Driver notification using handwheel actuators in steer-by-wire systems
According to one or more embodiments of the present invention a steer by wire steering system includes a deviation detection unit configured to determine a deviation signal that is indicative of a disturbance in one or more components coupled to a rack. The steer by wire steering system further includes a handwheel notification module configured to generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration. The steer by wire steering system further includes a handwheel control module that generates an input command corresponding to a reference torque generated by a road wheel actuator, a feedback torque for a driver is generated based on the input command. The handwheel control module further modifies the input command using the modification signal, the modification providing a notification corresponding to the disturbance to the driver.
1. A steer by wire steering system comprising:
a processor; and
a memory including instructions that, when executed by the processor, cause the processor to:
receive a deviation signal that is indicative of a disturbance experienced by one or more components coupled to a rack;
generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration;
generate an input command corresponding to a reference torque generated by a road wheel actuator;
generate a feedback torque for a driver based on the input command;
generate a modified input command using the input command and the modification signal; and
provide the modified input command to the driver, the modified input command providing a notification corresponding to the disturbance to the driver.
2. The steer by wire steering system of claim 1 , wherein the deviation signal is a plurality of deviation signals.
3. The steer by wire steering system of claim 2 , wherein the plurality of deviation signals is received from a plurality of deviation detection units.
4. The steer by wire steering system of claim 1 , wherein the modification signal is an input torque modification signal and the modified input command is a handwheel torque command corresponding to the reference torque.
5. The steer by wire steering system of claim 1 , wherein the modification signal is an output torque modification signal, and the modified input command is a motor torque command that is generated using a handwheel torque command and a measured handwheel torque.
6. The steer by wire steering system of claim 1 , wherein the modification signal is a voltage modification signal and generating the modified input command comprises:
generating a voltage command corresponding to the input command; and
modifying the voltage command using the voltage modification signal.
7. The steer by wire steering system of claim 6 , wherein the modification voltage command generates an audible notification for the driver.
8. The steer by wire steering system of claim 7 , wherein the modified voltage command is applied to a motor of a handwheel actuator to generate the feedback torque and the audible notification.
9. The steer by wire steering system of claim 1 , wherein generating the modification signal comprises at least one of:
frequency shifting the deviation signal;
amplitude scaling the deviation signal; and
applying a transfer function to the deviation signal.
10. A method for generating a driver notification in a steer by wire steering system, the method comprising:
determining, by a processor, a deviation signal that is indicative of a disturbance in one or more components coupled to a rack;
generating, by the processor, a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration;
generating, by the processor, a input command corresponding to a reference torque generated by a road wheel actuator;
generating, by the processor, a feedback torque for a driver based on the input command;
generating, by the processor, a modified input command using the input command and the modification signal; and
providing the modified input command to the driver, the modified input command providing a notification corresponding to the disturbance to the driver.
11. The method of claim 10 , wherein the deviation signal is a plurality of deviation signals.
12. The method of claim 10 , wherein the modification signal is an input torque modification signal and the modified input command is a handwheel torque command corresponding to the reference torque.
13. The method of claim 10 , wherein the modification signal is an output torque modification signal, and the modified input command is a motor torque command that is generated using a handwheel torque command and a measured handwheel torque.
14. The method of claim 10 , wherein the modification signal is a voltage modification signal and generating the modified input command comprises:
generating a voltage command corresponding to the input command; and
modifying the voltage command using the voltage modification signal.
15. The method of claim 14 , wherein the modification voltage command generates an audible notification for the driver.
16. A driver notification system comprising:
a processor; and
a memory including instructions that, when executed by the processor, cause the processor to:
receive a deviation signal in a rack force generated by a road wheel actuator;
generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration;
generate an input command corresponding to the rack force generated by the road wheel actuator;
generate a feedback torque for a driver based on the input command, the feedback torque providing one of a tactile feedback and an audible feedback via a steering handwheel component to the driver;
generate a modified input command using the input command and the modification signal; and
provide the modified input command to the driver, the modified input command providing a notification corresponding to the deviation to the driver.
17. The driver notification system of claim 16 , wherein the deviation signal is a plurality of deviation signals.
18. The driver notification system of claim 16 , wherein the modification signal is an input torque modification signal and the modified input command is a handwheel torque command corresponding to the rack force.
19. The driver notification system of claim 16 , wherein the modification signal is an output torque modification signal, and the modified input command is a motor torque command that is generated using a handwheel torque command and a measured handwheel torque.
20. The driver notification system of claim 16 , wherein the modification signal is a voltage modification signal and generating the modified input command comprises:
generating a voltage command corresponding to the input command; and
modifying the voltage command using the voltage modification signal.