# Dynamic response force control of electrohydraulic servo actuator of active suspension based on intelligent optimization algorithm

## TL;DR

This paper introduces a new control method for car suspensions that improves performance and comfort using an advanced optimization algorithm.

## Contribution

The novel contribution is the use of a multi-strategy improved beluga whale optimization algorithm to optimize a fractional-order PID controller for electrohydraulic actuators.

## Key findings

- The MSIBWO-FOPID controller reduces rise time and RMSE by 66.7% and 70.3%, respectively, compared to BWO-FOPID for step inputs.
- Under random road excitation, the controller reduces vertical acceleration RMSE by 51.7% compared to passive suspension.
- The controller shows improved disturbance rejection and precision for sine inputs.

## Abstract

Traditional PID control faces challenges in addressing parameter uncertainty and nonlinearity in active suspension electrohydraulic servo actuators, leading to suboptimal performance. To address these challenges, a fractional-order PID (FOPID) controller optimization method based on the Multi-Strategy Improved Beluga Whale Optimization (MSIBWO) algorithm is proposed. Simulation results in MATLAB/Simulink demonstrate that the MSIBWO-FOPID controller significantly outperforms traditional PID and BWO-FOPID controllers in force tracking and robustness. For step input, the rise time and the root mean square error(RMSE) are reduced by 66.7% and 70.3%, respectively, compared to BWO-FOPID. For sine inputs, the system achieves better disturbance rejection and higher precision. Using a half-car model, the MSIBWO-FOPID controller improves ride comfort significantly. Under random road excitation, the RMSE values of the vehicle body’s vertical acceleration and pitch angle acceleration are reduced by 51.7% and 13.1%, respectively, compared to passive suspension, outperforming both PID and BWO-FOPID controllers.