculator  67  is moved, when the imaging section control mode of the driving amount calculator  67  is the field-of-vision fixing mode and the manipulation arm control mode is the knife manipulation mode. The determination unit  62  determines whether the condition is the partial movement condition in which only turning the joint section  22  of the treatment tool  20  is required or the entire movement condition in which both of turning the joint section  22  of the treatment tool  20  and bending the bending section  12  of the overtube  10  are required, in order to move the knife  26  to match the position and orientation of the knife  26  with the command values of the acquired position and orientation, through inverse kinematics calculation. The determination unit  62  outputs the determined movement condition to the driving amount calculator  67 . That is, in the case of the manipulation instruction to move the knife  26  with respect to the distal end rigid section  11  within the range R 1 , for example, when the manipulation amount of the manipulation arm  42  is relatively small, the determination unit  62  determines that the condition is the partial movement condition. The driving amount calculator  67  turns the joint section  22  of the treatment tool  20  by the treatment tool driving unit  69  without bending the bending section  12 . Meanwhile, in the case of the manipulation instruction of moving the knife  26  with respect to the distal end rigid section  11  beyond the range R 1 , for example, when the manipulation amount of the manipulation arm  42  is relatively large, the determination unit  62  determines that the condition is the entire movement condition. The driving amount calculator  67  bends the bending section  12  of the overtube  10  while turning the joint section  22  of the treatment tool  20  by the treatment tool driving unit  69  and the endoscope driving unit  70 . 
     The image processor  65  appropriately converts the image signal output from the imaging unit  36  to output the converted image signal to the display  50 . 
     The power supply  66  supplies the power input from the outside to the overtube  10 , the treatment tool  20 , the endoscope  30 , the manipulation unit  40 , the display  50 , the determination unit  62  of the control device  60 , and so on. 
     Next, surgery using the medical manipulator  1  according to the embodiment having the above-mentioned configuration is described focusing on a control method of the medical manipulator  1  used when the knife  26  is moved. Hereinafter, while the case in which a target tissue formed in an inner wall of the large intestine (a test object) is treated is described, the target area is not limited thereto. For example, the target area may be a hollow organ such as the esophagus, the stomach, the duodenum, the small intestine, the uterus, the bladder, and so on. 
     As shown in  FIG. 1 , an assistant (not shown) lays a patient P on a surgical table  71  beside which the manipulation unit  40  is disposed, and performs appropriate treatment such as sterilization, anesthesia, and so on. When the medical manipulator  1  is started, power is supplied from the power supply  66  to the overtube  10 , the treatment tool  20 , the endoscope  30 , the manipulation unit  40 , the display  50 , the determination unit  62  of the control device  60 , and so on. 
     The operator O manipulates the changeover switch  44   a  of the foot switch  44  to switch the imaging section control mode to the field-of-vision non-fixing mode. The operator O manipulates the switching lever  42   a  to switch the manipulation arm control mode to the knife manipulation mode. The operator O manipulates the manipulation arm  42  to deform the treatment tool  20  in a straight shape along the axis C 1  as shown in  FIG. 4 . The operator O manipulates the manipulation arm  43  to deform the endoscope  30  in a straight shape along the axis C 1 . 
     The operator O manipulates the switching lever  42   a  to switch the manipulation arm control mode to the bending section manipulation mode. The operator O manipulates the changeover switch  44   a  of the foot switch  44  to switch the imaging section control mode to the field-of-vision fixing mode. 
     The operator O illuminates a forward side of the endoscope  30  by supplying power from the power supply  66  to the imaging unit  36 . The operator O grips the manipulation arms  42  and  43  and checks the image in front of the endoscope  30  acquired by the imaging unit  36  through the display  50 . 
