# US 11,897,560 B2 · Road surface impact stimulation device of steer-by-wire system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,897,560 B2 - Document ID: US11897560B2 - Status: Granted - Kind: B2 - Application number: 17/617,924 - Filed: 2020-06-04 - Published: 2022-09-29 - Granted: 2024-02-13 - Earliest claimed: 2019-06-10 - Assignees: Hl Mando Corporation - Applicants: Hl Mando Corporation - Inventors: Seung Gi Min - Web page: https://patentgrep.com/patent/US11897560B2 ## CPC - B62D 6/008: {Control of feed-back to the steering input member, e.g. simulating road feel in steer-by-wire applications} - B60W 10/20: including control of steering systems - B62D 5/0481: {monitoring the steering system, e.g. failures} - B62D 6/007: {adjustable by the driver, e.g. sport mode} - 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) - B60W: CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT ## Abstract The present disclosure provides a road impact simulating apparatus of a steer-by-wire system, the apparatus comprising: a Signal processor for determining a wheel speed difference value between wheels, and determining a lateral acceleration difference value between an estimated lateral acceleration and a sensed lateral acceleration of a vehicle; an Impact determinator for determining whether there is a road impact based on the wheel speed difference value; and a Torque calculator for determining a reaction force torque according to the road impact based on the lateral acceleration difference value if it is determined as the road impact. ## Claims ### Claim 1 A road impact simulating apparatus of a steer-by-wire system, the apparatus comprising a controller configured to: determine a wheel speed difference value between wheels, and determine a lateral acceleration difference value between an estimated lateral acceleration of a vehicle and a sensed lateral acceleration of the vehicle; determine whether there is a road impact based on the wheel speed difference value between the wheels; and determine a reaction force torque according to the road impact based on the lateral acceleration difference value if it is determined as the road impact, wherein the controller is configured to, if a first wheel speed difference value between the left and right front wheels is greater than or equal to a first reference value, a second wheel speed difference value between the left and right rear wheels is less than or equal to a second reference value, and a third wheel speed difference value between the left front and rear wheels or a fourth wheel speed difference value between the right front and rear wheels is greater than or equal to a third reference value, determine that there is the road impact. ### Claim 2 (depends on 1) The road impact simulating apparatus of the steer-by-wire system of claim 1, further comprising a driver configured to apply the reaction force torque to a steering wheel. ### Claim 3 (depends on 1) The road impact simulating apparatus of the steer-by-wire system of claim 1, further comprising: a wheel speed sensor for detecting wheel speed of the wheel; and a lateral acceleration sensor for detecting the sensed lateral acceleration, wherein the controller is configured to determine the estimated lateral acceleration based on a steering angle and a vehicle speed. ### Claim 4 (depends on 1) The road impact simulating apparatus of the steer-by-wire system of claim 1, wherein the controller is configured to, if a first wheel speed difference value between the left and right front wheels is greater than or equal to a first reference value and a second wheel speed difference value between the left and right rear wheels is less than or equal to a second reference value, determine that there is the road impact. ### Claim 5 (depends on 4) The road impact simulating apparatus of the steer-by-wire system of claim 4, wherein the controller is configured to, if the controller determines that there is the road impact and a steering torque of a vehicle driver is less than or equal to a fourth reference value or a rack force is less than or equal to a fifth reference value, output a road impact signal. ### Claim 6 (depends on 5) The road impact simulating apparatus of the steer-by-wire system of claim 5, wherein the controller is configured to receive the road impact signal and determine an active count, which is an application time of the reaction force torque. ### Claim 7 (depends on 6) The road impact simulating apparatus of the steer-by-wire system of claim 6, wherein the controller is configured to determine the active count based on a wheelbase and a vehicle speed of the vehicle. ### Claim 8 (depends on 1) The road impact simulating apparatus of the steer-by-wire system of claim 1, wherein the controller is configured to set a reaction force torque map that defines the reaction force torque according to a difference in lateral acceleration for each vehicle speed, and determine the reaction force torque according to the lateral acceleration difference value and the vehicle speed using the reaction force torque map. ### Claim 9 A road impact simulating method of a steer-by-wire system, the method comprising: determining a wheel speed difference value between wheels, and determining a lateral acceleration difference value between an estimated lateral acceleration of a vehicle and a sensed lateral acceleration of the vehicle; determining whether there is a road impact based on the wheel speed difference value; determining a reaction force torque according to the road impact based on the lateral acceleration difference value if it is determined that there is the road impact; and if a first wheel speed difference value between the left and right front wheels is greater than or equal to a first reference value, a second wheel speed difference value between the left and right rear wheels is less than or equal to a second reference value, and a third wheel speed difference value between the left front and rear wheels or a fourth wheel speed difference value between the right front and rear wheels is greater than or equal to a third reference value, determining that there is the road impact. ### Claim 10 (depends on 9) The road impact simulating method of the steer-by-wire system of claim 9, further comprising applying the reaction force torque to a steering wheel. ### Claim 11 (depends on 10) The road impact simulating method of the steer-by-wire system of claim 10, further comprising: detecting wheel speed of the wheel; detecting the sensed lateral acceleration; and determining the estimated lateral acceleration based on a steering angle and a vehicle speed. ### Claim 12 (depends on 9) The road impact simulating method of the steer-by-wire system of claim 9, further comprising, if a first wheel speed difference value between the left and right front wheels is greater than or equal to a first reference value and a second wheel speed difference value between the left and right rear wheels is less than or equal to a second reference value, determining that there is the road impact. ### Claim 13 (depends on 12) The road impact simulating method of the steer-by-wire system of claim 12, wherein further comprising, if it is determined that there is the road impact and a steering torque of a vehicle driver is less than or equal to a fourth reference value or a rack force is less than or equal to a fifth reference value, outputting a road impact signal. ### Claim 14 (depends on 13) The road impact simulating method of the steer-by-wire system of claim 13, further comprising receiving the road impact, signal and determine an active count, which is an application time of the reaction force torque. ### Claim 15 (depends on 14) The road impact simulating method of the steer-by-wire system of claim 14, further comprising determining the active count based on a wheelbase and a vehicle speed of the vehicle. ### Claim 16 (depends on 9) The road impact simulating method of the steer-by-wire system of claim 9, further comprising setting a reaction force torque map that defines the reaction force torque according to a difference in lateral acceleration for each vehicle speed, and determining the reaction force torque according to the lateral acceleration difference value and the vehicle speed using the reaction force torque map.