# US 12,179,742 B2 · Method and apparatus for controlling vehicle stability > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,179,742 B2 - Document ID: US12179742B2 - Status: Granted - Kind: B2 - Application number: 17/964,159 - Filed: 2022-10-12 - Published: 2023-11-02 - Granted: 2024-12-31 - Earliest claimed: 2022-04-29 - Assignees: Hyundai Mobis Co., Ltd. - Applicants: Hyundai Mobis Co., Ltd. - Inventors: Flavio Montalbano; Lorenzo Pinto - Web page: https://patentgrep.com/patent/US12179742B2 ## CPC - B60W 30/02: Control of vehicle driving stability - B60W 30/045: Improving turning performance - B60W 10/04: including control of propulsion units - B60W 10/184: with wheel brakes - B60W 30/18172: {Preventing, or responsive to skidding of wheels} - B60W 40/068: Road friction coefficient - B60W 40/101: Side slip angle of tyre - B60W 40/103: Side slip angle of vehicle body - B60W 2510/20: Steering systems - B60W 2520/125: Lateral acceleration - B60W 2520/14: Yaw - B60W 2520/20: Sideslip angle - B60W 2520/28: Wheel speed - B60W 2540/18: Steering angle - 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 A vehicle stability control method includes collecting steering information from a sensor of a vehicle, calculating a saturation index of a front axle of the vehicle or a rear axle of the vehicle using the steering information, and controlling an application of the vehicle based on the saturation index. ## Claims ### Claim 1 A vehicle stability control method performed by a vehicle stability control apparatus, the method comprising: collecting steering information from a sensor of a vehicle; calculating a saturation index of a front axle of the vehicle or a rear axle of the vehicle using the steering information; and controlling an application of the vehicle based on the saturation index, wherein the calculating includes determining whether the front axle is saturated by using a slip angle and a slip angular velocity of a front wheel tire, and determining whether the rear axle is saturated by using a slip angle and a slip angular velocity of a rear wheel tire, and wherein the controlling includes controlling an Active Yaw Control (AYC) for adjustment between agility intervention and stabilizing intervention using the saturation index. ### Claim 2 (depends on 1) The vehicle stability control method of claim 1, wherein the steering information includes a yaw rate, a steering wheel angle, a wheel speed, and a lateral acceleration. ### Claim 3 (depends on 2) The vehicle stability control method of claim 2, further comprising: estimating a maximum road friction coefficient using the steering information; storing the maximum road friction coefficient; and updating the maximum road friction coefficient in response to a reset condition being satisfied. ### Claim 4 (depends on 1) The vehicle stability control method of claim 1, wherein the controlling includes activating agility intervention when the rear axle is within a stable region and the front axle is out of the stable region, and controlling the AYC to deactivate the agility intervention when the front axle enters the stable region. ### Claim 5 (depends on 4) The vehicle stability control method of claim 4, wherein the controlling includes controlling the AYC to reduce the agility intervention when the rear axle is out of the stable region. ### Claim 6 (depends on 4) The vehicle stability control method of claim 4, wherein the controlling includes controlling the AYC to expand the stabilization intervention when the rear axle is out of the stable region. ### Claim 7 A vehicle stability control apparatus comprising: a data collector configured to collect steering information from a sensor of a vehicle; a calculator configured to calculate a saturation index of a front axle of the vehicle or a rear axle of the vehicle using the steering information; and a controller configured to control an application of the vehicle based on the saturation index, wherein the calculator is configured to determine whether the front axle is saturated using a slip angle and a slip angular velocity of a front wheel tire and whether the rear axle is saturated using a slip angle and a slip angular velocity of a rear wheel tire, and wherein the controller is configured to control an Active Yaw Control (AYC) for adjustment between agility intervention and stabilization intervention using the saturation index. ### Claim 8 (depends on 7) The vehicle stability control apparatus of claim 7, wherein the controller is configured to control the AYC to activate agility intervention when the rear axle is within a stable region and the front axle is out of the stable region, and to deactivate the agility intervention when the front axle enters the stable region. ### Claim 9 (depends on 7) The vehicle stability control apparatus of claim 7, further comprising: an estimator configured to estimate a maximum road surface friction coefficient using the steering information; a storage configured to store the maximum road surface friction coefficient; and an update unit configured to update the maximum road surface friction coefficient in response to a reset condition being satisfied. ### Claim 10 A vehicle stability control method performed by a vehicle stability control apparatus, the method comprising: collecting steering information from a sensor of a vehicle; calculating a saturation index of a front axle of the vehicle or a rear axle of the vehicle using the steering information; and controlling an application of the vehicle based on the saturation index, wherein the calculating includes calculating the saturation index of the rear axle of the vehicle, and the controlling includes adjusting intervention of an Electronic Stability Control (ESC) or Rear Wheel Steering (RWS) based on the saturation index of the rear axle, and wherein the controlling includes controlling the RWS as a master actuator when the saturation index of the rear axle is lower than a reference index and controlling the ESC as the master actuator when the saturation index of the rear axle is higher than the reference index.