     The operator O instructs the assistant to introduce the overtube  10  into the large intestine P 1  from the anus of the patient P as shown in  FIG. 4 . When the operator O manipulates the manipulation arm  42  to bend the bending section  12  of the overtube  10 , the manipulation instruction is output from the manipulation arm  42 . In the driving amount calculator  67 , since the manipulation arm control mode is the bending section manipulation mode, the bending motor  16  is driven based on the manipulation instruction, and the bending section  12  is bent. Accordingly, a direction of the distal end surface  11   a  of the overtube  10  and directions of the treatment tool  20  and the endoscope  30  protruding forward from the distal end surface  11   a  are varied with respect to the flexible tube section  13  of the overtube  10 . 
     The operator O instructs the assistant to stop introduction of the overtube  10  when the distal end surface  11   a  of the overtube  10  is opposite to a target tissue P 2  in the large intestine P 1 . The operator O adjusts a distance between the target tissue P 2  of the large intestine P 1  and the distal end surface  11   a  to a predetermined value. Here, the image G 1  on which the target tissue P 2  of the large intestine P 1  is projected as shown in  FIG. 5  is displayed on the display  50 . 
     The operator O operates the switching lever  42   a  to switch the manipulation arm control mode to the knife manipulation mode. Here, for example, when the operator O manipulates the manipulation arm  42  by a relatively small manipulation amount in which the knife  26  is moved within the range R 1  as described above, the manipulation instruction output from the manipulation arm  42  is recognized as the position and orientation to which the knife  26  is moved by the driving amount calculator  67 . 
     The determination unit  62  determines whether the condition is the partial movement condition or the entire movement condition in order to move the knife  26  to match the position and orientation of the knife  26  with the command values of the acquired position and orientation through the inverse kinematics calculation (a movement condition determination process). In this case, the determination unit  62  determines that the condition is the partial movement condition in which the manipulation amount of the manipulation arm  42  is relatively small, that is, only turning the joint section  22  is required, without bending the bending section  12 . 
     The driving amount calculator  67  of the driving unit  63  to which the movement condition is output as the partial movement condition from the determination unit  62  drives the joint driving motor  24  using the treatment tool driving unit  69 . As shown in  FIG. 6 , the driving amount calculator  67  turns the joint section  22  only and moves the knife  26  to the position and orientation specified in the manipulation instruction using the joint driving motor  24 , without bending the bending section  12  (a partial movement process). Here, since the endoscope  30  is not moved, as shown in  FIG. 7 , an image G 2  in which the treatment tool  20  is relatively slightly moved with respect to the target tissue P 2  with no movement of the target tissue P 2  is displayed on the display  50 . 
     Meanwhile, for example, the operator O manipulates the manipulation arm  42  by a relatively large manipulation amount in which the knife  26  is moved beyond the range R 1  as described above from a state in which the treatment tool  20  is in a straight shape. In this case, in the above-mentioned movement condition determination process, the determination unit  62  determines that the condition is the entire movement condition in which the manipulation amount of the manipulation arm  42  is relatively large, that is, both of turning the joint section  22  and bending the bending section  12  of the overtube  10  are needed. 
     When the determination unit  62  determines that the condition is the entire movement condition, the driving amount calculator  67  automatically sets a portion of the large intestine P 1  projected to a central part of a reference area G 5  that forms a portion of an image G 4  shown in  FIG. 8  acquired by the imaging unit  36  as a target area P 3 . In  FIG. 8 , pixels G 7  that constitute the image G 4  are shown. In  FIGS. 8 and 12  (to be described below), the treatment tool  20  is not shown. The reference area G 5  is constituted by nine pixels G 7  configured in a rectangular shape as a whole. The reference area G 5  is set to a central part of the image G 4 . 
     The driving amount calculator  67  drives the joint driving motor  24  and the bending motor  16  using the treatment tool driving unit  69  and the overtube driving unit  68  to turn the joint section  22  and bend the bending section  12  as shown in  FIG. 9 . Accordingly, the driving amount calculator  67  moves the knife  26  to the position and orientation specified in the manipulation instruction. Simultaneously, as shown in  FIG. 8 , the driving amount calculator  67  bends the endoscope  30  such that the target area P 3  of the large intestine P 1  is projected in the reference area G 5  (an entire movement process). 
