MANIPULATOR ARM-TO-PATIENT COLLISION AVOIDANCE USING A NULL-SPACE

摘要

Devices, systems, and methods for avoiding collisions between a manipulator arm and an outer patient surface by moving the manipulator within a null-space. In response to a determination that distance between an avoidance geometry and obstacle surface, corresponding to a manipulator-to-patient distance is less than desired, the system calculates movement of one or more joints or links of the manipulator within a null-space of the Jacobian to increase this distance. The joints are driven according to the reconfiguration command and calculated movement so as to maintain a desired state of the end effector. In one aspect, the joints are also driven according to a calculated end effector displacing movement within a null-perpendicular-space of the Jacobian to effect a desired movement of the end effector or remote center while concurrently avoiding arm-to-patient collisions by moving the joints within the null-space.

主权项

1. A system comprising:
a base; a manipulator arm comprising a proximal portion coupled to the base, a movable distal portion, and a plurality of joints between the base and the distal portion, the plurality of joints together having sufficient degrees of freedom to allow a range of different joint states of the plurality of joints for a given pose of the distal portion of the manipulator arm; an input device; and a processor-based controller coupled to the manipulator arm and to the input device, the controller being configured to perform operations including: receiving a manipulation command from the input device to move the distal portion of the manipulator arm with a first movement at a surgical work site of a patient; calculating a displacing movement of the plurality of joints of the manipulator arm in response to the manipulation command so as to implement the first movement, wherein calculating the displacing movement comprises calculating joint movement within a null-perpendicular space of a Jacobian, the null-perpendicular space being orthogonal to a null-space of the Jacobian; calculating an avoidance movement of the plurality of joints of the manipulator arm within the null-space of the Jacobian so as to implement a clearance between the manipulator arm and an outer surface of the patient within a range of motion of the manipulator arm; and driving the plurality of joints of the manipulator arm according to the displacing movement and the avoidance movement.