Abstract. This project is mainly about the dynamic modelling and parameter estimation of Unmanned Air Cushion Vehicle (UACV). The purpose of developing mathematical model of the Unmanned Air Cushion Vehicle (UACV) is due to its under actuated nonlinearities where it has less input compared to the output required. This system able to maneuver over land, water and other surfaces either at certain speed or maintain at a stationary position. In order to model the UACV, the system is set to have two propellers which are responsible to lift the vehicle by forcing high pressure air under the system. The air inflates the "skirt" under the vehicle, causing it to rise above the surface while another two propellers are used to steer the UACV forward. UACV system can be considered as under actuated since it possess fewer controller inputs that its degree of freedom. The system's motions are defined by the six degrees of freedom which are; heaved, sway and surge. Another three components are rotational motions which can be elaborated as roll, pitch and yaw. The problem related to UACV is normally related to obtaining accurate parameters of the system to be included into the mathematical model of the system. This is due to the body inertia of the system during the static and moving condition. Besides, the air that flows into the UACV skirt to create the cushion causes imbalance and will affect the system stability and controllability. In this research, UACV need to be mathematically modelled using Euler-Lagrange method. Then, parameters of the system can be obtained through direct calculation and Solidworks software. The parameters acquired are compared and verified using simulation and experimental studies.

Abstract

This paper highlights the development and vibration analysis of a four wheel vehicle chassis for single driver. A chassis is developed and proved to have a strong structure and minimized vibration. First, this project is concentrating on determining the static stress and strain concentrated on the chassis structure as well as determining the resultant displacement of the chassis frame with applied load exerted on the chassis. This is vital because the chassis acts as the main frame of the vehicle that subjected to stress, strain and vibration during the vehicle moves. Second, this project is also focussing on the developing a chassis structure for a four wheel vehicle for single driver system with a minimum vibration since vibration could cause the efficiency and the performance of a vehicle to drop. In this paper, the results obtained from the static test conducted on the basic chassis frame structure designed by using Solidworks software are presented as well as the fabricated basic chassis frame structure. The three dimensional modelling chassis frame structure is designed using Solidworks software and the static test is conducted in the simulation environment of the Solidworks software as well. The fabrication of the basic chassis frame structure is fabricated using the selected material which is the 25mm x 25mm square mild steel tube with the thickness of 1.6mm and the method of welding is used in developing the chassis. The developed chassis frame structure is able to withstand the applied load with a satisfactory factor of safety (FOS). The chassis structure will further modified and improved into a integrated chassis structure combining with engine, wheels, brakes, motor and steering system.

Obstructive sleep apnea syndrome is a conceivably hazardous ailment. Most end up with non-reversible surgical techniques, such as the maxillomandibular advancement (MMA) procedure. MMA is an amazingly obtrusive treatment, regularly connected to complexities and facial change. Computational fluid dynamic (CFD) is broadly utilized as an instrument to comprehend the stream system inside the human upper airways (UA) completely. There are logical inconsistencies among the investigations into the utilizations of CFD for OSAS study. Thus, to adequately understand the requirement for OSAS CFD investigation, a systematic literature search was performed. This review features the necessary recommendations to accurately model the UA to fill in as an ideal predictive methodology before mandibular advancement surgery.

Abstract. The fuel price hike is currently a sensational national issue in Malaysia. Since the rationalization of fuel subsidies many were affected especially the middle income family. Vehicle aerodynamic were directly related to the fuel consumption, were extra frontal area result a higher drag force hence higher fuel consumption. Roof box were among the largest contributor to the extra drag, thus the roof box shape rationalization were prominent to reduce the extra drag. The idea of adopting water drop shape to the roof box design shows prominent result. The roof box has been simulated using MIRA virtual wind tunnel modelling via commercial computational fluid dynamic (CFD) package. This streamline shape drastically reduce the drag force by 34% resulting to a 1.7% fuel saving compare to the conventional boxy roof box. This is an effort to reduce the carbon foot print for a sustainable green world.