     When the bending section  12  is bent, a portion of the endoscope  30  in the vicinity of the distal end surface  11   a  is also moved as shown in  FIG. 9 . As the endoscope  30  is bent such that the distal end surface  31   a  is opposite to the target area P 3 , the image G 4  can be adjusted such that a portion of the target area P 3  of the large intestine P 1  projected in the image G 4  does not depart from the reference area G 5 . In the embodiment, the movement amount of the manipulation wire is detected by the traction amount detection sensor  17 . A relationship between the movement amount of the manipulation wire and the bending amount of the bending section  12  is stored in the position detector  64 . The driving amount calculator  67  calculates the bending amount of the bending section  12  of the overtube  10  from these movement amounts and the table. As a distance between the target tissue P 2  and the distal end surface  11   a  becomes a predetermined value, the driving amount calculator  67  can make an adjustment such that the target area P 3  in the image G 4  does not depart from the reference area G 5 . 
     Here, an angle to which the endoscope  30  is bent is described using a model in which the medical manipulator  1  shown in  FIG. 10  is simplified. 
     The endoscope  30  formed in the straight shape and the target area P 3  of the large intestine P 1  are disposed on the axis C 1  of the overtube  10 . The endoscope  30  is configured by connecting adjacent joint rings  30   a  and  30   b  in the longitudinal direction using a pin  30   c . In  FIGS. 10 and 11 , the joint rings  30   a  and  30   b  are shown in a rod shape. A proximal end section of the joint ring  30   b  is attached to the distal end surface  11   a  of the overtube  10 . That is, the endoscope  30  of the model has one degree of freedom. 
     Here, a length from the pin  30   c  to a bending center Q of the bending section  12  is La, and a length from the target area P 3  to the bending center Q is Lb. 
     In a state in which a position of the flexible tube section  13  with respect to the target area P 3  is fixed, as shown in  FIG. 11 , the bending section  12  is bent to an angle θa. Here, a length Lc from the target area P 3  to the pin  30   c  and an angle θb to which the pin  30   c  is turned such that a distal end of the joint ring  30   a  is opposite to the target area P 3  are expressed as Equation 1 and Equation 2. A unit of the angles θa and θb is radians. 
     
       
         
           
             
               
                 
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     When the bending section  12  of the overtube  10  is bent without bending the endoscope  30 , in the image G 4  shown in  FIG. 8 , the target area P 3  and the target tissue P 2  are moved as shown in  FIG. 12 . In the embodiment, as the endoscope  30  is bent based on the movement amount of the manipulation wire, the target area P 3  is moved to the central part of the reference area G 5  as shown in  FIG. 8 . 
     In the entire movement process, when the endoscope  30  is bent simultaneously while the joint section  22  is turned and the bending section  12  is bent, an image G 9  as shown in  FIG. 13  is displayed on the display  50 . That is, while the treatment tool  20  is relatively largely moved with respect to the target tissue P 2 , projection to the center of the image G 9  before and after turning the joint section  22  and so on is not varied. 
     Accordingly, the control method of the medical manipulator  1  according to the embodiment is terminated. After that, as necessary, the operator O manipulates the manipulation arm  43  to bend the endoscope  30 , and adjusts the field-of-vision range R 3 . The operator O manipulates the power connecting lever  43   a  to output the high-frequency current from the high-frequency generator  200 . The operator O manipulates the manipulation arm  42  and brings the knife  26  in contact with the target tissue P 2  to incise the target tissue P 2 . 
     In the case in which the endoscope  30  is not automatically bent when the manipulation arm control mode is switched to the knife manipulation mode, the changeover switch  44   a  is manipulated to switch the imaging section control mode to the field-of-vision non-fixing mode. 
     The operator O deforms the treatment tool  20  and the endoscope  30  in a straight shape along the axis C 1 . The operator O instructs the assistant to extract the overtube  10  from the large intestine P 1 . After that, the operator O performs necessary treatment, and a series of surgical procedure is terminated. 
