Multi-Objective Control of Dynamic Chassis Considering Road Roughness Class Recognition 2021-01-0322

For the DCC (Dynamic Chassis Control) system, in addition to the requirement of ride and comfort, it is also necessary to consider the requirement of handling and stability, and these two requirements are often not met at the same time. This poses a great challenge to the design of the controller, especially in the face of complex working conditions. In order to solve this problem, this paper proposes a comprehensive DCC controller that considers road roughness class recognition. Firstly, a quarter vehicle model is established, the road surface roughness is calculated from the vertical acceleration of the wheels measured by the sensors. Then we calculate the autocorrelation function and the Fourier transform to estimate the PSD (Power Spectral Density) to get the road roughness class. Then control algorithms are designed for the vertical motion control, roll control and pitch control. The vertical motion control is based on the improved skyhook control considering the class of road roughness to achieve a better control effect, and the roll and pitch movements are controlled by the sliding mode variable structure control and state feedback control. Finally, the fuzzy logic control based on designed membership functions and fuzzy rules is used to couple the forces calculated from these three targets and calculate the actual control force of each shock absorber. In order to verify the control algorithm, this paper builds virtual scenes including double-line-change test roads and long straight roads with different road roughness classes based on the Unity 3D engine, and uses a six-degree-of-freedom driving simulator to conduct simulation experiments. Compared with the method of skyhook control, the comprehensive control algorithm designed in this paper can achieve better results in terms of ride and comfort, handling and stability requirements.