Analysis Of Locust’s Grasping And Jumping Kinematical Reaction Force Experiment

Locust’s kinematics force measuring system is used to measure the reaction force betweenlocust’s feet and the surface when it is crawling and jumping on all kinds of surface（on horizontalsurface, on walls, on ceilings），and write down images of locust’s movement at the same time. Thesystem is consisted by3-dimensional sensor array，signal conditioning system，images requiringsystem and measuring software.A large number of force data and image were obtained by the test system after a great amount ofexperiment. The grasping behavior of locust’s body and tarsi was researched，meanwhile，the graspingmechanism of locust was analyzed on different substrates. The interaction between pads andsubstrates may improve the stability of contact, and claw tips may play a key role in keeping theattachment reliable. Besides, lateral force may be extremely important in keeping the contact fromsliding.To research the grasping forces of locust’s claw, the force and moment equilibrium equations ofclaws were established. Besides, the equations between grasping force, lateral force and normal forcewere established. The results of calculation showed that the contact angles, support angles and frictioncoefficient affected the grasping forces.Data on jump morphology of locusts were obtained from high-speed video recordings, whereasthose on the reaction force of hind legs were collected using sensors. The results showed that thetrajectory control was achieved by rapid rolling and yawing movements of the locust’s body, causedby the fore and middles in cocking and co-contraction phases, and caused by the hind legs intriggering phase. The final jump trajectory was not determined until hind tarsi left platform. Thehorizontal co-impulse between two hind legs might play a key role in jump stability and accuracy.Besides, the angle between two hind legs affected the control of jump trajectory but had little effect onthe elevation angle of a jump, which is controlled mechanically by the initial positions of the hindlegs.The results have obvious implications for inspired the design of bio-inspired robot.