# US 9,675,421 B2 · Systems and methods for cancellation of joint motion using the null-space > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,675,421 B2 - Document ID: US9675421B2 - Status: Granted - Kind: B2 - Application number: 14/802,866 - Filed: 2015-07-17 - Published: 2016-02-18 - Granted: 2017-06-13 - Earliest claimed: 2012-08-15 - Assignees: Intuitive Surgical Operations, Inc. - Applicants: Intuitive Surgical Operations, Inc. - Inventors: Arjang M. Hourtash; Pushkar Hingwe - Web page: https://patentgrep.com/patent/US9675421B2 ## CPC - A61B 34/30: Surgical robots - A61B 34/35: for telesurgery - A61B 34/37: Leader-follower robots (A61B34/35 takes precedence) - B25J 9/1643: {redundant control} - A61B 34/32: operating autonomously - A61B 2034/306: {Wrists with multiple vertebrae} - B25J 9/1607: {Calculation of inertia, jacobian matrixes and inverses} - G05B 2219/40362: Elbow high or low, avoid obstacle collision with redundancy control - G05B 2219/40365: Configuration control, select other tasks by configuration of link positions - G05B 2219/40367: Redundant manipulator - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract Devices, systems, and methods are disclosed for cancelling movement of one or more joints of a telesurgical manipulator to effect manipulation movement of an end effector. Methods include calculating movement of joints within a null-perpendicular space to effect desired end effector movement while calculating movement of one or more locked joints within a null-space to cancel the movement of the locked joints within the null-perpendicular-space. Methods may further include calculating movement of one or more joints to effect an auxiliary movement or a reconfiguration movement that may include movement of one or more locked joints. The auxiliary and reconfiguration movements may overlay the manipulation movement of the joints to allow movement of the locked joints to effect the auxiliary movement or reconfiguration movement, while the movement of the locked joints to effect manipulation is canceled. Various configurations for devices and systems utilizing such methods are provided herein. ## Claims ### Claim 1 A method comprising: receiving a command to move an end effector of a manipulator arm in an end-effector displacement, the manipulator arm including a proximal portion coupled to a base, a distal portion including the end effector, and a plurality of joints between the distal portion and the base, the plurality of joints being operable to allow a range of differing states of the plurality of joints for a given state of the distal portion; designating one or more non-moving joints of the plurality of joints; determining an end-effector-displacing movement of the plurality of joints to effect the end-effector displacement; determining a cancellation movement of the plurality of joints, the cancellation movement corresponding to a non-moving end effector, and the cancellation movement providing a cancellation of joint movement for each of the one or more non-moving joints when the cancellation movement is combined with the end-effector displacing movement; and driving the plurality of joints by combining the end-effector-displacing movement and the cancellation movement to effect the end-effector displacement. ### Claim 2 (depends on 1) The method of claim 1, wherein for each joint of the one or more non-moving joints, the corresponding joint velocities for the end-effector-displacing movement and the cancellation movement combine to effect the cancellation of joint movement for that joint. ### Claim 3 (depends on 1) The method of claim 1, further comprising: calculating values for the cancellation movement so that, for each of the one or more non-moving joints, a corresponding joint velocity for the cancellation movement cancels a corresponding joint velocity for the end-effector-displacing movement. ### Claim 4 (depends on 1) The method of claim 1, wherein determining the end-effector-displacing movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a moving end effector; and determining the cancellation movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a non-moving end effector. ### Claim 5 (depends on 1) The method of claim 1, further comprising: calculating a matrix that relates joint velocities of the plurality of joints to motions of the end effector, the matrix including a plurality of joint-velocity directions corresponding to a moving end-effector and one or more joint-velocity directions corresponding to a non-moving end effector; determining the end-effector-displacing movement of the plurality of joints from a calculation based on the plurality of joint-velocity directions corresponding to a moving end-effector; and determining the cancellation movement of the plurality of joints from a calculation based on the one or more joint-velocity directions corresponding to a non-moving end-effector. ### Claim 6 (depends on 1) The method of claim 1, wherein determining the end-effector-displacing movement of the plurality of joints includes calculating joint velocities of the plurality of joints within a null-perpendicular space of a Jacobian matrix for the plurality of joints; and determining the cancellation movement of the plurality of joints includes calculating joint velocities of the plurality of joints within a null space of the Jacobian, the null space being orthogonal to the null-perpendicular space. ### Claim 7 (depends on 1) The method of claim 1, further comprising: determining an auxiliary movement of a first joint set of the plurality of joints, the first joint set being selected from the one or more non-moving joints of the plurality of joints, and the auxiliary movement being determined from directions that correspond to a non-moving end effector; and driving the plurality of joints by combining the auxiliary movement with the end-effector-displacing movement and the cancellation movement to effect a goal of the auxiliary movement, the goal of the auxiliary movement including a desired pose, a desired configuration, or a collision avoidance for the manipulator arm. ### Claim 8 A system comprising: a manipulator arm including a proximal portion coupled to a base, a distal portion including an end effector, and a plurality of joints between the distal portion and the base, the plurality of joints being operable to allow a range of differing states of the plurality of joints for a given state of the distal portion; and a motion unit including one or more processors configured to perform operations including: receiving a command to move the end effector of the manipulator arm in an end-effector displacement; designating one or more non-moving joints of the plurality of joints; determining an end-effector-displacing movement of the plurality of joints to effect the end-effector displacement; determining a cancellation movement of the plurality of joints, the cancellation movement corresponding to a non-moving end effector, and the cancellation movement providing a cancellation of joint movement for each of the one or more non-moving joints when the cancellation movement is combined with the end-effector