     According to the medical manipulator  1  and the control method of the medical manipulator  1  according to the embodiment, in the case in which the manipulation unit  40  is manipulated to move the knife  26  within the range R 1 , or the like, when the determination unit  62  determines that the condition is the partial movement condition, the endoscope  30  is not moved because the bending section  12  of the overtube  10  is not bent. Meanwhile, in the case in which the knife  26  is moved beyond the range R 1 , or the like, when the determination unit  62  determines that the condition is the entire movement condition, while the bending section  12  is bent, the endoscope  30  is bent such that the target area P 3  is projected in the reference area G 5  of the image G 4 . 
     For this reason, movement of the image displayed on the display  50  can be suppressed. In particular, since the endoscope  30  is not moved when the knife  26  is moved within the range R 1 , the operator O can easily recognize the image displayed on the display  50 . 
     The endoscope  30  is bent based on the movement amount of the manipulation wire detected by the traction amount detection sensor  17 . For this reason, the direction of the endoscope  30  can be easily and rapidly adjusted, for example, without calculation of the image processing for detecting the position of the target area P 3  in order to adjust the direction of the endoscope  30 . 
     The driving amount calculator  67  of the driving unit  63  has the field-of-vision fixing mode and the field-of-vision non-fixing mode in the imaging section control mode. The driving amount calculator  67  is configured such that these modes can be switched by the changeover switch  44   a  of the foot switch  44 . As the imaging section control mode is configured as described above, switching between when only the knife  26  of the treatment tool  20  is moved without moving the image (the field-of-vision fixing mode) and when the image is moved with the knife  26  (the field-of-vision non-fixing mode) can be performed. For this reason, manipulation performance of the operator O can be improved. 
     Since the orientation of the knife  26  as well as the position of the knife  26  is controlled, a state of the knife  26  in the space can be more precisely controlled. 
     In the embodiment, the target area P 3  is automatically set with respect to a portion of the large intestine P 1  projected to the central part of the reference area G 5  of the image when the determination unit  62  determines that the condition is the entire movement condition. However, the target area P 3  of the large intestine P 1  may be set as the operator O manipulates the confirmation switch  44   b , or the like. 
     Specifically, when the operator O manipulates the confirmation switch  44   b  to input the confirmation instruction, the portion of the large intestine P 1  projected to the center of the image may be set to the target area P 3 . Accordingly, the target area P 3  can be easily set. As the target area P 3  can be set by the operator O, the target area P 3  can be specifically set in accordance with an intention of the operator O. 
     In the modified example, while the portion of the large intestine P 1  projected to the center of the image is set to the target area P 3 , the portion of the image set to the target area P 3  is not limited to the center but may be an edge part, a corner part, or the like. 
     In the embodiment, the endoscope  30  is inserted through the channel  18  of the overtube  10 . However, the proximal end section of the endoscope  30  may be attached to the distal end surface  11   a  of the overtube  10 . 
     A distance sensor configured to measure the distance between the target tissue P 2  of the large intestine P 1  and the distal end surface  11   a  may be provided at the distal end rigid section  11  of the overtube  10  such that the distance between the target tissue P 2  of the large intestine P 1  and the distal end surface  11   a  can be adjusted. 
     Second Embodiment 
     A second embodiment of the present invention is described with reference to  FIGS. 9, 12, and 14 to 16 . In the second embodiment, the same components as the first embodiment are designated by the same reference numerals, description thereof is omitted, and only different points are described. 
     As shown in  FIG. 14 , a medical manipulator  2  according to the embodiment includes an image processor  81  for correction of a target area position provided at the control device  60 , in addition to the components of the medical manipulator  1  according to the first embodiment. 
     The image processor  81  detects a position of the target area P 3  in the image by performing known image processing with respect to the image acquired by the imaging unit  36 . For example, the endoscope  30  is bent when the target area P 3  is moved by a distance L 1  to arrive at the edge part of the reference area G 5  as shown in  FIG. 12  from a state in which the target area P 3  is disposed at the central part of the reference area G 5  as shown in  FIG. 8 , and the target area P 3  is moved to the central part of the reference area G 5  as shown in  FIG. 8 . 
