Instrumented Experimental Vehicle Research Articles

On tyre force virtual sensing for future Automated Vehicle-Based Objective Tyre Testing (AVBOTT)

ABSTRACTIn this paper, a novel Automated Vehicle-Based Objective Tyre Testing (AVBOTT) concept is introduced. In brief, AVBOTT pursues the development of inexpensive automated testing vehicles capable of executing a set of standardised manoeuvres and generate large amounts of tyre data rapidly and inexpensively. Naturally, the costs associated with current vehicle instrumentation and, in particular, with Wheel Force Transducers (WFT) prevent this concept from realisation at the moment. In order to overcome this limitation, a cost-effective alternative to WFT is proposed in this paper to estimate the tyre forces using indirect measurement techniques. Specifically, for the first time, the validity of random-walk virtual tyre force sensors for vehicle-based objective tyre testing is studied comprehensively. Moreover, the suitability of Adaptive Neuro-Fuzzy Inference Systems (ANFIS) to extract relevant tyre attributes in a systematic manner from lateral and longitudinal dynamics manoeuvres is analysed in detail. The proposed solutions are assessed in a complete tarmac tyre testing program carried out at IDIADA with a fully instrumented experimental vehicle. Additional winter testing activities performed at Revi facilities (Sweden) complete the experimental evaluation at different mu levels.

Validation of Vehicle Model Response with an Instrumented Experimental Vehicle

A steering aid system called active steering is evaluated by simulating different kinds of driving events. The main purpose of the steering system is to allow the driver control the vehicle independently. A full car vehicle model is simulated in Matlab/Simulink with 14 degree of freedom of equations which include the ride vehicle model and also the handling model. The steering angle is the input of the vehicle model that should be focused on. The angle of the steering system between the tires when turning the vehicle is taken in consideration. Simulations are made on different road conditions effect and also side wind disturbances. Different values are applied to the simulation to reduce the effect of the driving events. Therefore, these simulations results to provide a better improvement to the steering system. The aim for this work is to validate the vehicle response with an instrumented experiemental vehicle. Specific driving events in these simulations are the road adhesions and lateral side wind disturbances.

Using Modelling and Simulation to Predict Dynamics of Converted Ground Vehicle

In order to redesign and convert the passenger ground vehicle Land Rover defender 110 into military vehicle for different surveillance and reconnaissance missions it is necessary, prior to equipment integration, to assess its future dynamic response. For this purpose, the 19-degree of freedom multibody simulation model of the defender was developed using the software package MSC.ADAMS/Car. The simulation model was validated using the instrumented experimental vehicle for two scenarios namely bump test and double lane change manoeuver. Comparison of numerical predictions suggests reasonably good agreement with the actual vehicle responses. The validated model was then used to assess the effect of longitudinal and vertical position of the added equipment on the responses of the upgraded vehicle. Lateral stability degradation due to the added equipment was also investigated defining the rollover threshold as an objective assessment criterion. The obtained results show considerable lateral stability degradation for both marching and operating heights of the added equipment.<br /><p style="margin-bottom: 0.08in; line-height: 100%;" align="justify"><span style="font-family: Times New Roman,serif;"><span style="font-size: medium;"><br style="font-size: medium;" /></span></span></p>

Dynamic vehicle model for handling performance using experimental data

An analytical vehicle model is essential for the development of vehicle design and performance. Various vehicle models have different complexities, assumptions and limitations depending on the type of vehicle analysis. An accurate full vehicle model is essential in representing the behaviour of the vehicle in order to estimate vehicle dynamic system performance such as ride comfort and handling. An experimental vehicle model is developed in this article, which employs experimental kinematic and compliance data measured between the wheel and chassis. From these data, a vehicle model, which includes dynamic effects due to vehicle geometry changes, has been developed. The experimental vehicle model was validated using an instrumented experimental vehicle and data such as a step change steering input. This article shows a process to develop and validate an experimental vehicle model to enhance the accuracy of handling performance, which comes from precise suspension model measured by experimental data of a vehicle. The experimental force data obtained from a suspension parameter measuring device are employed for a precise modelling of the steering and handling response. The steering system is modelled by a lumped model, with stiffness coefficients defined and identified by comparing steering stiffness obtained by the measured data. The outputs, specifically the yaw rate and lateral acceleration of the vehicle, are verified by experimental results.

Study on the potential application of electronic wedge brake for vehicle brake system

This paper presents a study of the potential application of an electronic wedge brake for vehicle brake system using human-in-the-loop simulation. Simulation was made in MATLAB Simulink software which interfaces an imaginary vehicle with a real time input from a human, such as throttle and brake input. The imaginary vehicle model that is used is a vehicle dynamic model that has been validated experimentally using an instrumented experimental vehicle. A validated electronic wedge brake actuator model was then used as the brake actuator model where a suitable control strategy, namely proportional-integral-derivative and proportional-integral controllers, was utilised as the force and gapping control respectively. To verify the effectiveness of the proposed actuator in a vehicle, the simulation results are compared with the results of human-in-the-loop simulation of a vehicle using a conventional hydraulic brake and the response of the experimental vehicle using the same dynamic test, namely the sudden braking test. The simulation results show that the proposed simulation method and actuator with appropriate controller strategy have similar behaviour to a hydraulic brake in terms of its capability to produce the desired braking force to reduce the speed and halt the vehicle. The outcomes from this study can be considered in design optimisation and implementation in a real vehicle.

