Central Platform ECU for Advanced Driver Assistance
The brake-by-wire concept is the output of a joint project between Delphi and TTTech. Their goal was to develop a new electro-mechanical braking (EMB) system without any hydraulic brake components. It was to have a faster brake responding behavior, resulting in shorter braking distances and fulfilling higher safety requirements. The project focused on the design, evaluation, implementation and testing of a cross-company brake-by-wire application in a prototype based on a current series car model.
The design of an applicable E/E architecture for the by-wire application was started after the decision to use time-triggered communication as backbone for the brake-by-wire application was taken. Based on an active star coupler, the four electronic actuators with integrated ECUs were connected with the brake pedals. As system safety was one of the key requirements, a number of application fault models were assumed: data processing faults, data storage faults, data flow faults, control flow faults and control timing faults.
TTTech supplied the software components for the whole system. The wide range of its products covered automatic scheduling tools, node design tools, embedded software and tools for integration, manipulation and validation. With the design of the electro-mechanical braking system Delphi and TTTech demonstrated that economical and technical advantages could be achieved by replacing conventional hydraulic braking system with electrically driven actuators. The brake-by-wire system supported the integration of conventional electronics and additional by-wire functions.