A growing interest in x-by-wire systems is discernible in the automotive industry. In 2022, a first manufacturer announced to launch the production of a brake-by-wire pedal in 2025. By-wire pedals remove the mechanical backup as it is in place in current systems as Bosch’s iBooster. The removal of the mechanical backup raises significant safety challenges. This topic is addressed by many publications in the preceding years concluding that an at least triplex redundancy is necessary to guarantee safety. This contribution identifies the failure rates of the components that a future brake-by-wire pedal will be built of. Furthermore, the safety of duplex, triplex and quadruplex pedal boxes is discussed for a two-brake-circuit design. Additionally, external sensor data that might be available within an automobile is considered, as well. Therefore, it is assessed what consequences for safety could evolve, if brake ECUs (electronic control units) had access to accelerator pedal sensor data or environmental data (LiDAR etc.), called virtual sensor to diagnose sensor faults. It is found that already duplex sensor systems, if virtual sensors are attached, could satisfy required safety.
Safety Concepts for Brake-by-Wire Pedal Boxes
19.07.2023
1562539 byte
Aufsatz (Konferenz)
Elektronische Ressource
Englisch