Medical support arm system, medical support arm control method, and medical support arm control device

Abstract

To realize torque control based on an estimated external force and to cope with more various situations. Provided is a medical support arm system including: a support arm that is a multilink structure having a plurality of links connected by a joint unit including an actuator, and configured to support a medical unit; and a control device including an external force estimation unit configured to estimate an external force acting on the joint unit on the basis of a drive characteristic of the actuator, and a joint control unit configured to control drive of the joint unit on the basis of an external torque estimated by the external force estimation unit.

1 . A medical support arm system comprising:
 a support arm that is a multilink structure having a plurality of links connected by a joint unit including an actuator, and configured to support a medical unit; and   a control device including an external force estimation unit configured to estimate an external force acting on the joint unit on a basis of a drive characteristic of the actuator, and a joint control unit configured to control drive of the joint unit on a basis of an external torque estimated by the external force estimation unit.   
     
     
         2 . The medical support arm system according to  claim 1 , wherein
 the external force estimation unit calculates a motion estimation torque related to the drive of the joint unit, and estimates the external torque on a basis of the motion estimation torque.   
     
     
         3 . The medical support arm system according to  claim 2 , wherein
 the external force estimation unit estimates a friction torque related to the drive of the joint unit, and calculates the motion estimation torque on a basis of the friction torque.   
     
     
         4 . The medical support arm system according to  claim 3 , wherein
 the external force estimation unit estimates the friction torque using a model identification result based on a static friction and a dynamic friction of a speed reducer.   
     
     
         5 . The medical support arm system according to  claim 2 , wherein
 the external force estimation unit estimates an internal consumption torque related to the drive of the joint unit, and calculates the motion estimation torque on a basis of the internal consumption torque.   
     
     
         6 . The medical support arm system according to  claim 1 , wherein
 the external force estimation unit estimates the external torque on a basis of a current command torque related to the drive of the joint unit.   
     
     
         7 . The medical support arm system according to  claim 1 , wherein
 the external force estimation unit estimates the external torque on a basis of a phase difference command torque related to the drive of the joint unit.   
     
     
         8 . The medical support arm system according to  claim 1 , wherein
 the joint control unit controls an electromagnetic motor that generates a drive force related to the drive of the joint unit.   
     
     
         9 . The medical support arm system according to  claim 1 , wherein
 the joint control unit controls an ultrasonic motor that generates a drive force related to the drive of the joint unit.   
     
     
         10 . The medical support arm system according to  claim 1 , wherein
 the support arm includes a first joint unit not including a torque sensor and a second joint unit including the torque sensor, and   the joint control unit performs drive control of the first joint unit based on the external torque estimated by the external force estimation unit and drive control of the second joint unit based on an external torque detected by the torque sensor.   
     
     
         11 . The medical support arm system according to  claim 1 , wherein
 the actuator includes a first actuator including an electromagnetic motor that generates a drive force related to the drive of the joint unit, and a second actuator including an ultrasonic motor that generates a drive force related to the drive of the joint unit, and   the joint control unit controls both the first actuator and the second actuator.   
     
     
         12 . A medical support arm control method comprising:
 by a processor, controlling drive of a joint unit including an actuator of a support arm that is a multilink structure having a plurality of links connected by the joint unit; and   estimating an external force acting on the joint unit on a basis of a drive characteristic of the actuator, wherein the controlling further includes controlling the drive of the joint unit on a basis of an estimated external torque.   
     
     
         13 . A medical support arm control device comprising:
 a joint control unit configured to control drive of a joint unit including an actuator of a support arm that is a multilink structure having a plurality of links connected by the joint unit; and   an external force estimation unit configured to estimate an external force acting on the joint unit on a basis of a drive characteristic of the actuator, wherein   the joint control unit controls the drive of the joint unit on a basis of an external torque estimated by the external force estimation unit.