Muhammad Zahir Hassan

The Exploration of Autonomous Vehicle Driving Styles: Preferred Longitudinal, Lateral, and Vertical Accelerations

This paper describes a new approach in exploring preferred driving styles for autonomous vehicles through simulation of autonomous driving in real road conditions. A Wizard experiment with an equipped car was conducted to investigate the preferences of people with different driving styles, assertive and defensive, for three autonomous vehicle driving styles (defensive, assertive and light rail transit), inducing different acceleration forces, at three different road profiles. Subjective and objective measurements were collected. The results show that the defensive driving style was preferred and there were variations between participants related to their own driving style. The results indicate that the preferences of assertive drivers for the driving style of an autonomous vehicle may not match their own driving style. Yet, users of future autonomous vehicles should be able to indicate and adjust the driving behaviour of an autonomous vehicle to their own preferences in order to maximize comfort in travelling experience.

The evaluation of disc brake squeal propensity through a fully coupled transient thermomechanical model

This paper presents a fully coupled transient thermomechanical analysis of a disc brake that takes into account the so-called ‘rotating-heat-source’ effect. Results from this are used to inform the time-based extraction of system eigenvalues that permit quantification of the squeal propensity of the brake. The model performance is validated against a series of dynamometer tests, based upon the SAE J2521 drag brake test schedule, in which the ability of the model to predict the fugitive nature of the squeal problem is confirmed. Finally, a parametric study is also presented that shows how the technique can be used to desensitise the squeal propensity to both material and geometric design changes.

Position tracking of automatic rack and pinion steering linkage system through hardware in the loop testing

Vehicle handling behavior is much influenced by the performance of steering system and its mechanism. Steering linkage play a very important role in maneuvering of a vehicle. In this paper, a set of kinematic relations of rack and pinion steering linkage system are modeled in MATLAB Simulink environment based on kinematic model equations is presented to study the relationship between steering wheel and tire angle. A Hardware-in-the-loop Simulations (HILS) test rig with actual rack and pinion mechanism has been set up using real time software environment from MathWorks namely xPC Target, LVDT and encoder sensors installed for data measurement at various steering angle. Results from simulation model demonstrate a linear pattern occurred from maximum lock-to-lock steering wheel angle and it is closely follow the sine input trend through HILS experiment with acceptable error.

Development of Antilock Braking System Based on Various Intelligent Control System

This paper presents about the development of an Antilock Braking System (ABS) using quarter vehicle model and control the ABS using different type of controllers. Antilock braking system (ABS) is an important part in vehicle system to produce additional safety for drivers. In general, Antilock braking systems have been developed to reduce tendency for wheel lock and improve vehicle control during sudden braking especially on slippery road surfaces. In this paper, a variable structure controller has been designed to deal with the strong nonlinearity in the design of ABS controller. The controllers such as PID used as the inner loop controller and Fuzzy Logic as outer loop controller to develop as ABS model to control the stopping distance and longitudinal slip of the wheel.

UTeM`s Amphibious Hybrid Vehicle: Ride and Handling Analysis

The vehicle ride and handling analysis is one of the important aspects in vehicle dynamics. This paper takes a model of amphibious vehicle to establish the exact virtual behavior of vehicles riding and handling base on the virtual design parameter. This vehicle can operate both on ground and water, therefore the analysis model is developed using seven degree of freedom model for ground operation and one degree of freedom model for water operation. The seven DOF are moment of roll, pitch, yaw and all four tires motion while the rest is buoyancy. Therefore, the ability and limitation of the vehicle demonstrate the behavior of unexpected case happened. These facts in turn to be used to improve the ride and handling level during acceleration, deceleration, cornering and step steer. The model also capable to function on the water where as the design of the body work considers the buoyancy concept for stability on every condition of wave surface. The analysis of buoyancy and stability for this model shows the vehicle ability to perform in the state of equilibrium condition under heeling and capsizing on water surface.

An Analytical Model to Identify Brake System Vibration within the Low Frequency Domain

This paper presents the analytical model of a brake system to investigate the low frequency vibration. The purpose of this study is to model and validate brake system vibration. The brake model was developed by applying the theory of sinusoidal traveling waves and wave super positioning. An experimental modal analysis (EMA) of the brake disc has been carried out to obtain the natural frequencies. Wave equations were then formulated based on the experimental data. These waves are super positioned to be shown as a single spatial and temporal function that will provide periodic excitation to the brake pad. The brake pad was modeled as a beam element with distributed friction force. The differential equations were solved using Greens dynamic formulation. The model is capable of predicting vibration behavior of the brake pad for whole range below 1 kHz which has shown strong agreement with the experimental results validated through in-house brake dynamometer. This brake model can serve as a tool to investigate the relationship between braking parameters and other variables within the brake system.

Design of Chassis Frame for All-Terrain Vehicle for Educational Purposes

All-terrain vehicle is famously used for various purposes. The design of the chassis of this vehicle is critical in determining the overall strength. In this paper, the design chassis frame for the use of all-terrain vehicle (ATV) is presented. In designing the chassis frame, a proper design method was employed. Finite Element Analysis (FEA) was utilized to determine the maximum stress and displacement of the frame when a particular load is applied onto it. Structure modifications need to be done if the chassis frame could not sustain the applied load. After the design process is completed, the fabrication of the frame is conducted by students of the engineering faculty. The fabricated frame will be used as the main part for a project of which a complete ATV will be developed. The main purpose of the project is to instill the interest among the student in engineering through the application of classroom.

Finite Element Analysis on Brake Disc of an Educational All-Terrain-Vehicle

All-terrain vehicle is famously used for various purposes such as in civilian and military. The use of finite element analysis in a preliminary design stage has been demonstrated to be cost and time effective. In this paper, the finite element analysis of a brake disc for All-Terrain-Vehicle (ATV) is demonstrated. Eulerian-Lagrangian method was employed in this work where simple annular ring was used as the disc model. This study is limited to thermal and contact analysis between the disc and brake pad. The results in term of temperature and stresses distribution is obtained and presented. Moreover, the lateral displacement of the disc due to the friction contact is also shown. These results are then used to as a technical guideline in designing brake system for a fully customized ATV

Development of Vehicle Blind Spot System for Passenger Car

Blind spot of a passenger car is an area around the vehicle that cannot be seen while looking either forward or through side or rear view mirror. In this paper, a blind spot system known as ZRT Vehicle Blind Spot System (ZRT-VBSS) has been developed using Arduino and ultrasonic sensors to overcome the problem. The system is capable to detect a moving vehicle in blind spot area under three main condition of which static, dynamic speed operation at 60 and 100 km/h and also overtake position. The results from the experimental investigation show that ZRT-VBSS is capable to perform at various operating condition that make it reliable to provide solution for driver to overcome the blind spot phenomenon.

A Parallel Study of Vibration Analysis and Acoustic Analysis in Low Frequency Brake Noise

An acoustic analysis in the investigation of brake noise shows the severity of the noise and its characteristics and a vibration analysis shows the excitations of noise that is present in the braking event. In this study, vibration and acoustic analyses were used to study the brake noise which is produced during braking. Vibration and acoustic data were collected simultaneously during braking to identify the braking condition. The data analysis focuses on the low frequency domain. The Fast Fourier method was used to analyse the vibration and acoustic signals. The computation of FFT was done independently and the frequency domains obtained were compared. The parallelism in the analysis was used to identify the acoustic source. The determination of the source will aid in brake noise reduction efforts and reinforce the vibration analysis method as a system identification method for brake noise.