Electro-pneumatic braking systems are described and an outline is given of recent developments, particularly a new prototype system designed by the German manufacturer Bosch. Operational fears are lessened by the preservation of the straight air system as a back-up. Electronics can continuously modify braking to give the optimum distribution of effort to individual wheels. Separate anti-skid control units are not needed and the dynamic sensing of load transfer is possible. Response and release times are almost halved, and it is considered possible that stopping distances could be ten per cent less. Examples are given of typical arrangements for a two-axle motive unit and a three-axle trailer. Fault identification is provided through three routes: instrument panel warning lights; a built-in analysis system; and a socket for a separate test unit. At present the cost is expected to be more than an existing air system, but as more functions are brought into the control unit the electronic system should beless costly and easier to maintain than conventional braking arrangements
Abstract