Electric brake position and force sensing and control

• US 20050269872A1
• Filed: 06/03/2005
• Published: 12/08/2005
• Est. Priority Date: 06/04/2004
• Status: Abandoned Application

• Current Assignee: Goodrich Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Goodrich Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Ralea, Mihai
• Application Number:
  US11/145,138
• Publication Number:
  US 20050269872A1
• Time in Patent Office: Days
• US Class Current: 303/20
• CPC Class Codes: B60T 13/741 acting on an ultimate actuator
• CPC Class Codes: B60T 8/00 Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force by changing number of effective brake cylinders in power brake systems B60T17/10
• CPC Class Codes: B60T 8/1703 for aircrafts
• CPC Class Codes: F16D 2066/003 Position, angle or speed
• CPC Class Codes: F16D 2066/005 Force, torque, stress or strain
• CPC Class Codes: F16D 2121/24 using motors
• CPC Class Codes: F16D 2125/40 Screw-and-nut
• CPC Class Codes: F16D 2125/48 with parallel stationary axes, e.g. spur gears
• CPC Class Codes: F16D 2125/50 with parallel non-stationary axes, e.g. planetary gearing
• CPC Class Codes: F16D 2125/52 with non-parallel stationary axes, e.g. worm or bevel gears
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes

Abstract

A brake system including an electromechanical brake actuator having an actuator ram for exerting a brake force on a brake stack of a wheel to be braked in response to a control signal. In addition, the brake system includes a force sensor for sensing the brake force exerted on the brake stack by the actuator ram and outputting a force feedback signal based thereon; and a position sensor for sensing a position of the actuator ram and outputting a position feedback signal based thereon. Moreover, the brake system includes a controller for providing the control signal to the electromechanical brake actuator based on the force feedback signal and the position feedback signal.

Claims

1. An electromechanical brake system, comprising:

an electromechanical brake actuator including an actuator ram for exerting a brake force on a brake stack of a wheel to be braked in response to a control signal;

a force sensor for sensing the brake force exerted on the brake stack by the actuator ram and outputting a force feedback signal based thereon;

a position sensor for sensing a position of the actuator ram and outputting a position feedback signal based thereon; and

a controller for providing the control signal to the electromechanical brake actuator based on the force feedback signal and the position feedback signal.

2. The electromechanical brake system of claim 1, wherein the controller provides closed loop force control during a braking event and closed loop position control to provide a desired running clearance during a non-braking event.

3. The electromechanical brake system of claim 1, wherein the controller receives as an input a force command signal representative of an operator requested braking event.

4. The electromechanical brake system of claim 1, wherein the controller receives as an input a force command signal representative of an anti-skid control based braking event.

5. The electromechanical brake system of claim 1, wherein the position sensor comprises a resolver.

6. The electromechanical brake system of claim 5, wherein the electromechanical brake actuator comprises a motor for driving the actuator ram, and the controller also uses an output of the resolver to determine appropriate phasing of power signals provided to the motor for commutation.

7. The electromechanical brake system of claim 1, wherein the position sensor comprises an LVDT sensor.

8. The electromechanical brake system of claim 1, wherein the position sensor provides relative positioning.

9. The electromechanical brake system of claim 1, wherein the position sensor provides absolute positioning.

10. The electromechanical brake system of claim 1, wherein the force sensor comprises a force load cell.

11. The electromechanical brake system of claim 1, further comprising at least one additional electromechanical brake actuator and actuator ram for exerting a brake force on the brake stack of the wheel to be braked in response to a control signal, and a corresponding at least one additional force sensor and position sensor for outputting a force feedback signal and position feedback signal, respectively.

12. The electromechanical brake system of claim 1, wherein the controller includes a switch whereby the controller switches between closed loop force control and closed loop position control.

13. The electromechanical brake system of claim 12, wherein the controller includes a mode detector for detecting a braking event versus a non-braking event, and the mode detector controls the switch based thereon.

14. The electromechanical brake system of claim 13, wherein the mode detector detects a braking event versus a non-braking event based on an output of the force sensor.

15. The electromechanical brake system of claim 14, wherein te mode detector detects a braking event based on detecting the output of the force sensor representing at least a predetermined amount of brake force.

16. The electromechanical brake system of claim 1, wherein the controller provides closed loop position servo control to control brake force application in response to an external command during a braking event.

17. The electromechanical brake system of claim 16, wherein during the braking event the controller adjusts for brake fade based on the force feedback signal.

18. The electromechanical brake system of claim 1, wherein the controller provides closed loop force servo control to control brake force application in response to an external command during a braking event.

19. The electromechanical brake system of claim 18, wherein the controller provides a desired running clearance based on the position feedback signal.

20. The electromechanical brake system of claim 19, wherein the position feedback signal is compared to a position command signal derived from the external command.

21. The electromechanical brake system of claim 1, wherein the wheel is the wheel of an aircraft.

22. An electromechanical brake actuator, comprising:

an actuator ram for exerting a brake force on a brake stack of a wheel to be braked in response to a control signal;

a force sensor for sensing the brake force exerted on the brake stack by the actuator ram and outputting a force feedback signal based thereon; and

a position sensor for sensing a position of the actuator ram and outputting a position feedback signal based thereon.