# US 12,222,265 B1 · Systems and methods for actuator backlash measurement and monitoring > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,222,265 B1 - Document ID: US12222265B1 - Status: Granted - Kind: B1 - Application number: 18/825,203 - Filed: 2024-09-05 - Granted: 2025-02-11 - Earliest claimed: 2024-03-29 - Assignees: Archer Aviation Inc. - Applicants: Archer Aviation Inc. - Inventors: Kurt James Wagner - Web page: https://patentgrep.com/patent/US12222265B1 ## CPC - G01M 13/02: Gearings; Transmission mechanisms - G01M 99/008: {by doing functionality tests} - B64D 43/00: Arrangements or adaptations of instruments - B64D 45/0005: {Devices specially adapted to indicate the position of a movable element of the aircraft, e.g. landing gear} - B64F 5/60: Testing or inspecting aircraft components or systems - F16H 57/01: Monitoring wear or stress of gearing elements, e.g. for triggering maintenance - B64C 29/0033: {the propellers being tiltable relative to the fuselage} - B64D 27/34: All-electric aircraft - B64D 2045/0085: {Devices for aircraft health monitoring, e.g. monitoring flutter or vibration} - F16H 2057/012: {of gearings} - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - B64F: GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR - F16H: GEARING - B64C: AEROPLANES; HELICOPTERS ## Abstract Systems and methods for backlash measurement and monitoring are disclosed for an actuator having a motor end and an output end. The method may include: driving the motor end of the actuator to one endpoint; measuring, using a first sensor, a motor-end initial position value associated with the motor end; measuring, using a second sensor, an output-end initial position value associated with the output end; driving the motor end of the actuator to another endpoint; measuring a motor-end final position value using the first sensor and an output-end final position value using the second sensor; determining a backlash value based on the motor-end initial position value, output-end initial position value, motor-end final position value, and output-end final position value; generating a signal based on comparing the backlash value to a predetermined threshold; and displaying a notification indicative of an operational condition of the actuator based on the signal. ## Claims ### Claim 1 A method for backlash measurement of an actuator for an aircraft, the actuator comprising a motor end and an output end, the method comprising: driving the motor end of the actuator to one endpoint; measuring, using a sensor, an output-end initial position value associated with the output end of the actuator; determining a first difference between the output-end initial position value and a motor-end initial position value, the motor-end initial position value being associated with the motor end of the actuator; driving the motor end of the actuator to another endpoint; determining, using the sensor or another sensor, an output-end final position value associated with the output end of the actuator; determining a second difference between the output-end final position value and a motor-end final position value, the motor-end final position value being associated with the motor end of the actuator; determining a backlash value of the actuator by combining the first difference and the second difference; generating a comparison of the backlash value and at least one predetermined threshold; generating a signal based on the comparison; and displaying, on a display device, a notification indicative of an operational condition of the actuator based on the signal. ### Claim 2 (depends on 1) The method of claim 1, wherein combining the first difference and the second difference includes adding the first difference and the second difference. ### Claim 3 (depends on 1) The method of claim 1, wherein the sensor is an output-end sensor and the method further includes determining the motor-end initial position value and the motor-end final position value using a motor-end sensor. ### Claim 4 (depends on 3) The method of claim 3, wherein the output-end sensor is operatively connected to one end of a gear train of the actuator and the motor-end sensor is operatively connected to another end of the gear train of the actuator. ### Claim 5 (depends on 3) The method of claim 3, wherein the output-end sensor is operatively connected to one end of a screw of the actuator and the motor-end sensor is operatively connected to another end of the screw of the actuator. ### Claim 6 (depends on 1) The method of claim 1, wherein the at least one predetermined threshold comprises: a first predetermined threshold; and a second predetermined threshold greater than the first predetermined threshold. ### Claim 7 (depends on 6) The method of claim 6, wherein the first predetermined threshold is associated with the operational condition indicating that the actuator is acceptable for use. ### Claim 8 (depends on 7) The method of claim 7, wherein the second predetermined threshold is associated with the operational condition indicating that the actuator is not acceptable for use. ### Claim 9 (depends on 6) The method of claim 6, wherein the at least one predetermined threshold is determined based on at least one of historical data or model simulation. ### Claim 10 (depends on 1) The method of claim 1, wherein the signal includes a command to prevent the aircraft from taking off or flying. ### Claim 11 (depends on 1) The method of claim 1, further comprising backlash monitoring of the actuator. ### Claim 12 A system for backlash measurement of an actuator for an aircraft, the actuator comprising a motor end and an output end, the system comprising: a first sensor associated