Disturbance observer based sliding mode control of active suspension systems

This study investigates adaptive neural network (NN) state feedback control and robust observation for an active suspension system that considers parametric uncertainties, road disturbances and actuator saturation. An adaptive radial basis function neural network is adopted to approximate uncertain non-linear functions in the dynamic system. An auxiliary system is designed and presented to deal with the effects of actuator saturation. In addition, since it is difficult to obtain accurate states in practice, an NN observer is developed to provide state estimation using the measured input and output data of the system. The state observer-based feedback control parameters with saturated inputs are optimised by the particle swarm optimisation scheme. Furthermore, the uniformly ultimately boundedness of all the closed-loop signals is guaranteed through rigorous Lyapunov analysis. The simulation results further demonstrate that the proposed controller can effectively suppress car body vibrations and offers superior control performance despite the existence of non-linear dynamics and control input constraints.

https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/iet-cta.2015.1317

Adaptive neural network control for active suspension system with actuator saturation

In this paper, an active suspension system employing a new nonlinear control law is proposed to address the problem of achieving the dual objective of providing ride comfort and trying to keep the suspension deflection within the constraint of rattle space. The control is a nonlinear function of the magnitude of the suspension deflection and an estimate of the effect of the road disturbance. The control scheme is analyzed and assessed for the large classes of road profiles through simulation and by experimentation on a laboratory setup. The performance of the proposed scheme is compared with a passive suspension system.

Nonlinear Control for Dual Objective Active Suspension Systems

The applications of energy regeneration and conversion technologies based on hydraulic transmission systems: A review

This study proposes a modified energy-saving skyhook consisting of active control, energy regeneration, and switch. The modified skyhook coordinates the contradiction between dynamic performance an...

https://journals.sagepub.com/doi/pdf/10.1177/1077546318775508

A modified energy-saving skyhook for active suspension based on a hybrid electromagnetic actuator:

Probe into Necessity of Active Suspension Based on LQG Control

New reclaiming energy suspension and its working principle

The objective of this research is to propose a new and practical LQG control method for the vehicle active suspension. The novelty lies in optimizing the LQG controller without road input signal for the active suspension to improve practicability of LQG control method. Taking a quarter-vehicle model as an example, the control parameters of LQG controller without road input signal for the active suspension are optimized based on genetic algorithm (GA) with the suspension quadratic performance index taken as the fitness function. Comparative simulations show the optimized LQG controller proposed can achieve a better comprehensive performance and is more practical than the normal LQG one for the active suspension.

Optimal Design of Active Suspension Based on LQG Control without Road Input Signal

The invention discloses a magnetic track breaker with the composite working of a permanent magnet and an electromagnet. A rotating shaft comprises two half shafts and a second permanent magnet, wherein the two half shafts made of permeability magnetic materials are arranged oppositely; a through groove which runs through in an axial direction is formed at the middle of the two half shafts; the second permanent magnet of which the size is accordant with the size of the through groove is embedded inside the through groove; a bracket structure comprises side plates which are made of permeability magnetic materials and are positioned at the front and rear sides and a middle isolating plate which is fixedly connected with the two side plates and is made of non-permeability magnetic materials; the rotating shaft is arranged below the middle isolating plate; a groove which runs through the axial direction is formed between the two side plates and the part above the middle isolating plate; a first permanent magnet of which the size is accordant with the size of the groove is put into the\ groove; coils are correspondingly sleeved at circles of the upper parts of the side plates at two sides; and pole shoes are connected with the lower parts of the side plates. The backward torque of the rotating shaft while rotating is effectively reduced by controlling the currents and the directions of the coils; and after the magnetic track breaker works stably, the current is cut off; when an extra brake force is needed, the mode of composite brake of the electromagnet and the permanent magnet is adopted, so that the brake effect is further enhanced.

Magnetic track breaker with composite working of permanent magnet and electromagnet

This research presents systematically an optimal design for the suspension based on LQG control to improve vehicle ride comfort and reduce manufacturing & using costs. The novelty lies in revealing that the optimized LQG control suspension is just a semi-active one. Based on quarter-vehicle model, investigation to the influences of suspension stiffness & basal damp on suspension performance and global damping characteristics of control force shows that the performance of LQG control active suspension is nothing to do with suspension stiffness & basal damp and the global damping characteristics of control force becomes obviously negative from obviously positive with basal damp increasing regardless of suspension stiffness. Suspension performance and manufacturing & using costs are considered comprehensively during optimizing the LQG control suspension. The optimization result shows that the optimized semi-active suspension based on LQG control has excellent comfort ride and low manufacturing & using costs.

Shian Chen

Papers

Probe into Necessity of Active Suspension Based on LQG Control

New reclaiming energy suspension and its working principle

Optimal Design of Active Suspension Based on LQG Control without Road Input Signal

Magnetic track breaker with composite working of permanent magnet and electromagnet

An optimal design for suspension based on LQG control