A Double Sky-Hook Algorithm for Improving Road-Holding Property in Semi-Active Suspension Systems for Application to In-Wheel Motor

This paper presents a double sky-hook algorithm for controlling semi-active suspension systems in order to improve road-holding property for application in an in-wheel motor. The main disadvantage of the in-wheel motor is the increase in unsprung masses, which increases after shaking of the wheel, so it has poor road-holding that the conventional theoretical sky-hook algorithm cannot achieve. The double sky-hook algorithm uses a combination of damper coefficients, one from the chassis motion and the other from the wheel motion. Computer simulations using a quarter and full car dynamic models with the road conditions specified by ISO2631 showed the effectiveness of the algorithm. It was observed that the algorithm was the most effective in the vicinity of the wheel hop frequency. This paper also proposed the parameter set of the double sky-hook algorithm to differentiate the driving mode of vehicles under advanced development.

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Influence of the road profile accuracy on disturbance compensation in active suspension systems

at - Automatisierungstechnik ◽

10.1515/auto-2020-0116 ◽

2021 ◽

Vol 69 (6) ◽

pp. 485-498

Author(s):

Felix Anhalt ◽

Boris Lohmann

Keyword(s):

Ride Comfort ◽

Feedforward Control ◽

Active Suspension ◽

Disturbance Compensation ◽

Critical Factors ◽

The Road ◽

Suspension Systems ◽

Active Suspension Systems ◽

Road Profile ◽

Profile Accuracy

Abstract By applying disturbance feedforward control in active suspension systems, knowledge of the road profile can be used to increase ride comfort and safety. As the assumed road profile will never match the real one perfectly, we examine the performance of different disturbance compensators under various deteriorations of the assumed road profile using both synthetic and measured profiles and two quarter vehicle models of different complexity. While a generally valid statement on the maximum tolerable deterioration cannot be made, we identify particularly critical factors and derive recommendations for practical use.

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An adaptive control approach for semi-active suspension systems under unknown road disturbance input using hardware-in-the-loop simulation

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331219895935 ◽

2020 ◽

pp. 014233121989593 ◽

Cited By ~ 1

Author(s):

Gokhan Kararsiz ◽

Mahmut Paksoy ◽

Muzaffer Metin ◽

Halil Ibrahim Basturk

Keyword(s):

Adaptive Control ◽

Control Method ◽

Active Suspension ◽

Magnetorheological Damper ◽

Hardware In The Loop ◽

Control Approach ◽

The Road ◽

Suspension Systems ◽

Active Suspension Systems ◽

Road Disturbance

This article presents an application of the adaptive control method to semi-active suspension systems in the presence of unknown disturbance and parametric uncertainty. Due to the technical difficulties such as time delay and sensor noise, the road disturbance is assumed to be unmeasured. To overcome this problem, an observer is designed to estimate the disturbance. It is considered that the road profile consists of a finite number of the sum of sinusoidal signals with unknown amplitudes, phases and frequencies. After the parametrization of the observer, the adaptive control approach is employed to attenuate the effect of the road-induced vibrations using a magnetorheological damper. It is proved that the closed-loop system is stable, despite the adverse road conditions. Finally, the performance of the controller is illustrated with a hardware-in-the-loop simulation in which the system is subjected to sinusoidal and random profile road excitations. To demonstrate the benefits of the adaptive controller, the results are presented in comparison with a conventional proportional integral derivative (PID) controller.

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Road-Holding-Oriented Control and Analysis of Semi-Active Suspension Systems

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4043764 ◽

2019 ◽

Vol 141 (10) ◽

Cited By ~ 3

Author(s):

Zhengkai Li ◽

Weichao Sun ◽

Huijun Gao

Keyword(s):

Active Suspension ◽

Vehicle Suspension ◽

The Road ◽

Suspension Systems ◽

Mixed Control ◽

Active Suspension Systems ◽

Predictive Controller ◽

Working Principle ◽

On The Road ◽

Vehicle Suspension System

The most important function of a vehicle suspension system is keeping the tires on the road surface, imposing requirements on the road-holding performance. As is well known, a semi-active suspension can improve road-holding performance, but little effort has been made to build road-holding-oriented semi-active suspension controllers (RHSAC). This study improved four model reference controllers (MRCs) as RHSAC, including the road-Hook (RH), inverse ground-Hook (IGH), sky-Hook (SH), and ground-Hook (GH). These MRCs have optimal performances in different frequency ranges, and their working principle is analyzed from an energy perspective. To combine the advantages of different MRCs, a mixed control strategy is proposed to enhance the road-holding performance of the MRCs. By mixing SH and RH, the mixed SH–RH performs almost as well as a finely tuned model predictive controller, which outperforms any single MRCs. Based on CarSim-matlab cosimulations, the effectiveness of the mixed RHSAC controller is verified by various real road tests.

