HBS Communications and Control
Understanding the communication and control architectures is crucial to be able to acknowledge the HBS failure behaviour. The first thing to note is that communications are mounted on top of the Time-Triggered Protocol for safety-critical distributed real-time control systems (TTP/C). In TTP/C every element that uses the communication system is allocated with a pre-defined slot of time to transmit.
The HBS includes a central control unit and four wheel processing nodes. In the central control unit, it is calculated the amount of braking force to be applied to each of the vehicle's wheels. This information is used to compute the braking torque to be developed by each of the actuators in the local Hybrid ABS CPUs.