Methods and systems for automated control of vehicle braking

• US 20090043470A1
• Filed: 08/10/2007
• Published: 02/12/2009
• Est. Priority Date: 08/10/2007
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation
• Original Assignee: Toyota Motor Corporation
• Inventors: Ahn, Samuel S.
• Granted Patent: US 8,027,773 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 40/09 Driving style or behaviour

Abstract

Method and systems for automated anticipatory braking of a vehicle are provided. In one embodiment, the system comprises a vehicle accelerator movable between a maximum speed position and a minimum speed position, and a sensor configured to determine the rate of travel of the accelerator toward the minimum speed position. The system further comprises a controller configured to utilize the rate of travel of the accelerator to determine if a rapid braking condition is desired, and to provide a control signal to apply increased negative torque to the drive wheels of the vehicle prior to the user applying the vehicle brake. In some embodiments, driver history and/or other vehicle conditions are taken into account. In some embodiments, negative torque is applied via varying of valve timing, control of combustion chamber intake, control of exhaust backpressure, control of motor energy, and/or shifting of a transmission to a numerically higher speed ratio.

Claims

1. A system for automated braking of a vehicle, comprising:

a vehicle accelerator movable between a maximum speed position and a minimum speed position;

a vehicle brake;

a sensor configured to determine the rate of travel of the accelerator toward the minimum speed position;

a controller configured to utilize the rate of travel to determine if a rapid braking condition is desired, and to provide a control signal to apply increased negative torque to the drive wheels of the vehicle prior to the user applying the vehicle brake; and

a vehicle component configured to affect the torque on the drive wheels and to apply negative torque to the drive wheels in response to the signal.

2. The system as recited in claim 1, further comprising:

a vehicle condition detector configured to detect a vehicle condition and to communicate with the controller, wherein the controller is configured to provide the signal only if the vehicle condition is present.

3. The system as recited in claim 2, wherein the detector comprises at least one of a vehicle steering detector, a vehicle speed detector, an engine speed detector, a transmission detector, and a motor torque detector.

4. The system as recited in claim 1, wherein the sensor comprises at least one of an accelerator pedal sensor, a throttle sensor, and a processor configured to calculate accelerator travel rate.

5. The system as recited in claim 1, wherein the vehicle component comprises an internal combustion engine, and wherein controller and the control signal are configured to control the timing of intake and exhaust valves of the internal combustion engine.

6. The system as recited in claim 1, wherein the vehicle component comprises an internal combustion engine, and wherein the controller and control signal are configured to control the opening amount of a limiting device placed before the combustion chamber of the engine.

7. The system as recited in claim 1, wherein the vehicle component comprises a valve in an exhaust path of the vehicle, wherein the valve is configured to control exhaust backpressure in the exhaust path, and wherein the controller and control signal are configured to control the valve.

8. The system as recited in claim 1, wherein the vehicle component comprises a transmission and wherein the controller and control signal are configured to shift the transmission to a numerically higher speed ratio.

9. The system as recited in claim 1, wherein the vehicle component comprises a motor/generator coupled to a drive shaft and wherein the controller and control signal are configured to control the amount of energy generated per revolution of the drive shaft.

10. A method for automated braking of a vehicle, comprising:

monitoring the rate of travel of an accelerator pedal in a deceleration direction;

determining if the rate of travel surpasses a threshold level; and

if the threshold level is surpassed, braking the motor vehicle by controlling the negative torque on the drive wheels of the vehicle.

11. The method as recited in claim 10, further comprising determining if certain vehicle conditions exist;

and

allowing the braking to occur only if the vehicle conditions are present.

12. The method as recited in claim 11, wherein the vehicle conditions comprises at least one of road grade conditions, steering conditions, wheel conditions, engine conditions, motor conditions, and transmission conditions.

13. The method as recited in claim 10, wherein the negative torque on the drive wheels is controlled by varying the timing of intake and exhaust valves in an internal combustion engine.

14. The method as recited in claim 10, wherein the negative torque on the drive wheels is controlled by varying the amount of energy generated per revolution of an electric motor/generator.

15. The method as recited in claim 10, wherein the negative torque on the drive wheels is controlled by moving a transmission to a numerically higher speed ratio.

16. The method as recited in claim 10, wherein the rate of travel is monitored by sensing the positions of an accelerator pedal between points in time and calculating the rate based upon the positions.

17. The method as recited in claim 10, wherein an electronic controller carries out the determining and braking operations.

18. A system for automated braking of a vehicle, comprising:

a sensor configured to determine at least one of position and rate of movement of a driver accelerator; and

a controller in communication with the sensor and configured to generate a control signal configured to apply negative torque to the drive wheels of a vehicle in response to a predetermined high rate of movement of a driver accelerator control in a decreased speed direction of the driver accelerator.

19. The system as recited in claim 18, wherein the controller and sensor are integral.

20. The system as recited in claim 18, wherein the control signal comprises at least one of an intake valve control signal, an exhaust valve control signal, a motor control signal, and a transmission control signal.