On the Stability of Nonlinear Wheel-Slip Zero Dynamics in Traction Control Systems

Abstract Traction control for vehicles with wheel individual drives is a challenging task, since the wheel slips are unknown when each wheel transfers a torque. This contribution presents an approach which deals with this problem especially for electrical vehicles, where the drive torques can be changed very fast in comparison to vehicles with combustion engines. The algorithm is based on two filters. The first filter is an adaptive Kalman filter which is used to detect fast changes in the stability conditions of the wheels. The filter also delivers a valuation for the torque to which the drive torque has to be reduced to get the wheel stable again. The second filter estimates the wheel slip. It is based on a simplified expression of the slip dynamics in combination with a special reset strategy for low slip situations. This filter allows detection of slow changes in the stability conditions. All filters are wheel individual and use only standard sensor information. No tire model is needed for the filters to work. A simple reflexive traction controller, which is based on a state machine, computes the drive torques in dependence on the stability criteria based on the filter outputs.

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TO THE STABILITY OF TANK VEHICLES IN THE BRAKE MODE

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2019-1-257-27-32 ◽

2019 ◽

pp. 27-32

Author(s):

Denys Popelysh ◽

Yurii Seluk ◽

Sergyi Tomchuk

Keyword(s):

Mathematical Model ◽

Control Systems ◽

Distribution Systems ◽

Traffic Accidents ◽

Road Traffic ◽

Center Of Mass ◽

Dynamic Processes ◽

Course Stability ◽

The Stability ◽

Tank Vehicles

This article discusses the question of the possibility of improving the roll stability of partially filled tank vehicles while braking. We consider the dangers associated with partially filled tank vehicles. We give examples of the severe consequences of road traffic accidents that have occurred with tank vehicles carrying dangerous goods. We conducted an analysis of the dynamic processes of fluid flow in the tank and their influence on the basic parameters of the stability of vehicle. When transporting a partially filled tank due to the comparability of the mass of the empty tank with the mass of the fluid being transported, the dynamic qualities of the vehicle change so that they differ significantly from the dynamic characteristics of other vehicles. Due to large displacements of the center of mass of cargo in the tank there are additional loads that act vehicle and significantly reduce the course stability and the drivability. We consider the dynamics of liquid sloshing in moving containers, and give examples of building a mechanical model of an oscillating fluid in a tank and a mathematical model of a vehicle with a tank. We also considered the method of improving the vehicle’s stability, which is based on the prediction of the moment of action and the nature of the dynamic processes of liquid cargo and the implementation of preventive actions by executive mechanisms. Modern automated control systems (anti-lock brake system, anti-slip control systems, stabilization systems, braking forces distribution systems, floor level systems, etc.) use a certain list of elements for collecting necessary parameters and actuators for their work. This gives the ability to influence the course stability properties without interfering with the design of the vehicle only by making changes to the software of these systems. Keywords: tank vehicle, roll stability, mathematical model, vehicle control systems.

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The Application of an Impedance-Passivity Controller in Haptic Stability Analysis

Applied Sciences ◽

10.3390/app11041618 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1618

Author(s):

Ping-Nan Chen ◽

Yung-Te Chen ◽

Hsin Hsiu ◽

Ruei-Jia Chen

Keyword(s):

Control Systems ◽

Force Feedback ◽

Training System ◽

Considerable Time ◽

Virtual Training ◽

Control Gain ◽

Negative Damping ◽

The Stability ◽

Time Required ◽

Stable Control

This paper proposes a passivity theorem on the basis of energy concepts to study the stability of force feedback in a virtual haptic system. An impedance-passivity controller (IPC) was designed from the two-port network perspective to improve the chief drawback of haptic systems, namely the considerable time required to reach stability if the equipment consumes energy slowly. The proposed IPC can be used to achieve stability through model parameter selection and to obtain control gain. In particular, haptic performance can be improved for extreme cases of high stiffness and negative damping. Furthermore, a virtual training system for one-degree-of-freedom sticking was developed to validate the experimental platform of our IPC. To ensure consistency in the experiment, we designed a specialized mechanical robot to replace human operation. Finally, compared with basic passivity control systems, our IPC could achieve stable control rapidly.

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The Daimler-Benz Winter Test Center “Rovaniemi” — A Prerequisite for Experimental Development of Electronic Wheel Slip Control Systems for Commercial Vehicles

10.4271/890038 ◽

1989 ◽

Cited By ~ 1

Author(s):

E. Göhring

Keyword(s):

Control Systems ◽

Commercial Vehicles ◽

Wheel Slip ◽

Experimental Development ◽

Slip Control

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Iterative stability analysis for general polynomial control systems

Nonlinear Dynamics ◽

10.1007/s11071-021-06768-7 ◽

2021 ◽

Author(s):

Bo Xiao ◽

Hak-Keung Lam ◽

Zhixiong Zhong

Keyword(s):

Stability Analysis ◽

Lyapunov Function ◽

Control Systems ◽

Polynomial System ◽

Stability Conditions ◽

General Polynomial ◽

Main Challenge ◽

Detailed Simulation ◽

Feasible Solutions ◽

The Stability

AbstractThe main challenge of the stability analysis for general polynomial control systems is that non-convex terms exist in the stability conditions, which hinders solving the stability conditions numerically. Most approaches in the literature impose constraints on the Lyapunov function candidates or the non-convex related terms to circumvent this problem. Motivated by this difficulty, in this paper, we confront the non-convex problem directly and present an iterative stability analysis to address the long-standing problem in general polynomial control systems. Different from the existing methods, no constraints are imposed on the polynomial Lyapunov function candidates. Therefore, the limitations on the Lyapunov function candidate and non-convex terms are eliminated from the proposed analysis, which makes the proposed method more general than the state-of-the-art. In the proposed approach, the stability for the general polynomial model is analyzed and the original non-convex stability conditions are developed. To solve the non-convex stability conditions through the sum-of-squares programming, the iterative stability analysis is presented. The feasible solutions are verified by the original non-convex stability conditions to guarantee the asymptotic stability of the general polynomial system. The detailed simulation example is provided to verify the effectiveness of the proposed approach. The simulation results show that the proposed approach is more capable to find feasible solutions for the general polynomial control systems when compared with the existing ones.

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