MODELLING AND VALIDATION OF THE VEHICLE LONGITUDINAL MODEL

This paper presents the detailed derivation and validation of a full vehicle model to study the behaviour of vehicle dynamics in the longitudinal direction. The model consists of handling and tyre subsystems, an engine model subsystem, an automatic transmission subsystem and a brake model subsystem. The full vehicle model was then validated using an instrumented experimental vehicle based on the driver input from brake and throttle pedals. Vehicle transient handling dynamic tests known as sudden braking tests were performed for the purpose of validation. Several behaviours of the vehicle dynamics were observed during braking and throttling manoeuvres, such as body longitudinal velocity, wheel linear velocity and tyre longitudinal slip, at each quarter of the vehicle. Comparisons of the experimental results and model responses with sudden braking and throttling imposed motions were made in this study. It is concluded that the trends between simulation results and experimental data were found to be almost similar with an acceptable level of error for the application at hand.

Modeling and Validation of Quarter Vehicle Traction Model

This manuscript provides modeling and validation of a quarter car vehicle model to study the wheel dynamics behavior in longitudinal direction. The model is consists of a longitudinal slip model subsystem, a quarter body dynamic and tire subsystems. The quarter vehicle model was then validated using an instrumented experimental vehicle based on the driver input from brake and throttle pedals. Vehicle transient handling dynamic tests known as sudden braking test was performed for the purpose of validation. Several behaviors of the vehicle dynamics were observed during braking maneuvers such as body longitudinal velocity, wheel linear velocity and tire longitudinal slip at a quarter of the vehicle. Comparisons of the experimental results and model responses with sudden braking imposed motions were made. Consequently, the trends between simulation results and experimental data were found almost similar with an acceptable level of error for the application at hand.

Simulation and experimental evaluations on the performance of pneumatically actuated active roll control suspension system for improving vehicle lateral dynamics performance

This paper presents the derivation of a full vehicle model which consists of ride, handling and tyre subsystems to study vehicle dynamics behaviour in the lateral direction. The full vehicle model is then validated experimentally using an instrumented experimental vehicle based on steering wheel input from the driver. Three types of vehicle dynamics test were performed for model validation, namely step steer, slalom and double lane change tests. The validation results show that the behaviours of the model are similar to the real vehicle with acceptable error. An Active Roll Control (ARC) suspension system was developed using the validated full vehicle model to reduce unwanted vehicle motions during steering input manoeuvres such as body roll angle, body roll rate, vertical acceleration of the body and body heave. The proposed controller for the ARC system is a combination of Proportional-Integral-Derivative (PID) control with roll moment rejection loop. The results of the study show that the proposed control structure significantly improves the dynamics performance of the vehicle during step steer, slalom and double lane change manoeuvres compared with a passive vehicle system. The additional roll moment rejection loop is found to be able to further improve the performance of the PID ARC system. The effectiveness of the ARC system with the proposed control was also proven experimentally using the instrumented experimental vehicle.

Modelling, validation and adaptive PID control with pitch moment rejection of active suspension system for reducing unwanted vehicle motion in longitudinal direction

This paper provides a detailed derivation of a full vehicle model, which may be used to simulate the behaviour of a vehicle in longitudinal direction. The 14 degrees of freedom (14-DOF) vehicle model is integrated with an analytical tyre dynamics using Calspan tyre model. The full vehicle model was validated experimentally with an instrumented experimental vehicle based on the driver input from brake or throttle pedals. Several transient handling tests were performed, namely sudden acceleration and sudden braking test. Comparisons of the experimental result and model response with sudden braking and throttling imposed motion are made. The results of model validation show that the trends between simulation results and experimental data are almost similar with acceptable error. An adaptive PID control strategy was implemented on the validated full vehicle model to reduce unwanted vehicle motions in longitudinal direction during sudden braking and throttling manoeuvre. The results show that the proposed control structure is able to significantly improve the dynamic performance of the vehicle during sudden braking and sudden acceleration under various conditions.

Modelling, validation and roll moment rejection control of pneumatically actuated active roll control for improving vehicle lateral dynamics performance

This paper presents a detailed derivation of a full vehicle model and validation using an instrumented experimental vehicle. Two types of vehicle dynamics test are performed for the purpose of model validation namely step steer test and double lane change test. The results of model validation show that the behaviours of the model closely follow the behaviour of a real vehicle. An active roll control (ARC) suspension system is then developed on the validated full vehicle model to reduce unwanted vehicle motions during cornering manoeuvres. The proposed controller structure for the ARC system is PID control with roll moment rejection loop. The results of the study show that the proposed control structure is able to significantly improve the dynamics performance of the vehicle compared to the passive vehicle system. The additional roll moment rejection loop is able to further improve the performance of the PID controller for the ARC system.

Gain scheduling PID control with pitch moment rejection for reducing vehicle dive and squat

This paper presents a derivation of a full vehicle model to study vehicle dynamics behaviour in longitudinal direction. The full vehicle model is then validated using an instrumented experimental vehicle based on the driver input from brake and throttle pedals. Two tests are performed for the purpose of model validation, namely, sudden braking and sudden acceleration test. The results of the validation show that the behaviours of the model closely follow the behaviour of a real vehicle. An active suspension control system is then developed on the validated full vehicle model to reduce unwanted vehicle motions during braking and throttling manoeuvres. The proposed controller structure for the active suspension system is gain scheduling PID control with pitch moment rejection loop. The results show that the proposed control structure is able to significantly improve the dynamic performance of the vehicle during sudden braking and sudden acceleration under various conditions.