Hydrostatic braking revisited

You are here: Homepage > Search

Hydrostatic braking revisited

Bonanno, Antonio / Zarotti, Luca G.

The paper addresses the problem of the 'hydrostatic braking' of a mobile machine driven by a hydrostatic transmission (a topic which lacks the attention of the scholars, though it involves the machine safety) by defining two different fields of investigation: the SAB (Short Arrest Braking) and the LOB (Long Overrun Braking). Within a virtual simulation environment, the effects of some modified displacement control laws - of pump and motor - and hardware changes on the overspeed of the diesel engine are tested and compared. The SAB braking has been analyzed in some detail by addressing the problem of the engine overspeed. Three possible solutions have been simulated and the relevant results compared; of major interest is the conclusion that significant benefits are possible if the standard assumption of a bidirectional control law of the displacement settings of the main transmission units (pump and motor) is abandoned and replaced by asymmetrical alternatives. The LOB braking has been analyzed in more general terms and its specific problems have been exemplified by means of a single case study. Of major interest here is the remark that the machine locomotion and the transmission control interact much more than in SAB braking and additional investigation are in progress to develop the relevant knowledge base.