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. In a robotic system comprising a base and a manipulator arm, the 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, and 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 state of the distal portion, a method comprising:
calculating a distal portion displacing movement of the plurality of joints to effect a desired distal portion movement for a desired state of the distal portion within a surgical work site in response to a manipulation command received from a user input, the calculating of the distal portion displacing movement including calculating joint movement within a null-perpendicular-space of a Jacobian, and the null-perpendicular-space being orthogonal to a null-space of the Jacobian; calculating an avoidance movement of the plurality of joints within the null-space of the Jacobian to provide a desired clearance between the manipulator arm and a patient tissue surface; and driving the plurality of joints according to the distal portion displacing movement and the avoidance movement to provide the desired clearance between the manipulator arm and a patient tissue surface and to maintain the desired state of the distal portion.