# US 11,999,049 B2 · Tactile feedback of an end effector of a robot manipulator over different orientation ranges > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,999,049 B2 - Document ID: US11999049B2 - Status: Granted - Kind: B2 - Application number: 17/624,013 - Filed: 2020-07-03 - Published: 2022-11-03 - Granted: 2024-06-04 - Earliest claimed: 2019-07-05 - Assignees: Franka Emika GmbH - Applicants: Franka Emika GmbH - Inventors: Andreas Spenninger - Web page: https://patentgrep.com/patent/US11999049B2 ## CPC - B25J 9/1633: {compliant, force, torque control, e.g. combined with position control} - B25J 13/025: {comprising haptic means} - B25J 9/0081: {with leader teach-in means} - B25J 9/1638: {compensation for arm bending/inertia, pay load weight/inertia} - G05B 19/42: Recording and playback systems, i.e. in which the program is recorded from a cycle of operations, e.g. the cycle of operations being manually controlled, after which this record is played back on the same machine - 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 A method includes: controlling actuators of a robot manipulator to compensate for influence of gravity; during a manual guidance of the robot manipulator detecting an orientation of an end effector; and controlling at least part of the actuators in such a way that during manual guidance of the end effector, the end effector: within a first range of a first rotation, opposes no or a speed-dependent resistance and outside the first range opposes a rotation angle-dependent resistance to the manual guidance, wherein the first rotation is a rotation angle of the end effector about its longitudinal axis; and within a second range of the second rotation, opposes no or a speed-dependent resistance to the manual guidance, and outside the second range, opposes a deflection-dependent resistance to the manual guidance, wherein the second rotation is a rotational deflection of the end effector from its original longitudinal axis or a vertical axis. ## Claims ### Claim 1 A method of controlling a robot manipulator during manual guidance of the robot manipulator by a user, wherein the robot manipulator comprises a plurality of members interconnected by joints and an end effector connected to a distal member by a further joint, and wherein actuators are arranged at all joints, the method comprising: controlling the actuators to compensate for a gravitational force acting on the robot manipulator by a control unit, so that the robot manipulator, starting from a stationary pose, remains in the stationary pose without acceleration without application of external force, but that the robot manipulator is guidable manually; during the manual guidance of the robot manipulator by the user: detecting an orientation of the end effector with respect to the distal member or with respect to an earth-fixed coordinate system by an angle detecting unit; and controlling at least part of the actuators of the robot manipulator by the control unit based on the orientation of the end effector detected by the angle detection unit in such a way that, during the manual guidance of the end effector, the end effector: within a first range of a first rotation of the end effector, experiences damping by a speed-dependent resistance to the manual guidance, and outside the first range, experiences springing by a rotation angle-dependent resistance to the manual guidance, wherein the first rotation is a rotation angle of the end effector about a longitudinal axis of the end effector, and within a second range of a second rotation of the end effector, experiences damping by the speed-dependent resistance to the manual guidance, and outside the second range, experiences springing by a deflection-dependent resistance to the manual guidance, wherein the second rotation is a rotational deflection of the end effector from its originally aligned longitudinal axis or a vertical axis of the earth-fixed coordinate system. ### Claim 2 (depends on 1) The method according to claim 1, wherein the second rotation is a rotational deflection of the end effector from an original longitudinal axis or the vertical axis in a predetermined plane. ### Claim 3 (depends on 2) The method according to claim 2, wherein the predetermined plane is a vertical plane and the second rotation is defined about a horizontal axis of the earth-fixed coordinate system wherein the horizontal axis maintains its orientation with respect to an earth-fixed environment of the robot manipulator even when the robot manipulator is rotated about the vertical axis. ### Claim 4 (depends on 1) The method according to claim 1, wherein the second rotation is a rotational deflection of the end effector from an original longitudinal axis or the vertical axis in deflection directions having a common center of rotation. ### Claim 5 (depends on 1) The method according to claim 1, wherein controlling the at least part of the actuators of the robot manipulator takes place in such a way that, during the manual guidance of the end effector, the end effector outside the first range and/or outside the second range additionally experiences damping by the speed-dependent resistance to the manual guidance. ### Claim 6 (depends on 1) The method according to claim 1, wherein the deflection-dependent resistance outside the second range is nonlinear to the rotational deflection and/or the rotation angle-dependent resistance outside the first range is nonlinear to the rotation angle. ### Claim 7 (depends on 6) The method according to claim 6, wherein a respective nonlinear function between rotational deflection and resistance and/or between rotation angle and resistance is