System and method for controlling a vehicle brake to prevent vehicle roll away

An article of manufacture, comprising:

• a non-transitory computer storage medium having a computer program encoded thereon that, when executed by a parking brake controller of a brake control system for a vehicle, controls application of a parking brake, the brake control system including a fluid circuit including a first electropneumatic module configured to control fluid pressure in a brake actuator for a first wheel brake to apply and release a service brake and a second electropneumatic module configured to control fluid pressure in a brake actuator for one of the first wheel brake and a second wheel brake to apply and release the parking brake, the computer program include code for:
• determining whether the parking brake is in an applied state or a released state;
• determining whether a speed of the vehicle meets a predetermined condition relative to a predetermined speed;
• determining whether a command to move the service brake to an applied state has been issued by a service brake controller;
• identifying, when (i) the parking brake is in the released state, (ii) the speed of the vehicle meets the predetermined condition relative to the predetermined speed, and (iii) the command to move the service brake to the applied state has been issued by the service brake controller, an absence of communication on a communications bus;
• and,
• generating, after identifying the absence of communication on the communications bus, a parking brake control signal configured to cause the second electropneumatic module to exhaust fluid pressure from the brake actuator for the one of the first wheel brake and the second wheel brake to move the parking brake from the released state to an applied state.

A method for controlling application of a parking brake of a brake control system for a vehicle, the brake control system including a fluid circuit including a first electropneumatic module configured to control fluid pressure in a brake actuator for a first wheel brake to apply and release a service brake and a second electropneumatic module configured to control fluid pressure in a brake actuator for one of the first wheel brake and a second wheel brake to apply and release the parking brake, the method comprising:

• determining whether the parking brake is in an applied state or a released state;
• determining whether a speed of the vehicle meets a predetermined condition relative to a predetermined speed;
• determining whether a command to move the service brake to an applied state has been issued by a service brake controller;
• identifying, when (i) the parking brake is in the released state, (ii) the speed of the vehicle meets the predetermined condition relative to the predetermined speed, and (iii) the command to move the service brake to the applied state has been issued by the service brake controller, an absence of communication on a communications bus;
• and,
• generating, after identifying the absence of communication on the communications bus, a parking brake control signal configured to cause the second electropneumatic module to exhaust fluid pressure from the brake actuator for the one of the first wheel brake and the second wheel brake to move the parking brake from the released state to an applied state.