| Engineers envision a world where odor-tracking, mobile robots can locate the source of toxic gas or detect unexploded ordnance, but such tasks cannot be efficiently executed until olfaction is fully understood. Given the poor sense of smell in humans, it is no wonder that what is known about olfaction is gathered from scientists' observations of the odor-mediated behaviors of organisms. However, these observations are often made in a controlled laboratory environment where animal behaviors are easier to analyze than in their natural habitats. Engineers then use these behaviors as inspiration for odor source localization algorithms, but rarely is this done in cooperation with scientists using actual data from behavioral experiments to test their effectiveness. Perhaps more cooperation between the two communities is needed to solve the odor source localization problem.;This thesis is a collaborative effort between the Department of Fisheries and Wildlife and the Department of Mechanical Engineering at Michigan State University to identify how ovulating female sea lampreys track the male sex pheromone (3kPZS) to its source. Three control algorithms are presented herein that each test a different orientation hypothesis. The algorithms are then evaluated in computer simulations of the natural environment. The resulting trajectories are compared with actual observed trajectories using statistics. Based on this comparison, the best-performing algorithm is chosen. Strong evidence suggests that sea lampreys use odor-conditioned rheotaxis to locate the source of synthesized pheromone, as opposed to chemotaxis or strictly rheotaxis. |
