Since ZF-TRW first launched the Electric Parking Brake System (EPB) in 2001 the market demand for this technology was continuously growing. Meanwhile the EPB is available in all vehicle platforms and produced globally. The production of the 60 millionth EPB caliper in 2015 was a remarkable milestone.
Technically the EPB interacts with several other driver assistance systems and therefore is not only required as a conventional park brake but more and more to further improve the overall safety, performance and comfort of passenger cars on the path to autonomous driving. In recent years new EPB suppliers entered the globally growing market and OEMs started to individually develop specifications for EPB systems. So there is a growing need to establish globally harmonized standards to efficiently release a safe EPB system on both, OEM and OES side to avoid distortion of competition.
Within the VDA, working groups were formed who deal with system development, fatigue and durability testing. This paper gives an overview of the status and results achieved so far. It has been agreed on mechatronic system endurance tests with actuator, calliper, ECU and Software. Load collectives, temperature- and pressure profiles have been aligned. Experience in actual projects shows that so far achievements of the working groups are very much appreciated by the global braking industry. Environmental component tests should be aligned in a similar way. Standards from ISO16750 could be tailored to the EPB needs. Another fundamental area is the alignment of core tests and regression test strategies.
Dr. Reitz, Andreas*, Loehr, Bert, Kohrt, Jens-Peter, ZF-TRW Active & Passive Safety Technology, Germany