# US 12,004,817 B2 · Method and apparatus for controlling a haptic device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,004,817 B2 - Document ID: US12004817B2 - Status: Granted - Kind: B2 - Application number: 17/150,370 - Filed: 2021-01-15 - Published: 2021-05-06 - Granted: 2024-06-11 - Earliest claimed: 2006-05-19 - Assignees: MAKO Surgical Corp. - Applicants: MAKO Surgical Corp. - Inventors: Hyosig Kang; Dennis Moses; Arthur Quaid - Web page: https://patentgrep.com/patent/US12004817B2 ## CPC - A61B 34/20: Surgical navigation systems; Devices for tracking or guiding surgical instruments, e.g. for frameless stereotaxis - A61B 17/1764: {for the knee} - A61B 34/10: Computer-aided planning, simulation or modelling of surgical operations - A61B 34/30: Surgical robots - A61B 34/71: {Manipulators operated by drive cable mechanisms} - A61B 34/76: {Manipulators having means for providing feel, e.g. force or tactile feedback} - A61B 90/03: {Automatic limiting or abutting means, e.g. for safety} - G16H 40/40: for the management of medical equipment or devices, e.g. scheduling maintenance or upgrades - A61B 34/25: {User interfaces for surgical systems} - A61B 2017/00119: {alarm; indicating an abnormal situation} - A61B 2017/00694: {with means correcting for movement of or for synchronisation with the body} - A61B 2017/00712: {simulating mathematical properties, e.g. for testing of positioning in the isocentre or focus} - A61B 2017/00725: {Calibration or performance testing} - A61B 2034/102: {Modelling of surgical devices, implants or prosthesis} - A61B 2034/107: {Visualisation of planned trajectories or target regions} - A61B 2034/108: {Computer aided selection or customisation of medical implants or cutting guides} - A61B 2034/2055: {Optical tracking systems} - A61B 2034/2059: {Mechanical position encoders} - A61B 2034/2065: {Tracking using image or pattern recognition} - A61B 2034/2068: {using pointers, e.g. pointers having reference marks for determining coordinates of body points} - A61B 2034/207: {Divots for calibration} - A61B 2034/2072: {Reference field transducer attached to an instrument or patient} - A61B 2034/305: {Details of wrist mechanisms at distal ends of robotic arms} - A61B 2090/363: {Use of fiducial points} - A61B 2090/364: {Correlation of different images or relation of image positions in respect to the body} - A61B 2090/3983: {Reference marker arrangements for use with image guided surgery} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - G16H: HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA ## Abstract A method of operating a robotic surgical system includes monitoring a force applied at a surgical instrument attached to a robotic arm, comparing the force to a force threshold for a surgical procedure, providing a signal in response to the force being outside the force threshold, monitoring, using a reference array attached to a patient, a bone movement caused while the surgical instrument interacts with the patient, and adjusting control of the robotic arm based on the bone movement. ## Claims ### Claim 1 A method of operating a robotic surgical system comprising a robotic arm, comprising: monitoring, using a reference array attached to a patient, a bone movement caused while a surgical instrument interacts with the patient; adjusting control of the robotic arm based on the bone movement; and detecting a fault condition associated with operation of the robotic surgical system; in response to the fault condition, changing the control of the robotic arm to a free mode in which the robotic arm is freely movable by a user while the robotic arm operates to counteract gravitational loads on the robotic arm. ### Claim 2 (depends on 1) The method of claim 1, wherein adjusting control of the robotic arm comprises causing the surgical instrument to follow the bone movement. ### Claim 3 (depends on 1) The method of claim 1, comprising generating a fault signal in response to the fault condition, wherein the fault condition relates to violation of a force threshold or velocity threshold. ### Claim 4 (depends on 1) The method of claim 1, wherein the method further comprises shutting off power to a surgical instrument coupled to the robotic arm in response to the fault condition such that power to the surgical instrument is off while the robotic arm operates in the free mode. ### Claim 5 (depends on 4) The method of claim 4, wherein the surgical instrument comprises a cutting tip. ### Claim 6 (depends on 1) The method of claim 1, wherein changing the control of the robotic arm to the free mode comprises changing the control of the robotic arm from a haptic mode in which a force is exerted by the robotic arm based on a virtual object. ### Claim 7 (depends on 6) The method of claim 6, further comprising generating, by the robotic arm, the force to constrain a surgical instrument to the virtual object. ### Claim 8 (depends on 7) The method of claim 7, further comprising controlling the robotic arm comprising preventing the robotic arm from generating an excessively high force. ### Claim 9 (depends on 1) The method of claim 1, wherein detecting the fault condition comprises detecting occlusion of an optical tracking system. ### Claim 10 A surgical robot system comprising: a robot base; a robotic arm connected to the robot base and having a distal end opposite the robot base; a tracking system configured to monitor movement of at least one of a first marker configured to be coupled to a patient and a second marker configured to be coupled to the robot base; and a controller programmed to switch control of the robotic arm into a free mode responsive to detecting a fault condition, wherein detecting the fault condition is based on a threshold being exceeded by one of a force at the robotic arm, a change in position of the first marker, or a change in position of the second marker; wherein the controller is programmed to control the robotic arm in the free mode by causing the robotic arm to counteract gravitational loads on the robotic arm while enabling the robotic arm to be freely moved by a user. ### Claim 11 (depends on 10) The surgical robot system of claim 10, further comprising a display device configured to display a warning message. ### Claim 12 (depends on 10) The surgical robot system of claim 10, further comprising a surgical instrument configured for cutting into a bone, wherein the first marker is configured to be coupled to the bone, and wherein the fault condition is detected responsive to the change in position of the first marker exceeding the threshold. ### Claim 13 (depends on 10) The surgical robot system of claim 10, the robotic arm comprising one or more sensors configured to provide data indicative of a position of the distal end relative to the robot base, wherein detecting the fault condition comprises determining that the change in position of the second marker violates the threshold. ### Claim 14 (depends on 10) The surgical robot system of claim 10, further comprising an electrical surgical instrument, the system configured such that the electrical surgical instrument turns off responsive to the fault condition. ### Claim 15 A computer-implemented method for computer-aided surgery, comprising: monitoring a force experienced at an electric tool attached to a robotic arm; shutting off power to the electric tool in response to the force being outside a force threshold and adjusting control of the robotic arm in response to the force being outside the force threshold by switching control of the robotic arm from a haptic mode to a free mode, wherein placing the robotic arm in the free mode comprises operating the robotic arm to counteract gravitational loads on the robotic arm while allowing a user to freely move the robotic arm without constraint by a haptic object used in the haptic mode; monitoring, using a reference array attachable to a patient, a bone movement caused while the electric tool interacts with the patient; and adjusting control of the robotic arm based on the bone movement. ### Claim 16 (depends on 15) The computer-implemented method of claim 15, wherein adjusting control of the robotic arm comprises causing the electric tool to follow the bone movement. ### Claim 17 (depends on 15) The computer-implemented method of claim 15, wherein shutting off power to the surgical tool cause a blade of the surgical tool to stop moving relative to a remainder of the surgical tool. ### Claim 18 (depends on 15) The computer-implemented method of claim 15, the operations further comprising preventing the robotic arm from generating an excessively high force.