131 |
The low-level guidance of an experimental autonomous vehiclePears, Nicholas Edwin January 1989 (has links)
This thesis describes the data processing and the control that constitutes a method of guidance for an autonomous guided vehicle (AGV) operating in a predefined and structured environment such as a warehouse or factory. A simple battery driven vehicle has been constructed which houses an MC68000 based microcomputer and a number of electronic interface cards. In order to provide a user interface, and in order to integrate the various aspects of the proposed guidance method, a modular software package has been developed. This, along with the research vehicle, has been used to support an experimental approach to the research. The vehicle's guidance method requires a series of concatenated curved and straight imaginary Unes to be passed to the vehicle as a representation of a planned path within its environment. Global position specifications for each line and the associated AGV direction and demand speed for each fine constitute commands which are queued and executed in sequence. In order to execute commands, the AGV is equipped with low level sensors (ultrasonic transducers and optical shaft encoders) which allow it to estimate and correct its global position continually. In addition to a queue of commands, the AGV also has a pre-programmed knowledge of the position of a number of correction boards within its environment. These are simply wooden boards approximately 25cm high and between 2 and 5 metres long with small protrusions ("notches") 4cm deep and 10cm long at regular (Im) intervals along its length. When the AGV passes such a correction board, it can measure its perpendicular distance and orientation relative to that board using two sets of its ultrasonic sensors, one set at the rear of the vehicle near to the drive wheels and one set at the front of the vehicle. Data collected as the vehicle moves parallel to a correction board is digitally filtered and subsequently a least squares line fitting procedure is adopted. As well as improving the reliability and accuracy of orientation and distance measurements relative to the board, this provides the basis for an algorithm with which to detect and measure the position of the protrusions on the correction board. Since measurements in three planar, local coordinates can be made (these are: x, the distance travelled parallel to a correction board; and y,the perpendicular distance relative to a correction board; and Ɵ, the clockwise planar orientation relative to the correction board), global position estimation can be corrected. When position corrections are made, it can be seen that they appear as step disturbances to the control system. This control system has been designed to allow the vehicle to move back onto its imaginary line after a position correction in a critically damped fashion and, in the steady state, to track both linear and curved command segments with minimum error.
|
132 |
Structure borne sound in motor-vehicles using statistical energy analysisFraser, Grant January 1998 (has links)
This Thesis is about the application of Statistical Energy Analysis (SEA) to the study of noise and vibration in motor vehicles. Methods for predicting the transmission of structural waves between body panels in motor cars are given. A complex joint technique based on the wave dynamic stiffness approach is discussed in detail. This technique can account for the complexities of the joint structures found in motor vehicles. Transmission of vibration energy between panels connected by a curved section of panel has been investigated using the complex joint modelling technique. Wave Intensity Analysis(WIA) and SEA were used to calculate the coupled panel vibration levels based on transmission coefficients calculated using the complex joint techniques. Energy Level Differences (ELDs) were measured for comparison with predicted results using laboratory models. SEA failed to accurately predict the ELDs except at low frequencies. However WIA was able to predicted the ELDs with reasonable accuracy using an existing expression for transmission at a panel corner joint. Two SEA models of a small passenger car have also been constructed. One assumes simpler joint configurations when calculating transmission coefficients and the other uses the complex joint technique. Panel ELDs were measured using a small passenger car. The SEA model using the complex joint method gives better agreement with measured ELDs than did the model using the simpler joints. saloon Sound Pressure Level (SPL) as a result of engine noise was measured. Both SEA models of the vehicle gave good agreement between measured and predicted Saloon SPL. A noise problem associated with exhaust misalignment is also investigated.
|
133 |
Investigation of 50 km/h speed zone :Nalluri, Gopi Krishna Unknown Date (has links)
To date, the 50 km/h General Urban Speed Limit (GUSL) has been implemented to some local residential streets in the City of Port Adelaide Enfield (hereafter referred to as Port Adelaide), South Australia as a Local Area Traffic Management (LATM) scheme since March 2003 aiming to reduce travel speeds and traffic volumes so as to enhance road safety and amenity of residential areas. Port Adelaide is located approximately nine kilometres away from the North-west of Adelaide Central Business District (CBD). There are major express highways and freight roads enclosing Port Adelaide, and within the boundaries is composed of many arterial and collector roads. All of these arterial roads and some major collector roads line in north-south direction. As a result of these geographical characteristics, Port Adelaide is a city covering the major direct routes for residents and major freight route for goods transport in the north-west suburbs. / However, one of the problems occurring in Port Adelaide seems to be characteristics of grid road networks lacking clear road hierarchy, which can be seen from many local streets connecting directly with nearby arterial and/or collector roads. Furthermore, as described previously Port Adelaide consists of many freight routes, arterial routes, and these characteristics cause another problem. Traffic is induced to divert to local streets, which are relatively straight, and uses them as an alternative route causing many problems to residents in the local area due to travel demands during rush hour. To this point, it can be seen that the 50 km/h GUSL scheme might not be as efficient as it should be in deterring through traffic since the implementation of traffic management has not covered a macro scale, which in this case is arterial roads forming a connective grid. / This study seeks to present the analysis of traffic data in terms of traffic volumes, mean speed and 85th percentile on three different local residential streets during weekday and soma crash data analysis is also done on two study streets. The expected results of this study may be taken as samples for further research in future. / Thesis (MTransportSysEngineering)--University of South Australia, 2006.
|
134 |
A preliminary system baseline for a U.S. Army Light Armored Assault Vehicle /Brown, Robert Mark, January 1989 (has links)
Project report (M.S.)--Virginia Polytechnic Institute and State University, 1989. / Vita. Abstract. Includes bibliographical references (leaves 68-71). Also available via the Internet.
|
135 |
Development of a tandem-wing flapping micro aerial vehicle prototype and experimental mechanismDiLeo, Christopher. January 2007 (has links)
Thesis (M.S.M.E.)--University of Delaware, 2007. / Principal faculty advisor: Xinyan Deng, Dept. of Mechanical Engineering. Includes bibliographical references.
|
136 |
Motor vehicle wealth taxes and fleet age air quality implications /Barbour, Karie Anne, January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Tennessee, Knoxville, 2004. / Vita. Includes bibliographical references (p. 93-98). Also available online via the University of Tennessee Electronic Theses and Dissertations website (http://web.utk.edu/~thesis/etd.shtml).
|
137 |
Pseudo-Linear Attitude Control and Estimation System (PLACES).Leung, Winnie Suk Wai. January 2004 (has links)
Thesis (M.A. Sc.)--University of Toronto, 2004. / Adviser: C.J. Damaren.
|
138 |
Recovery of precious metals from automotive catalytic converters /Wu, Kuo-ying Amanda. January 1993 (has links)
Thesis (Ph.D.)--University of Tulsa, 1993. / Includes bibliographical references (leaves 172-181).
|
139 |
Design of a battery charger for the NASA EOS space platform /Sizemore, Tom, January 1991 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Bibliography: leaves 124-125. Also available via the Internet.
|
140 |
Simulation approach to the study of driving behaviour, fuel consumption, and emissions /Fukutomi, Akihira, January 1900 (has links)
Thesis (M. App. Sc.)--Carleton University, 2004. / Includes bibliographical references (p. 144-151). Also available in electronic format on the Internet.
|
Page generated in 0.0262 seconds