one of the following: sigmoid function; polynomial function; trigonometric function; exponential function; and logarithmic function. ### Claim 8 (depends on 1) The method according to claim 1, wherein each of the deflection-dependent resistance and/or each of the rotation angle-dependent resistance saturates at a predetermined upper limit. ### Claim 9 (depends on 1) The method according to claim 1, wherein controlling the at least part of the actuators of the robot manipulator by the control unit takes place in such a way that during the manual guidance of the end effector, the end effector within the second range of the second rotation additionally experiences springing by the deflection-dependent resistance to the manual guidance, wherein the deflection-dependent resistance within the second range is smaller than half the deflection-dependent resistance outside the second range per deflection. ### Claim 10 A robot manipulator controllable during manual guidance by a user, wherein the robot manipulator comprises a plurality of members interconnected by joints and an end effector connected to a distal member by a further joint, and wherein actuators are arranged at all joints, the robot manipulator further comprising: an angle detection unit configured to detect an orientation of the end effector with respect to the distal member or with respect to an earth-fixed coordinate system during the manual guidance of the robot manipulator by the user, and a control unit configured to control the actuators to compensate for a gravitational force acting on the robot manipulator such that the robot manipulator, starting from a stationary pose, remains in the stationary pose without acceleration without the application of external force, but that the robot manipulator is guidable manually, the control unit further configured to control at least part of the actuators of the robot manipulator, during the manual guidance of the robot manipulator by the user, based on the orientation of the end effector detected by the angle detection unit in such a way that during the manual guidance of the end effector, the end effector: within a first range of a first rotation of the end effector, experiences damping by a speed-dependent resistance to the manual guidance, and outside the first range, experiences springing by a rotation angle-dependent resistance to the manual guidance, wherein the first rotation is a rotation angle of the end effector about a longitudinal axis of the end effector, and within a second range of a second rotation of the end effector, experiences damping by the speed-dependent resistance to the manual guidance, and outside the second range, experiences springing by a deflection-dependent resistance to the manual guidance, wherein the second rotation is a rotational deflection of the end effector from its originally aligned longitudinal axis or a vertical axis of the earth-fixed coordinate system. ### Claim 11 (depends on 10) The robot manipulator according to claim 10, wherein the second rotation is a rotational deflection of the end effector from an original longitudinal axis or the vertical axis in a predetermined plane. ### Claim 12 (depends on 11) The robot manipulator according to claim 11, wherein the predetermined plane is a vertical plane and the second rotation is defined about a horizontal axis of the earth-fixed coordinate system, wherein the horizontal axis maintains its orientation with respect to an earth-fixed environment of the robot manipulator even when the robot manipulator is rotated about the vertical axis. ### Claim 13 (depends on 10) The robot manipulator according to claim 10, wherein the second rotation is a rotational deflection of the end effector from an original longitudinal axis or the vertical axis in deflection directions having a common center of rotation. ### Claim 14 (depends on 10) The robot manipulator according to claim 10, wherein control of the at least part of the actuators of the robot manipulator takes place in such a way that, during the manual guidance of the end effector, the end effector outside the first range and/or outside the second range additionally experiences damping by the speed-dependent resistance to the manual guidance. ### Claim 15 (depends on 10) The robot manipulator according to claim 10, wherein the deflection-dependent resistance outside the second range is nonlinear to the rotational deflection and/or the rotation angle-dependent resistance outside the first range is nonlinear to the rotation angle. ### Claim 16 (depends on 15) The robot manipulator according to claim 15, wherein a respective nonlinear function between rotational deflection and resistance and/or between rotation angle and resistance is one of the following: sigmoid function; polynomial function; trigonometric function; exponential function; and logarithmic function. ### Claim 17 (depends on 10) The robot manipulator according to claim 10, wherein each of each of the deflection-dependent resistance and/or each of the rotation angle-dependent resistance saturates at a predetermined upper limit. ### Claim 18 (depends on 10) The robot manipulator according to claim 10, wherein control of the at least part of the actuators of the robot manipulator by the control unit takes place in such a way that during the manual guidance of the end effector, the end effector within the second range of the second rotation additionally experiences springing by the deflection-dependent resistance to the manual guidance, wherein the deflection-dependent resistance within the second range is smaller than half the deflection-dependent resistance outside the second range per deflection.