Micro hopping robot with IR sensor for disaster survivor detection

Abstract

Collapsed buildings due to earthquake or terrorist attack typically result in a rubble pile with access holes less than 1 foot in diameter. The necessity of producing smaller robots which can locate survivors quickly is evident in light of recent disasters and attacks. In the reported research, instead of developing one or two expensive robots, the proposed concept is to manufacture thousands of less expensive micro robots (< $10/micro robot) which can access small openings in the rubble pile. Therefore, the probability of locating survivors increases exponentially due to the exponential increase in the number of robots and because these smaller micro robots can move through small openings which larger robots are not be able to access. Key to the approach is to place the micro robots at the top of the rubble heap so that little energy is consumed as the micro robots search downward (carried by gravity) when not utilizing their own power source. In this report, small hopping robots which have a simple locomotion mechanism and IR sensory elements have been developed to detect survivors under collapsed buildings. This small robot includes micro eccentric motors for generating lift and thrust forces, and IR sensors for detecting the thermal signal of survivors. Therefore, the micro robot can crawl without any wheels or legs even on small, rough terrain with the help of eccentric mechanical vibration. This tiny robot also has the ability of self-righting to allow it to keep moving to the target even if it falls and lands in any position. Weight balance as well as resonance parameters are very important to achieve good mobility. Automatic navigation to the target is achieved with simple on-off motor switching. The simple design layout results in not only lightweight robots but also low cost allowing employment of a large number of robots in the dangerous rubble field. Initially, a small robot utilizing off-the-shelf components (i.e. micro motors, button batteries, sensors and electronics) was designed and assembled to verify feasibility for rescue operations. In the initial experiments, many small robots with optical and IR sensors have been developed and movement toward a human body under zero light conditions has been successfully demonstrated.