Damping adjustable semi-active suspension hybrid model predictive control method based on damping force constraints

Abstract

The invention discloses a damping adjustable semi-active suspension hybrid model predictive control method based on damping force constraints. The method comprises steps of establishing a semi-active suspension hybrid system model; based on the model predictive control theory, performing the finite time domain optimal control of the semi-active suspension hybrid system; and transforming it into a mixed integer quadratic programming problem with real and binary variables, to achieve the hybrid model predictive control of the damping adjustable semi-active suspension. The method has the advantages of solving the contradiction between comfort and handling stability; avoiding the nonlinear constraint condition in the semi-active suspension optimization method; converting the semi-active suspension control problem into the finite time domain constrained optimal control problem; and effectively solving the rolling time domain optimization problem with nonlinear constraints.

Description

Hybrid Model Predictive Control Method for Damping Adjustable Semi-Active Suspension Based on Damping Force Constraint technical field The invention relates to the technical field of automobile suspension control, in particular to a hybrid model predictive control method for adjustable damping semi-active suspension based on damping force constraints. Background technique Suspension systems are critical to improving the ride and handling of a car. The semi-active suspension system overcomes the technical defect that the stiffness and damping of the passive suspension cannot be adjusted, and its cost is much lower than that of the active suspension, which represents the main direction of the development of the automobile suspension. Among them, the adjustable damping semi-active suspension can independently track the damping force demand signal, and the damping force can be continuously adjusted to any point in the damping working area, which can meet the vehicle performanc...

AI Technical Summary

Problems solved by technology

At present, the logic relationship between the working range of the damping force and the control force demand signal and the relative speed of the suspension is not directly considered in the control process of the semi-active suspension. The output force range and the relative speed of the suspension limit or impose constraints on it, resulting in the suspension not being able to obtain optimal control effects

Giorgetti N et al. transformed the constrained semi-active suspension control system into a piecewise affine system based on model predictive control theory, and solved it by mixed integer quadratic programming, but did not consider the nonlinear boundary constraints of the damping force of the shock absorber (Giorgetti N, Bemporad A, Tsengz H E, et al. Hybrid model predictive control application towards optimal semi-active suspension[J]. International Journal of Control, 2006, 79(5):391-398)

The patent document (CN105974821A) proposes a hybrid control method for vehicle semi-active suspension based on damping multi-mode switching shock absorbers. The restoration damping coefficient and compression damping coefficient of the shock absorber in different damping modes are determined through simulation analysis, and based on the hybrid The logic dynamic modeling method is used to design the hybrid model predictive controller of the semi-active suspension. The focus is on the multi-mode switching of the shock absorber damping, and it does not involve the performance of the semi-active suspension and the constraints that the damping force of the semi-active suspension must satisfy. question

Images