Method and system for controlling an engine and transmission using a dual request closed loop request
View Patent ↗A method and control module for operating a vehicle powertrain in response to a cruise control includes a primary closed loop control module generating a primary closed loop control signal and a primary torque request signal based on the primary closed loop control signal. The control module also includes a secondary closed loop control module generating a secondary closed loop control signal and a secondary torque request signal based on the secondary closed loop control signal. A transmission control module controls a transmission based on the primary torque request control signal and the secondary torque request signal.
1. A method comprising:
activating a cruise control system;
generating a primary closed loop control signal;
generating a primary torque request signal based on the primary closed loop control signal;
generating a secondary closed loop control signal;
generating a secondary torque request signal based on the secondary closed loop control signal; and
controlling a transmission based on the primary torque request signal and the secondary torque request signal.
2. A method as recited in claim 1 wherein generating the primary closed loop control signal comprises generating the primary closed loop control signal in response to a primary acceleration error signal.
3. A method as recited in claim 2 further comprising generating the primary acceleration error signal in response to a measured acceleration signal and a predicted acceleration signal.
4. A method as recited in claim 3 further comprising generating the predicted acceleration signal based on a vehicle model and a limited cruise torque request.
5. A method as recited in claim 1 wherein generating the primary torque request signal comprises generating the primary torque request signal based on a desired vehicle acceleration and a vehicle model.
6. A method as recited in claim 1 wherein generating the secondary closed loop control signal comprises generating the secondary closed loop control signal based on a secondary acceleration error.
7. A method as recited in claim 1 further comprising generating a secondary acceleration error signal based on a desired acceleration signal and a predicted acceleration signal.
8. A method as recited in claim 7 further comprising generating the predicted acceleration signal based on a vehicle model and a limited cruise torque request.
9. A method as recited in claim 1 wherein generating the secondary torque request signal comprises generating the secondary torque request signal based on a torque ratio signal.
10. A method as recited in claim 9 further comprising generating the torque ratio signal based on a cruise torque request and a maximum axle torque ratio.
11. A method as recited in claim 10 wherein generating the secondary closed loop control signal comprises generating the secondary closed loop control signal based on the torque ratio signal.
12. A method as recited in claim 11 wherein generating the secondary closed loop control signal comprises generating the secondary closed loop control signal based on the torque ratio signal and a vehicle speed signal.
13. A method as recited in claim 1 further comprising determining an accelerator effective pedal position based on the primary torque request signal and the secondary torque request signal.
14. A control module for operating a vehicle powertrain in response to a cruise control comprising:
a primary closed loop control module generating a primary closed loop control signal and a primary torque request signal based on the primary closed loop control signal;
a secondary closed loop control module generating a secondary closed loop control signal and a secondary torque request signal based on the secondary closed loop control signal; and
a transmission control module controlling a transmission based on the primary torque request signal and the secondary torque request signal.
15. A control module as recited in claim 14 further comprising a primary acceleration error module generating a primary acceleration error signal and wherein the primary closed loop control module generates the primary closed loop control signal in response to the primary acceleration error signal.
16. A control module as recited in claim 15 wherein the primary acceleration error signal is based on a measured acceleration signal and a predicted acceleration signal.
17. A control module as recited in claim 15 wherein the primary torque request signal is based on a desired vehicle acceleration and a vehicle model.
18. A control module as recited in claim 15 wherein generating the secondary closed loop control signal comprises generating the secondary closed loop control signal based on a secondary acceleration error signal.
19. A control module as recited in claim 18 wherein the secondary acceleration error signal is based on a desired acceleration signal and a predicted acceleration signal.
20. A control module as recited in claim 14 wherein the secondary torque request signal is based on a torque ratio signal.