displacing movement; and driving the plurality of joints by combining the end-effector-displacing movement and the cancellation movement to effect the end-effector displacement. ### Claim 9 (depends on 8) The system of claim 8, wherein for each joint of the one or more non-moving joints, the corresponding joint velocities for the end-effector-displacing movement and the cancellation movement combine to effect the cancellation of joint movement for that joint. ### Claim 10 (depends on 8) The system of claim 8, wherein the one or more processors are further configured to perform operations including: calculating values for the cancellation movement so that, for each of the one or more non-moving joints, a corresponding joint velocity for the cancellation movement cancels a corresponding joint velocity for the end-effector-displacing movement. ### Claim 11 (depends on 8) The system of claim 8, wherein determining the end-effector-displacing movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a moving end effector; and determining the cancellation movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a non-moving end effector. ### Claim 12 (depends on 8) The system of claim 8, wherein the one or more processors are further configured to perform operations including: calculating a matrix that relates joint velocities of the plurality of joints to motions of the end effector, the matrix including a plurality of joint-velocity directions corresponding to a moving end-effector and one or more joint-velocity directions corresponding to a non-moving end effector; determining the end-effector-displacing movement of the plurality of joints from a calculation based on the plurality of joint-velocity directions corresponding to a moving end-effector; and determining the cancellation movement of the plurality of joints from a calculation based on the one or more joint-velocity directions corresponding to a non-moving end-effector. ### Claim 13 (depends on 8) The system of claim 8, wherein determining the end-effector-displacing movement of the plurality of joints includes calculating joint velocities of the plurality of joints within a null-perpendicular space of a Jacobian matrix for the plurality of joints; and determining the cancellation movement of the plurality of joints includes calculating joint velocities of the plurality of joints within a null space of the Jacobian, the null space being orthogonal to the null-perpendicular space. ### Claim 14 (depends on 8) The system of claim 8, wherein the one or more processors are further configured to perform operations including: determining an auxiliary movement of a first joint set of the plurality of joints, the first joint set being selected from the one or more non-moving joints of the plurality of joints, and the auxiliary movement being determined from directions that correspond to a non-moving end effector; and driving the plurality of joints by combining the auxiliary movement with the end-effector-displacing movement and the cancellation movement to effect a goal of the auxiliary movement, the goal of the auxiliary movement including a desired pose, a desired configuration, or a collision avoidance for the manipulator arm. ### Claim 15 A memory device including instructions that, when executed by one or more processors, cause the one or more processors to perform operations comprising: receiving a command to move an end effector of a manipulator arm in an end-effector displacement, the manipulator arm including a proximal portion coupled to a base, a distal portion including the end effector, and a plurality of joints between the distal portion and the base, the plurality of joints being operable to allow a range of differing states of the plurality of joints for a given state of the distal portion; designating one or more non-moving joints of the plurality of joints; determining an end-effector-displacing movement of the plurality of joints to effect the end-effector displacement; determining a cancellation movement of the plurality of joints, the cancellation movement corresponding to a non-moving end effector, and the cancellation movement providing a cancellation of joint movement for each of the one or more non-moving joints when the cancellation movement is combined with the end-effector displacing movement; and driving the plurality of joints by combining the end-effector-displacing movement and the cancellation movement to effect the end-effector displacement. ### Claim 16 (depends on 15) The memory device of claim 15, wherein for each joint of the one or more non-moving joints, the corresponding joint velocities for the end-effector-displacing movement and the cancellation movement combine to effect the cancellation of joint movement for that joint. ### Claim 17 (depends on 15) The memory device of claim 15, wherein the memory device further includes instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: calculating values for the cancellation movement so that, for each of the one or more non-moving joints, a corresponding joint velocity for the cancellation movement cancels a corresponding joint velocity for the end-effector-displacing movement. ### Claim 18 (depends on 15) The memory device of claim 15, wherein determining the end-effector-displacing movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a moving end effector; and determining the cancellation movement of the plurality of joints includes calculating joint velocities of the plurality of joints from directions that correspond to a non-moving end effector. ### Claim 19 (depends on 15) The memory device of claim 15, wherein the memory device further includes instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: calculating a matrix that relates joint velocities of the plurality of joints to motions of the end effector, the matrix including a plurality of joint-velocity directions corresponding to a moving end-effector and one or more joint-velocity directions corresponding to a non-moving end effector; determining the end-effector-displacing movement of the plurality of joints from a calculation based on the plurality of joint-velocity directions corresponding to a moving end-effector; and determining the cancellation movement of the plurality of joints from a calculation based on the one or more joint-velocity directions corresponding to a non-moving end-effector. ### Claim 20 (depends on 15) The memory device of claim 15, wherein the memory device further includes instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: determining an auxiliary movement of a first joint set of the plurality of joints, the first joint set being selected from the one or more non-moving joints of the plurality of joints, and the auxiliary movement being determined from directions that correspond to a non-moving end effector; and driving the plurality of joints by combining the auxiliary movement with the end-effector-displacing movement and the cancellation movement to effect a goal of the auxiliary movement, the goal of the auxiliary movement including a desired pose, a desired configuration, or a collision avoidance for the manipulator arm.