Unmanned Autonomous/Ground Vehicle

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Acknowledgement

I would take this opportunity to thank my research supervisor, family and friends for their support and guidance without which this research would not have been possible.

DECLARATION

I, [type your full first names and surname here], declare that the contents of this dissertation/thesis represent my own unaided work, and that the dissertation/thesis has not previously been submitted for academic examination towards any qualification. Furthermore, it represents my own opinions and not necessarily those of the University.

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Chapter 1: Introduction

Unmanned ground vehicles (UGVs) have many potential applications, both in military and civilian areas, such as reconnaissance, surveillance, target acquisition, search and rescue, and exploration. Knowledge of UGV behaviors under control commands on different terrain types plays an important role on improving their safety, reliability and autonomy. In this thesis, the complex processes involved in a UGV driveline and its interaction with terrain will be thoroughly analyzed and a robust low-level control scheme will be developed for driving the autonomous vehicle. An overview of the research will be provided in this proposal.

The thesis will focus on issues of vehicle modeling incorporating wheel-terrain interaction and low-level control design taking into account uncertainties and input time delay. Addressing these issues will be of significant importance in achieving persistent autonomy for outdoor UGVs, especially when navigating on unprepared terrains. The test-bed vehicle used for this research will be retrofitted from an all-terrain 20-hp, 0.5- tonne vehicle. Its driveline system will consists of an internal combustion engine, continuous variable transmission (CVT), gearbox, differential, chains, and eight wheels (Setlur, 2006, 108).

The vehicle will be driven in the skid-steering mode, which is popular for many off-road land- vehicle platforms. In this thesis, a comprehensive approach will be proposed for modeling the driveline. The approach considers the difference in speed between two outputs of the differential and the turning mechanism of the vehicle. It will describe dynamics of all components in the vehicle driveline in an integrated manner with the vehicle motion. Given a pattern of the throttle position, left and right braking efforts as the inputs, the dynamic behavior of the wheels and other components of the UGV can be predicted.

Chapter 2: Literature Review

Unmanned Ground Vehicles

A UGV is defined as "any piece of mechanized equipment that moves across the surface of the ground and serves as a means of carrying or transporting something, but explicitly does not carry a human being". In the robotic community, a UGV is usually considered as an automated motion platform or just a mobile robot.

It can be classified as tele-operated or autonomous depending on whether it requires human intervention or not. A UGV is sometimes called an autonomous land vehicle (ALV). Over the years, many efforts have been made in UGV development. Shakey, built at Stanford Research Institute from 1966 to 1972, can be considered as the first major development in the UGV field. Equipped with a TV camera, an ultrasonic range finder, and bump sensors on a three-wheeled platform, it had a restricted capability in ...