說明 
136 p 
附註 
Source: Dissertation Abstracts International, Volume: 7211, Section: B, page: 6987 

Adviser: Miroslav Krstic 

Thesis (Ph.D.)University of California, San Diego, 2011 

The work in this thesis describes theoretical and experimental results of extremum seeking applied to vehicle(s) with the objective of localizing the source of an unknown, nonlinear, signal field. For environments where position information is unavailable, the extremum seeking method is applied to autonomous vehicles as a means of navigating to find the source of some signal which the vehicles can measure locally. The signal is at maximum intensity at the source and decreases with distance away from the source. Although we only assume that the signal field has a maximum in experiments, to prove theoretical stability we use quadratic form a local approximation of the signal field 

We explore the idea of dealing with a very slow or drifting sensor and provide stability results for several distinct variations of an extremum seeking scheme for 1D optimization and 2D source localization with pointmass vehicle dynamics. Detailed convergence analysis and simulations for steeringbased source seeking with forward velocity regulation applied to nonholonomic vehicles are provided. We develop a deterministic algorithm in a continuum to deploy a group of autonomous vehicles (agents) capable of measuring relative position to neighbors, in a line formation, which has a higher density of agents near the source of a measurable signal and a lower density away from the source in 1D. We also consider stochastic swarming algorithms in 2D that force the net of agents to spread, maintain a formation, and seek a source without position information, whereby each agent is given a local measurement of signal field and the relative distance from neighbors 

Experimental results of extremum seeking applied to mobile vehicles to perform localization, tracking, and levelset tracing of a light source are shown. We perform experiments with multiple vehicles using extremum seeking not only to localize the light source but also to avoid objects and each other. Finally, we discuss details of setting up a testbed to produce a characterized smoke plume and the results of plume source seeking experiments 

School code: 0033 
Host Item 
Dissertation Abstracts International 7211B

主題 
Engineering, Mechanical


Engineering, Robotics


0548


0771

Alt Author 
University of California, San Diego. Engineering Sciences (Mechanical Engineering)

