Investigation of an off-road vehicle equipped with magnetorheological dampers

Abstract

At present, owing predominantly to advances in measurement technology, microprocessor control and development of smart materials have witnessed a widespread adoption of semi-active damping systems based on magnetorheological fluid technology into everyday life. An important class of systems which utilize magnetorheological technology is constituted by vehicle vibration systems. These systems are generally equipped with different numbers of reciprocating or rotary dampers filled with magnetorheological fluid. Dampers and their properties are controlled by an electronic controller with embedded control algorithm. In this article, a simplified model of an off-road vehicle equipped with a realtime controlled semi-active suspension system with magnetorheological dampers is presented. In addition, a simple algorithm employed to control them is described. Algorithm efficacy has been verified by means of conducting numerous road and off-road experiments employing Honker 2000 vehicle. The main goal of this article is to present simplified yet efficient methods for controlling changes in properties of suspension of an off-road vehicle with magnetorheological dampers. These properties are controlled by an optimization algorithm responsible for an optimal selection of friction in magnetorheological dampers. The algorithm allows for a substantial improvement of the performance of an off-road vehicle suspension.

Improvement of ride quality for patient lying in ambulance with a new hydro-pneumatic suspension

“…It indicates that for ADVs, the effects of the cross-sectional areas on the damping characteristic are the same with the effects on the additional stiffness characteristic. (22) and (23) indicates that both PHDVs and PRDVs can generate the additional vertical, pitch, and roll motion damping for sprung mass. The motion between the vertical and pitch are coupled by area ratio factor À2(ah f i m 2 À bh r i ).…”

“…Semi-active and active suspensions have been adopted to improve overall dynamic performance for both handling and ride comfort, [18][19][20][21] while the passive suspensions are still widely used due to inevitable limits of these semi-active/active suspensions, such as increased cost, uncertain reliability, power consumption, and inherent complexity. 22 , 23 The conventional suspension (CS) with anti-roll bars (ARBs) can improve the roll stability, while the ride comfort would be deteriorated as well. 24 Some advanced passive suspension systems also have been reported to enhance overall performance for both handling and ride comfort.…”

Prototype of a controllable damper based on granular materials subjected to partial vacuum

“…The idea of designing a prototype of a granular damper with controlled dissipative properties was taken from the authors previous experience gained during research on MR dampers. Although MR fluids are one of the more commercialized intelligent materials, their use in engineering applications still poses some difficulties [11]. They can be divided into two main groups: technological and material.…”

“…In the group of technological problems one should mention the selection of appropriate construction materials for a given MR device, which physical characteristics must meet strictly defined assumptions. Magnetorheological fluids change their properties under the influence of an externally applied magnetic field [11]. Materials used for the construction of devices working on their basis should provide, among others the possibility of eliminating the phenomenon of residual magnetism -characteristic of many metals commonly used in machine designing.…”

Identification-based predictive control of semi-active shock-absorbers for adaptive dynamic excitation mitigation

“…Large variety of shockabsorbers' applications leads to numerous technical solutions, which differ from each other in terms of construction, involved physical phenomena and complexity of control system. At present, more and more frequent practice is the use of so-called smart devices, which are based on functional materials and advanced control systems, e.g., magneto-rheological energy absorbers [12][13][14][15], electro-rheological dampers [16,17], particle impact dampers [18,19], or pneumatic adaptive absorbers with piezoelectric valves [20]. Simultaneously, advances in the development of…”