Fast Modelling and Identification of Hydraulic Brake Plants for Automotive Applications

Abstract

Diffusion of electric and hybrid vehicles is accelerating the development of innovative braking technologies. Calibration of accurate models of a hydraulic brake plant involves availability of large amount of data whose acquisition is expensive and time consuming. Also, for some applications, such as vehicle simulators and hardware in the loop test rig, a real-time implementation is required. To avoid excessive computational loads, usage of simplified parametric models is almost mandatory. In this work, authors propose a simplified functional approach to identify and simulate the response of a generic hydraulic plant with a limited number of experimental tests. To reproduce complex nonlinear behaviours that are difficult to be reproduced with simplified models, piecewise transfer functions with scheduled poles are proposed. This innovative solution has been successfully applied for the identification of the brake plant of an existing vehicle, a Siemens prototype of instrumented vehicle called SimRod, demonstrating the feasibility of proposed method.

Stability characteristics and experiment of hydraulic drive four-wheel chassis

“…The test conditions are set as follows: a throttle control device is installed on the chassis to keep the engine running at a constant output speed so as to maintain the chassis speed at the same level while driving in a straight line (Ghodki et al , 2020; Pugi et al , 2020). A speed tester is installed on each side of the four chassis driving wheels to check whether the chassis is running at the same speed.…”

HIL testing of wheel slide protection systems: criteria for continuous updating and validation

“…Reference pilot pressure for pneumatic amplifiers is provided by a model of the brake distributor. Distributor is simulated with a piecewise linearized model, an approach that is often adopted for real-time applications [26]. There is no need to simulate brake pipe dynamics since WSP tests are performed on single coaches, so delays associated with propagation along the pipe are almost negligible.…”

Regenerative braking torque compensation control based on improved ADRC

“…Friction makes the system produce crawling phenomenon and dead zone, which seriously affect the response speed and hydraulic control. 19 In order to realize the accurate hydraulic control of EHB system, it is necessary to accurately estimate the equivalent friction F hf of the whole hydraulic system. 20 LuGre friction model is introduced here to estimate it.…”