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Research on Optimal Control and Simulation for Active Suspension Systems

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.340.631 ◽

2013 ◽

Vol 340 ◽

pp. 631-635

Author(s):

Yong Fa Qin ◽

Jie Hua ◽

Long Wei Geng

Keyword(s):

Optimal Control ◽

Ride Comfort ◽

Mathematic Model ◽

Active Suspension ◽

Suspension System ◽

Vehicle Body ◽

Vertical Acceleration ◽

The Road ◽

Suspension Systems ◽

Active Suspension Systems

Vehicles with active suspension systems become more ride comfort and maneuverable stability, many types of active suspensions have been applied to passenger vehicles, but one of the shortcomings of an active susupension system is that the additional control power consumption is needed. The core issues of designing an active suspension system are to minimiaze vibration magnitute and control energy comsuption of the active suspension system. A new mathematic model for an active suspension system is established based on vehicle dynamics and modern control theory. An optimal control law is constructed through solving the Riccati equation, and then the transfer function is deduced to describe the relationship between the vetical velosity of the road roughness and the output of suspension system. Three typical parameters of vehicle ride comfort are researched, such as vertical acceleration of vehicle body, dynamic deflection of suspension system and dynamic deformation of tires. A case of a quarter vehicle model is studied by simulation to show that the proposed method of modeling and designing optimal controller are suitable to develop active suspension systems.

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Incremental Model Predictive Control of Active Suspensions With Estimated Road Preview Information From a Lead Vehicle

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4047962 ◽

2020 ◽

Vol 142 (12) ◽

Author(s):

Siyang Song ◽

Junmin Wang

Keyword(s):

Model Predictive Control ◽

Predictive Control ◽

Heavy Traffic ◽

Active Suspension ◽

The Road ◽

Suspension Systems ◽

Incremental Model ◽

Active Suspension Systems ◽

Road Profile ◽

Lead Vehicle

Abstract In preview-based vehicle suspension applications, the preview of the road profile is highly dependent on the preview sensors. In some scenarios such as heavy traffic situations, the preview of road profile can only be estimated by other vehicles because the view of the preview sensors may be blocked by other vehicles. The estimated preview road information can contain errors, which thus requires the controller to have a good robust performance. In this paper, an incremental model predictive control (MPC) strategy for active suspension systems along with a road profile estimator using preview information from a lead vehicle is proposed. The efficacy of the proposed strategy is experimentally validated on two scaled-down active suspension stations with comparison to two conventional active suspension control approaches.

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A review of the vehicle suspension system

Journal of Mechanical and Energy Engineering ◽

10.30464/jmee.2020.4.2.109 ◽

2020 ◽

Vol 4 (2) ◽

pp. 109-114

Author(s):

Iyasu T. Jiregna ◽

Goftila Sirata

Keyword(s):

Active Suspension ◽

Suspension System ◽

The Body ◽

Vehicle Body ◽

Vehicle Suspension ◽

The Road ◽

Suspension Systems ◽

Active Suspension Systems ◽

Different Types ◽

Proper Design

The driving comfort of the vehicle is primarily determined by the design of the suspension system, which transmits the force between the vehicle and the ground. There are different types of vehicle suspension systems, including active suspension systems that provide significant benefits for ride comfort while driving. However, the existing active suspension systems have limited functions such as power, and also complex structure. To overcome the problem, the proper design of the active suspension system by considering its present limitations is essential. A well-designed active suspension system controls the load on the wheels under the resonance of the body structure and ensures driving comfort. It reduces the vibrational energy of the vehicle body caused by the excitation of the road while keeping the stability of the vehicle within an acceptable limit. For a proper design of the active suspension system, the road surface, the seat suspension, and the wheel load are the most important elements to consider. In this study, different types of vehicle suspension systems with their limitations have been thoroughly investigated. Many aspects of control and some of the essential practical considerations are also explored.

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