Animal's Surface Reaction Forces: Measuring System, Experiments And Analysis

Locomotion is the basis of predation, escape, reproduction for animals. Geckos, spiders and insects run and climb with exceptional speed, strength and agility for their size, representing in many respects an ideal model system for the study of terrestrial locomotion. Biologists make comparative biology study with animals to develop a deeper understanding of the foundmental biomechanical design rules common to all legged organisms. Engineers look to animals'locomotion for design principles to improve the performance of legged robots including wall-climbing robots and other complex systems. By measuring the ground reaction forces generated by animals when walking upright, climbing vertically or walking on an inverted surface, we can understand adhesion mechanism and locomotion dynamics. Two kinds of 3 dimensional force sensors in different range were made to measure the ground reaction forces generated by animals such as geckos, spiders, insects etc. first, the elastic elements of sensors were designed optimally and strain gages were glued to elastic elements in right position. Secondly, the circuits of signal amplification and condition were also made to acquire the data. Then the software of data acquisition and analysis was compiled. These two kinds of 3 dimensional force sensors were made calibration before used to measure the ground reaction forces.An insects's kinematic mechanics measurement system was created to measure the ground reaction forces produced by animals in different legs at the same time. With this system and the high speed camera , the cooperative adhesive mechanics among all legs of insects when locomotion can be acquired. The sensor array of the system were composed of 16 3-dimensional sensors in smaller range on 4×4 pattern. A mechanical device was installed in sensor array to achieve over-load protection. National Instruments Company's SCXI signal conditioning modules were used in this system to compose 48 channels signal amplification, data acquisition and processing device. The software of data acquisition and analysis was compiled in LabVIEW environment. Another sensor array which will be use to measure the gecko's cooperative adhesive forces was designed also with several sensors in bigger range A 3 dimensional force sensor in bigger range was use to measure the ground reaction forces generated by geckos when walking upright and climbing vertically. By measuring the different target surface reaction force,we can understand gecko's adhesion mechanism and locomotion. The study sheds light on the study of animal's locomotion and the design of bio-inspired robot. Legs of stinkbug Erthesina fullo performance during walking was examined with a model. A 3 dimensional force sensor in smaller range was used to measure the ground reaction forces created by individual legs of the stinkbug when moving on the level and vertical surfaces. The legs of insect generate adhesive forces to avoid overturning when climbing vertically.Morphology of Lycorma delicatula was studied with microscope. The insect possesses arolium between claws to adhesive on smooth surface when walking. Adhesive forces and contact area between arolium and the target surface were measured when Lycorma delicatula walked on the level and slided on the vertical surface. A model of peeling theory was put forward to give relationship between contact area and adhesive forces.The force of free swimming water striders was measured about 0.3 - 0.4 mN/cm. The error calculated by comparing force and geometrical derived data, was estimated as 13%. Females in average were stronger than males, however the ratio force / weight was not significantly different. Compared to other lighter species' data available in literature, water strider A. paludum seems to be stronger, but the ratio force / weight is actually lower.