Evasive steering assist modification based on manual steering inputs
The techniques and systems herein enable ESA modification based on manual steering inputs. Specifically, a score is determined for a manual steering input to a host vehicle while an ESA is actively applying an ESA steering input to the host vehicle. The score quantifies an amount of additional steering input relative to the ESA steering input (e.g. additional steering angle, steering wheel torque). The ESA steering input is maintained, modified, or canceled based on the score. By doing so, the system is able to effectively adapt the ESA to the manual steering inputs thereby allowing for effective collision mitigation while ensuring that the vehicles operate as intended by the drivers.
1. A method comprising:
determining that an evasive steering assist (ESA) of a host vehicle is providing an ESA steering input to the host vehicle to avoid a collision with a target;
determining a manual steering input to the host vehicle provided by a driver of the host vehicle;
determining an expected steering angle provided by the ESA steering input to the host vehicle;
determining a manual steering torque applied by the driver to a steering column of the host vehicle;
determining an additional steering angle provided by the driver relative to the ESA steering input based on a difference between the manual steering input and the expected steering angle;
calculating a score using a Sigmoid function based on the additional steering angle and the manual steering torque, the score quantifying an amount of additional steering input provided by the manual steering input relative to the ESA steering input and being calculated based on a sum of (i) a product of a weighting constant and the Sigmoid function of the additional steering angle, and (ii) a product of one minus the weighting constant and the Sigmoid function of the manual steering torque;
determining whether the score meets a first threshold for modifying the ESA steering input;
determining whether the score meets a second threshold that is higher than the first threshold for canceling the ESA steering input;
responsive to the score not meeting the first threshold, maintaining the ESA steering input;
responsive to the score meeting the first threshold but not meeting the second threshold, adjusting, based on the additional steering angle, the ESA steering input to provide a different ESA steering input than the ESA steering input prior to adjustment; and
responsive to the score meeting the second threshold, canceling the ESA steering input and allowing the driver to manually steer the host vehicle.
2. The method of claim 1 , wherein the manual steering torque is calculated as a moving average of torques applied by the driver to the steering column of the host vehicle.
3. The method of claim 1 , further comprising:
determining a path corresponding to the ESA steering input, wherein the adjusting the ESA steering input comprises modifying the path.
4. The method of claim 3 , wherein the modifying the path is based on the difference between the manual steering input and the expected steering angle.
5. The method of claim 4 , wherein the modifying the path comprises:
determining a destination point of the path;
generating a modified destination point based on the difference between the manual steering input and the expected steering angle;
generating a polynomial representing a modified path from a current location of the host vehicle to the modified destination point; and
adapting the path to the polynomial.
6. A system comprising at least one processor configured to:
determine that an evasive steering assist (ESA) of a host vehicle is providing an ESA steering input to the host vehicle to avoid a collision with a target;
determine a manual steering input to the host vehicle provided by a driver of the host vehicle;
determine an expected steering angle provided by the ESA steering input to the host vehicle;
determine a manual steering torque applied by the driver to a steering column of the host vehicle;
determine an additional steering angle provided by the driver relative to the ESA steering input based on a difference between the manual steering input and the expected steering angle;
calculate a score using a Sigmoid function based on the additional steering angle and the manual steering torque, the score quantifying an amount of additional steering input provided by the manual steering input relative to the ESA steering input and being calculated based on a sum of (i) a product of a weighting constant and the Sigmoid function of the additional steering angle, and (ii) a product of one minus the weighting constant and the Sigmoid function of the manual steering torque;
determine whether the score meets a first threshold for adjusting the ESA steering input;
determine whether the score meets a second threshold that is higher than the first threshold for canceling the ESA steering input;
responsive to the score not meeting the first threshold, maintain the ESA steering input;
responsive to the score meeting the first threshold but not meeting the second threshold, adjust, based on the additional steering angle, the ESA steering input to provide a different ESA steering input than the ESA steering input prior to adjustment; and
responsive to the score meeting the second threshold, canceling the ESA steering input and allowing the driver to manually steer the host vehicle.
7. The system of claim 6 , wherein the manual steering torque is calculated as a moving average of torques applied by the driver to the steering column of the host vehicle.
8. The system of claim 6 , wherein the at least one processor is further configured to, determine a path corresponding to the ESA steering input, wherein adjusting the ESA steering input comprises modifying the path.
9. The system of claim 8 , wherein the at least one processor is further configured to modify the path based on the difference between the manual steering input and the expected steering angle.
10. The system of claim 9 , wherein the at least one processor is further configured to modify the path by:
determining a destination point of the path; and
generating a modified destination point based on the difference between the manual steering input and the expected steering angle.
11. The system of claim 10 , wherein the at least one processor is further configured to modify the path by:
generating a polynomial representing a modified path from a current location of the host vehicle to the modified destination point; and
adapting the path to the polynomial.
12. A non-transitory computer-readable storage media comprising instructions that, when executed by at least one processor, cause the processor to:
determine that an evasive steering assist (ESA) of a host vehicle is providing an ESA steering input to the host vehicle to avoid a collision with a target;
determine a manual steering input to the host vehicle provided by a driver of the host vehicle;
determine an expected steering angle provided by the ESA steering input to the host vehicle;
determine a manual steering torque applied by the driver to a steering column of the host vehicle;
determine an additional steering angle provided by the driver relative to the ESA steering input based on a difference between the manual steering input and the expected steering angle;
calculate a score using a Sigmoid function based on the additional steering angle and the manual steering torque, the score quantifying an amount of additional steering input provided by the manual steering input relative to the ESA steering input and being calculated based on a sum of (i) a product of a weighting constant and the Sigmoid function of the additional steering angle, and (ii) a product of one minus the weighting constant and the Sigmoid function of the manual steering torque;
determine whether the score meets a first threshold for adjusting the ESA steering input;
determine whether the score meets a second threshold that is higher than the first threshold for canceling the ESA steering input;
responsive to the score not meeting the first threshold, maintain the ESA steering input;
responsive to the score meeting the first threshold but not meeting the second threshold, adjust, based on the additional steering angle, the ESA steering input to provide a different ESA steering input than the ESA steering input prior to adjustment; and
responsive to the score meeting the second threshold, canceling the ESA steering input and allowing the driver to manually steer the host vehicle.