     In the above-mentioned first embodiment, the endoscope  30  is bent based on the movement amount of the manipulation wire detected by the traction amount detection sensor  17 . On the other hand, in the embodiment, the endoscope  30  is bent based on the image acquired by the imaging unit  36 . 
     According to the medical manipulator  2  according to the embodiment having the above-mentioned configuration, when the manipulation unit  40  is manipulated to move the treatment tool  20 , movement of the image displayed on the display  50  can be suppressed and the operator O can easily recognize the image. 
     As the endoscope  30  is bent based on the position of the target area P 3  in the image, for example, even when the manipulation wire is elongated and the relationship of the bending amount of the bending section  12  with respect to the movement amount of the manipulation wire specified in the table stored in the memory is varied, the position of the target area P 3  can be compensated and the target area P 3  can be more precisely moved to the central part of the reference area G 5 . 
     Even when operations of the overtube  10  and the endoscope  30  are complicated, the target area P 3  can be precisely moved to the central part of the reference area G 5 . 
     In the embodiment, the size of the reference area G 5  may be varied. That is, while the reference area G 5  is constituted by nine pixels G 7 , a reference area G 11  shown in  FIG. 15  is constituted by twenty five pixels G 7  configured in a rectangular shape as a whole. In the modified example, the size of the reference area G 11  is set to be larger than that of the reference area G 5 . The reference area G 11  is set to the central part of the image G 4 . 
     For example, the endoscope  30  is bent when the target area P 3  is moved by a distance L 2  to arrive at the edge part of the reference area G 11  as shown in  FIG. 16  from a state in which the target area P 3  is disposed at the central part of the reference area G 11  as shown in  FIG. 15 , and the target area P 3  is moved to the central part of the reference area G 11  as shown in  FIG. 15 . The distance L 2  of this case is larger than the distance L 1 . That is, in the modified example, the time from starting movement of the target area P 3  to starting bending of the endoscope  30  is larger than that in the above-mentioned embodiment. 
     According to the modified example of the medical manipulator  2  having the above-mentioned configuration, as the size of the reference area is adjusted, precision of the endoscope  30  following the movement of the target area P 3  or stability of the operation of the endoscope  30  can be adjusted. That is, while the following precision is decreased as the reference area is increased, the stability of the operation is increased. 
     There are a portion in which the image processing is easily performed and a portion in which the image processing is not easily performed due to a shape, a color, or the like, of the tissue in the large intestine P 1 . The size of the reference area may be set in accordance with ease of the image processing or the like. 
     In the modified example, the size of the reference area G 11  is set to be larger than that of the reference area G 5 . However, the size of the reference area G 11  may be set to be smaller than that of the reference area G 5 . The shape of the reference area G 5  is not limited to the rectangular shape but may be a circular shape. 
     The endoscope  30  is bent when the target area P 3  is moved until arriving at the edge part of the reference area G 5  from a state in which the target area P 3  is disposed at the central part of the reference area G 5 . However, the endoscope  30  may be bent when the target area P 3  is moved to the outside of the reference area G 5  to be spaced a predetermined distance from the reference area G 5  from a state in which the target area P 3  is disposed at the central part of reference area G 5 . 
     In the first embodiment and the second embodiment, a medical manipulator  3  may have a configuration as shown in  FIG. 17 . In the modified example, the concave section  11   b  is formed in the distal end surface  11   a  of the distal end rigid section  11 . A channel  91  opened at the distal end surface  11   a  of the distal end rigid section  11  is formed in the overtube  10 . The channel  91  is formed to extend in the direction of the axis C 1 . 
     A treatment tool  100  has a treatment tool main body  101  formed of a material having flexibility such as a silicon resin or the like in a rod shape. The treatment tool  100  has no joint like the treatment tool  20  according to the first embodiment. A proximal end section of the knife  26  formed in a rod shape is fixed to a distal end surface of the treatment tool main body  101 . 
