This paper focuses on the steering feel generation in SbW vehicles and is devoted to the related design of an intelligent mechatronic system, consisting of the hand wheel actuator as hardware unit and the computation of the desired steering torque as control algorithm. The paper finds another application field in driving Simulators (DSs), where the task of the steering feel generation also needs to be completed. The first part addresses the control of the hand wheel actuator in SbW vehicles. A model for the computation of the desired steering torque which the driver should feel is presented. The introduced steering torque computation does not only aim to generate a realistic steering feel. This means that the driver should not miss the basic steering functionality of modern conventional steering systems such as an electric power steering (EPS) or hydraulic power steering (HPS), and this in every driving situation. Moreover, the modular structure of the steering torque computation combined with suitably selected tuning parameters has the objective to offer a high degree of customisability of the steering feel and thus to provide to each driver with his preferred steering feel in a highly efficient manner. The modules of the steering torque computation are firstly described before its objective evaluation follows. The second part deals with the design of the hand wheel actuator as haptic device in SbW vehicles. The hand wheel actuator must be carefully designed to achieve an optimal realisation of the computed desired steering torque. This should be transmitted to the steering wheel ideally without phase and amplitude changes that can be perceived by the driver as disturbing. In this case, the hand wheel actuator thus leads to a considerable degradation of the computed steering feel. Requirements analyses must be performed by applying a systematic method in order to derive specifications for an optimal hand wheel actuator which aims to generate a target steering feel in combination with the steering torque computation as control algorithm. The present paper explains the adopted method using the example of a hand wheel actuator prototype, for which a set of specifications concerning friction, damping, inertia, time delay, motor current control, motor torque speed characteristics, cogging torque and resolution of the steering wheel angle's measurement is extracted.
Steering feel generation in steer-by-wire vehicles - modular steering torque computation and requirements for the hand wheel actuator
2014
58 Seiten, Bilder, Tabellen, 37 Quellen
Conference paper
English
Steering Wheel Torque Control of Steer-by-Wire System for Steering Feel
British Library Conference Proceedings | 2017
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