US 11,987,252 B2
Systems and methods for determining whether a vehicle is in an understeer or oversteer situation
Naser Mehrabi, Richmond Hill (CA); Saurabh Kapoor, Markham (CA); Seyedeh Asal Nahidi, North York (CA); SeyedAlireza Kasaiezadeh Mahabadi, Novi, MI (US); James H Holbrook, Fenton, MI (US); Hualin Tan, Novi, MI (US); and Bakhtiar B Litkouhi, Washington, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Sep. 8, 2021, as Appl. No. 17/447,192.
Prior Publication US 2023/0079933 A1, Mar. 16, 2023
Int. Cl. B62D 15/02 (2006.01); B60W 40/101 (2012.01)
CPC B60W 40/101 (2013.01) [B62D 15/021 (2013.01); B60W 2510/207 (2013.01); B60W 2520/263 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A processor-implemented method for determining whether a vehicle with a first axle and a second axle is in an understeer or oversteer situation, the method comprising:
receiving, from an inertial measurement unit (IMU), IMU measurements for the vehicle, the IMU measurements comprising a lateral acceleration and a yaw rate;
receiving a longitudinal speed;
receiving, from an electric power-steering system (EPS), EPS signals comprising a steering angle, steering angular velocity, and a torque measurement;
determining, by a processor, that the first axle is steered by the EPS, and the second axle is not steered by the EPS;
determining, by the processor, a saturation level of the first axle based on the IMU measurements and the EPS signals;
determining, by the processor, a saturation level of the second axle based on the steering angle, the longitudinal speed, and the yaw rate;
integrating the saturation level of the first axle and the saturation level of the second axle;
determining, by the processor, that the vehicle is in an understeer or oversteer situation as a function of the integrated saturation levels, and an understeering angle; and
in response to the determining that the vehicle is in an understeer or oversteer situation, generating, by the processor, control signals for actuators of a drive system to smooth a vehicle response.