System Identification Method for Brake Particle Emission Measurements of Passenger Car Disc Brakes on a Dynamometer 2018-01-1884
System identification method for brake particle emission measurements of passenger car disc brakes on a dynamometer
Similar to particulate emissions from engine exhausts, which are already regulated by emission standards, passenger car disc brakes are a source of particulate matter. According to various estimations brake particle emissions contribute to all traffic related emissions with two-digit percentage share and reduction of brake dust emissions is subject of current research. For the purpose of reducing brake dust emissions by choosing low-emission operating points of the disc brake, the knowledge of the emission behavior depending on brake pressure, wheel speed, temperature and friction history is of interest. According to the current state of research, theoretical white box modeling of the emission behavior is complicated due to the complexity of tribological contact between pad and disc. Thus experimental black box modeling is supposed to describe emission behavior. In order to minimize the influence of disturbances and therefore to improve prediction accuracy of such empirical models, system identification methods based on periodical test signals, such as brake pressure sine, are used for this application. To adopt these test signals, which are established in transfer function measurements, to the application of brake particle measurements and to develop an experimental design, system theoretical quantities, such as cutoff frequency, signal to noise ratio and hysteresis, are determined in dynamometer tests. Therefor measurements of the system’s response to step and sine test signals are analyzed. System identification is executed and the applicability of periodical test signals to brake particle measurements is proved.
Hartmut Niemann, Hermann Winner, Christof Asbach, Heinz Kaminski, Marco Zessinger
Technische Universitat Darmstadt, IUTA Duisburg, Link Europe