Multi-source error analysis for loading disk of suspension kinematics & compliance test bench

The suspension Kinematics & compliance (K&C) characteristics test bench can simulate the excitation of the road to the wheels under various typical working conditions in a quasi-static manner on the bench, enabling the measurement of the K&C characteristics of the suspension system without knowing the specific suspension structure form, parameters, etc., assisting in the entire design process of the vehicle. In this paper, aiming at various geometric source errors existing in the processing and assembly process of the K&C characteristic test bench, an evaluation method based on the homogeneous transformation matrix is proposed to establish the position error of the center of the end loading disk in the series motion chain. Firstly, the mapping relationship between the position error of the end loading disk in the series mechanism kinematic chain and the assembly error is established by using the homogeneous transformation matrix. Then, the change matrix of the coordinate system from the i-th to the (i-1)-th when deformed under load is calculated through the finite element analysis results. Finally, the theoretical error range of the contact point between the loading bench and the tire is obtained by combining the assembly error and the error caused by deformation.