ABSTRACT This paper describes a wheeled underwater robot developed for locating chemical sources autonomously under stagnant flow conditions. In still water, the released chemical stays in the immediate vicinity of the source location. The search for chemical sources under such conditions is extremely laborious since the presence of a chemical source cannot be detected from a distant place. The chemical sensors on the robot show no response unless a chemical substance released from the source arrives at the sensors. Crayfish in search of food are known to actively generate water currents by waving their small appendages with a fan-like shape. It is considered that the generated water currents help their olfactory search. The smell of food is carried to their olfactory organs from the surroundings by the generated flow, and then is perceived. The robot presented in this paper employs arms mimicking the maxillipeds of a crayfish to generate water currents and to draw chemicals to its sensors. By waving the arms vertically, a three-dimensional flow field is generated and water samples are drawn from a wide angular range. The direction of a chemical source can be determined by comparing the responses of four laterally aligned electrochemical sensors. Experimental results show that the flow field generated by the maxilliped arms is more effective in collecting chemical samples onto the sensors than that generated by a pump. The robot equipped with the maxilliped arms can detect the presence of a chemical source even if the source is placed off the trajectory of the robot.
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M. Ohashi, Y. Kagawa, T. Nakatsuka and H. Ishida, "Crayfish Robot That Generates Flow Field to Enhance Chemical Reception," Journal of Sensor Technology, Vol. 2 No. 4, 2012, pp. 185-195. doi: 10.4236/jst.2012.24026.
 E. A. Arbas, M. A. Willis and R. Kanzaki, “Organization of Goal-Oriented Locomotion: Pheromone-Modulated Flight Behavior of Moths,” In: R. D. Beer, R. E. Ritzmann and T. McKenna, Eds., Biological Neural Networks in Invertebrate Neuroethology and Robotics, Academic Press, San Diego, 1993, pp. 159-198.
 P. A. Moore and J. L. Grills, “Chemical Orientation to Food by the Crayfish Orconectes rusticus: Influence of Hydrodynamics,” Animal Behaviour, Vol. 58, No. 5, 1999, pp. 953-963. doi:10.1006/anbe.1999.1230
 F. W. Grasso and J. A. Basil, “How Lobsters, Crayfishes, and Crabs Locate Sources of Odor: Current Perspectives and Future Directions,” Current Opinion in Neurobiology, Vol. 12, No. 6, 2002, pp. 721-727.
 T. Breithaupt, “Fan Organs of Crayfish Enhance Chemical Information Flow,” Biological Bulletin, Vol. 200, No. 2, 2001, pp. 150-154. doi:10.2307/1543308
 P. G. Brewer, K. C. Hester and N. Nakayama, “Chemical Weapons on the Sea Floor: A Plea for Complete Information,” Proceedings of Oceans 2008—MTS/IEEE Kobe Techno-Ocean, Kobe, 8-11 April 2008, pp. 1-5.
 P. Courmontagne, “A New Approach for Mine Detection in SAS Imagery,” Proceedings of Oceans 2008—MTS/ IEEE Kobe Techno-Ocean, Kobe, 8-11 April 2008, pp. 1-8.
 J. Yoo, S. Tabeta, T. Sato and S. Jeong, “Risk Assessment for the Benzene Leakage from a Sunken Ship,” Proceedings of Oceans 2008—MTS/IEEE Kobe Techno-Ocean, Kobe, 8-11 April 2008, pp. 1-7.
 M. J. Weissburg, D. B. Dusenbery, H. Ishida, J. Janata, T. Keller, P. J. W. Roberts and D. R. Webster, “A Multidisciplinary Study of Spatial and Temporal Scales Containing Information in Turbulent Chemical Plume Tracking,” Environmental Fluid Mechanics, Vol. 2, No. 1-2, 2002, pp. 65-94. doi:10.1023/A:1016223500111
 G. S. Settles, “Sniffers: Fluid-Dynamic Sampling for Olfactory Trace Detection in Nature and Homeland Security,” Journal of Fluids Engineering, Vol. 127, No. 2, 2005, pp. 189-218. doi:10.1115/1.1891146
 P. Denissenko, S. Lukaschuk and T. Breithaupt, “The Flow Generated by an Active Olfactory System of the Red Swamp Crayfish,” Journal of Experimental Biology, Vol. 210, No. 23, 2007, pp. 4083-4091.
 F. W. Grasso and J. Atema, “Integration of Flow and Chemical Sensing for Guidance of Autonomous Marine Robots in Turbulent Flows,” Environmental Fluid Mechanics, Vol. 2, No. 1-2, 2002, pp. 95-114.
 W. Li, J. A. Farrell, S. Pang and R. M. Arrieta, “Moth-Inspired Chemical Plume Tracing on an Autonomous Underwater Vehicle,” IEEE Transactions on Robotics, Vol. 22, No. 2, 2006, pp. 292-307.
 H. Ishida, H. Sakata, T. Moriizumi and T. Breithaupt, “Underwater Odor Compass to Locate a Chemical Source,” Technical Digest of the 10th International Meeting on Chemical Sensors, Tsukuba, 11-14 July 2004, pp. 104-105.
 T. Kikas, H. Ishida and J. Janata, “Chemical Plume Tracking. 3. Ascorbic Acid: A Biologically Relevant Marker,” Analytical Chemistry, Vol. 74, No. 15, 2002, pp. 3605-3610. doi:10.1021/ac0202076