     The treatment tool  100  is inserted into the channel  91  of the overtube  10  so as to advance and retract. A position of the treatment tool  100  in the direction of the axis C 1  with respect to the channel  91  can be manipulated by a treatment tool advance and retraction motor (an auxiliary movable section) (not shown) provided at the overtube  10 . That is, as the treatment tool  100  is advanced and retracted by the treatment tool advance and retraction motor, the knife  26  can be moved in the direction of the axis C 1  with respect to the distal end rigid section  11  with one degree of freedom. In the modified example, a range in which the knife  26  can be moved with respect to the distal end rigid section  11  is a range R 5 . 
     The driving amount calculator  67  determines whether the condition is the partial movement condition or the entire movement condition not by turning of the joint section  22  of the treatment tool  20  but by advancing and retracting of the treatment tool  100  in the direction of the axis C 1  by the treatment tool advance and retraction motor. The driving unit  63  drives the treatment tool advance and retraction motor to advance and retract the treatment tool  100 , instead of turning the joint section  22  using the joint driving motor  24  of the treatment tool  20 . 
     An endoscope  110  has an imaging unit (not shown) provided at a distal end section of an endoscope main body  111  formed in a columnar shape. A field-of-vision range of the imaging unit is a field-of-vision range R 7 . 
     The endoscope  110  is disposed at the concave section  11   b  of the distal end rigid section  11 . A proximal end section of the endoscope  110  is turnably supported with respect to the distal end rigid section  11  by a shaft member  116 . An endoscope moving motor is connected to the endoscope  110  via a link mechanism (not shown). As the endoscope moving motor is driven, the endoscope  110  can be turned about the shaft member  116  with respect to the distal end rigid section  11 . 
     In the modified example, the overtube  10  has two degrees of freedom of the bending section  12  and one degree of freedom by advance and retraction in the direction of the axis C 1  thereof, i.e., three degrees of freedom in total. The overtube according to each embodiment of the present invention preferably has at least three degrees of freedom. The treatment tool  100  has one degree of freedom of the advance and retraction in the direction of the axis C 1 . The treatment tool according to each embodiment of the present invention preferably has at least one degree of freedom. The endoscope  110  has one degree of freedom around the shaft member  116 . The endoscope according to each embodiment of the present invention preferably has at least one degree of freedom. 
     Even in the medical manipulator  3  having the above-mentioned configuration, the same effect as the medical manipulator  1  according to the first embodiment is exhibited. 
     In the first embodiment and the second embodiment, the orientation of the knife  26  as well as the position of the knife  26  is controlled. However, only the position of the knife  26  may be controlled. 
     The driving amount calculator  67  may be configured to include only the field-of-vision fixing mode, not including the field-of-vision non-fixing mode in the imaging section control mode. 
     The angle detection sensor  23  and the joint driving motor  24  are provided in the joint section  22  of the treatment tool  20 . However, for example, the joint driving motor  24  may be provided closer to the proximal end than the treatment tool  20  in the distal end rigid section  11  or the like, and the joint section  22  may be turned by a wire (not shown) or the like connected to a driving shaft of the joint driving motor  24 . The number of revolutions of the driving shaft of the joint driving motor  24  is detected by the angle detection sensor  23  such as an encoder or the like, and the angle formed by the adjacent tubular bodies  21  may be calculated from the detected number of revolutions. That is, the angle detection sensor  23  may be provided at a place other than the joint section  22 . 
     While the treatment section is the knife  26 , the kind of treatment section is not limited thereto. As the treatment section, in addition to the knife  26 , a gripping section, a snare, an injection needle, or the like, may be appropriately used. 
     The main movable section is the bending section  12  that can be bent, and the auxiliary movable section is the joint section  22  turned around the axis C 2 . However, moving aspects of the main movable section and the auxiliary movable section may be appropriately selected, and the main movable section or the auxiliary movable section may be moved along the reference line in a straight shape. 
     Hereinabove, while preferred embodiments of the present invention have been described, the present invention is not limited to the embodiments. Additions, omissions, substitutions, and other modifications can be made to the present invention without departing from the scope of the present invention. The present invention is not limited to the above-mentioned description but is limited by only the scope of the appended claims.