with the output end; a second sensor associated with the motor end; at least one processor; and at least one non-transitory computer-readable medium containing instructions that, when executed by the at least one processor, causes the at least one processor to perform operations comprising: driving the motor end of the actuator to one endpoint; determining, based on the first sensor and the second sensor, a first difference between an output-end initial position and a motor-end initial position; determining a second difference between an output-end final position and a motor-end final position, wherein the output-end initial position and the output-end final position are associated with the output end of the actuator, and the motor-end initial position and the motor-end final position are associated with the motor end of the actuator; determining a backlash value of the actuator by combining the first difference and the second difference; generating a comparison of the backlash value and at least one predetermined threshold; generating a signal based on the comparison; and displaying, on a display device, a notification indicative of an operational condition of the actuator based on the signal. ### Claim 13 (depends on 12) The system of claim 12, wherein the first sensor is operatively connected to one end of a gear train of the actuator and the second sensor is operatively connected to another end of the gear train of the actuator. ### Claim 14 (depends on 12) The system of claim 12, wherein the first sensor is operatively connected to one end of a screw of the actuator and the second sensor is operatively connected to another end of the screw of the actuator. ### Claim 15 (depends on 12) The system of claim 12, wherein the at least one predetermined threshold comprises: a first predetermined threshold; and a second predetermined threshold greater than the first predetermined threshold. ### Claim 16 (depends on 15) The system of claim 15, wherein the first predetermined threshold is associated with the operational condition indicating that the actuator is acceptable for use. ### Claim 17 (depends on 16) The system of claim 16, wherein the second predetermined threshold is associated with the operational condition indicating that the actuator is not acceptable for use. ### Claim 18 (depends on 12) The system of claim 12, wherein the at least one predetermined threshold is determined based on at least one of historical data or model simulation. ### Claim 19 (depends on 12) The system of claim 12, wherein the signal includes a command to prevent the aircraft from taking off or flying. ### Claim 20 A method for backlash measurement of an actuator, the actuator comprising a motor end and an output end, comprising: driving the motor end of the actuator to one endpoint; determining a first difference between an output-end initial position and a motor-end initial position, the output-end initial position being associated with the output end of the actuator and the motor-end initial position being associated with the motor end of the actuator; driving the motor end of the actuator to another endpoint; determining a second difference between an output-end final position and a motor-end final position, the output-end final position being associated with the output end of the actuator and the motor-end final position being associated with the motor end of the actuator; determining a backlash value of the actuator based on the first difference and the second difference; generating a comparison of the backlash value and at least one predetermined threshold; generating a signal based on the comparison; and displaying, on a display device, a notification indicative of an operational condition of the actuator based on the signal. ### Claim 21 (depends on 20) The method of claim 20, further comprising determining the output-end initial position and the output-end final position using a first sensor associated with the output end. ### Claim 22 (depends on 21) The method of claim 21, further comprising determining the motor-end initial position and the motor-end final position using a second sensor associated with the motor end. ### Claim 23 (depends on 22) The method of claim 22, wherein the first sensor is operatively connected to one end of a gear train of the actuator and the second sensor is operatively connected to another end of the gear train of the actuator. ### Claim 24 (depends on 22) The method of claim 22, wherein the first sensor is operatively connected to one end of a screw of the actuator and the second sensor is operatively connected to another end of the screw of the actuator. ### Claim 25 (depends on 20) The method of claim 20, wherein the at least one predetermined threshold comprises: a first predetermined threshold; and a second predetermined threshold greater than the first predetermined threshold. ### Claim 26 (depends on 25) The method of claim 25, wherein the first predetermined threshold is associated with the operational condition indicating that the actuator is acceptable for use. ### Claim 27 (depends on 25) The method of claim 25, wherein the second predetermined threshold is associated with the operational condition indicating that the actuator is not acceptable for use. ### Claim 28 (depends on 20) The method of claim 20, wherein the at least one predetermined threshold is determined based on at least one of historical data or model simulation. ### Claim 29 (depends on 20) The method of claim 20, wherein determining the backlash value includes adding the first difference and the second difference. ### Claim 30 (depends on 20) The method of claim 20, further comprising backlash monitoring of the actuator.