# US 2019/0315397 A1 · Damping of an oscillation of a superimposed steering system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0315397 A1 - Document ID: US20190315397A1 - Status: Published application - Kind: A1 - Application number: 16/375,386 - Filed: 2019-04-04 - Published: 2019-10-17 - Earliest claimed: 2018-04-12 - Assignees: Audi AG - Applicants: Audi AG - Inventors: Bastian WEIGL; Andre SAAL - Web page: https://patentgrep.com/patent/US20190315397A1 ## CPC - B62D 6/06: responsive only to vehicle vibration dampening arrangements (steering dampers for cycles B62K21/08) - B62D 5/008: {Changing the transfer ratio between the steering wheel and the steering gear by variable supply of energy, e.g. by using a superposition gear} - B62D 5/0472: {for damping vibrations} - B62D 5/06: fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle - B62D 7/222: {acting on the steering wheel} - B62D: MOTOR VEHICLES; TRAILERS (steering, or guiding on a desired track, of agricultural machines or implements A01B69/00; wheels, castors, axles, increasing wheel adhesion B60B; vehicle tyres, tyre inflation or tyre changing B60C; connections between vehicles of a train or the like B60D; vehicles for use on rail and road, amphibious or convertible vehicles B60F; suspension arrangements B60G; heating, cooling, ventilating or other air treating devices B60H; windows, windscreens, non-fixed roofs, doors or similar devices, protective coverings for vehicles not in use B60J; propulsion plant arrangements, auxiliary drives, transmissions, controls, instrumentation or dashboards B60K; electric equipment or propulsion of electrically-propelled vehicles B60L; power supply for electrically-propelled vehicles B60M; passenger accommodation not otherwise provided for B60N; adaptations for load transportation or to carry special loads or objects B60P; arrangement of signalling or lighting devices, the mounting or supporting thereof or circuits therefor, for vehicles in general B60Q; vehicles, vehicle fittings or vehicle parts not otherwise provided for B60R; servicing, cleaning, repairing, supporting, lifting, or manoeuvring, not otherwise provided for, B60S; brake arrangements, brake control systems or parts thereof B60T; air-cushion vehicles B60V; motor-cycles, accessories therefor B62J, B62K; testing of vehicles G01M) ## Abstract A method for damping an oscillation of a superimposed steering system of a motor vehicle in which a sensor of the superimposed steering system detects an actual steering angle of a motor of the superimposed steering system and a control device of the superimposed steering system determines an oscillation of the superimposed steering system as a periodic change of the detected actual steering angle and, in the case of a determined oscillation, carries out a measure for damping the oscillation. ## Claims ### Claim 1 A method for damping an oscillation of a superimposed steering system of a vehicle, comprising: a sensor of the superimposed steering system detects an actual steering angle of a motor of the superimposed steering system, a control device determines an oscillation of the superimposed steering system as a periodic change of the detected actual steering angle and upon a determined oscillation it carries out a measure for reducing the oscillation, and wherein the control device carries out the measure as a function of a period number or semi-period number of the periodic change. ### Claim 2 (depends on 1) The method according to claim 1, wherein the control device counts periods or semi-periods of the periodic change and/or the control device starts the measure when the number of periods or the number of semi-periods reaches or exceeds a predetermined actuation value, and/or the control device varies the measure as a function of the counted periods or semi-periods, and/or the control device terminates the measure if it no longer determines any oscillation of the superimposed steering system and/or if at least one other exit condition has been met, and/or the control device sets a counter for counting the periods or semi-periods to zero with or after the end of the measure. ### Claim 3 (depends on 1) The method according to claim 1, in which the control device determines an oscillation if the frequency of the periodic change is in a predetermined frequency range and/or if the amplitude of the periodic change is in a predetermined amplitude range. ### Claim 4 (depends on 1) The method according to claim 1, in which the control device carries out the measure as a function of at least one other criterion met in particular for a given minimum time, in particular as a function of a traveling speed of the vehicle, of a steering wheel angle, of a steering wheel angle speed, of a control deviation of an actual steering angle from a theoretical steering angle and/or of a steering moment. ### Claim 5 (depends on 1) The method according to claim 1, wherein the control device creates a continuous transition between a phase without a measure and a phase with a measure, in particular by a filtering or a limiting of a gradient at the beginning and/or at the end of the measure. ### Claim 6 (depends on 1) The method according to claim 1, wherein the control device supplies the motor with a control current which is reduced in comparison to the normal operation of the superimposed steering system as a measure against the oscillation. ### Claim 7 (depends on 1) The method according to claim 1, wherein the control device supplies the motor with a control current opposed to the oscillation as a measure against the oscillation. ### Claim 8 A control device for a superimposed steering system of a vehicle, comprising: a sensor of the superimposed steering system detects an actual steering angle of a motor of the superimposed steering system, a control device determines an oscillation of the superimposed steering system as a periodic change of the detected actual steering angle and upon a determined oscillation it carries out a measure for reducing the oscillation, and wherein the control device carries out the measure as a function of a period number or semi-period number of the periodic change, which is configured to determine an oscillation of the superimposed steering system as a periodic change of an actual steering angle of a motor of the superimposed steering system which motor is connected to the control device, and which is configured to carry out, upon a determined oscillation as a function of a period number or semi-period number of the periodic change, a measure against the oscillation. ### Claim 9 (depends on 8) The control device according to claim 8, further comprising: a meter for counting the periods and/or semi-periods and a predetermined actuation value and is configured to start the measure when the period number or semi-period number has reached or exceeded the predetermined actuation value, and/or to vary the measure as a function of the counted periods or semi-periods, to terminate the measure when it no longer determines an oscillation and/or when at least one other exit condition has been met, and to set the meter to zero with or after the end of the measure. ### Claim 10 A superimposed steering system, comprising: a sensor of the superimposed steering system detects an actual steering angle of a motor of the superimposed steering system, a control device determines an oscillation of the superimposed steering system as a periodic change of the detected actual steering angle and upon a determined oscillation it carries out a measure for reducing the oscillation, and wherein the control device carries out the measure as a function of a period number or semi-period number of the periodic change a control device, a motor connected to the control device and comprises a sensor connected to the control device for detecting an actual steering angle of the motor, in which the control device is configured to determine an oscillation of the superimposed steering system as a periodic change of the actual steering angle detected by the sensor and, if an oscillation is determined as a function of a period number or of a semi-period number of the periodic change, to carry out a measure against the oscillation.