Research On The Technology Of Pneumatic Worm-like Soft Robot With Circular Longitudinal Muscle Compound

As a next generation robot,the soft robot which is made of flexible materials has high flexibility and multi-degree of freedom.It has strong adaptive ability in complex environment and narrow space.Thus,it can be applied to the field of resource exploration,medical testing,relief,etc.Current research about soft robots have some disadvantages,such as the single form of motion,the existence of backward sliding,slow speed,difficulties of control,etc.Therefore,to solve these problems,it is of academic importance that a new type of pneumatic earthworm-like soft robot with circular-longitudinal compound muscles researched and developed.This pneumatic earthworm-like soft robot driven by compressed air has many advantages,such as the compact structure,multiple form of movement and strong adaptive ability.It can not only realize the rectilinear crawling,but also cross barriers.In this thesis,based on the study on the moving mode and physical structure of earthworm,the general structure of two cavities combined earthworm-like soft robot with circular-longitudinal compound muscles has been designed.Also,the moving form of pneumatic worming soft robot has been analyzed.Based on the simplified model of pneumatic earthworm-like soft robot,the structural parameters of circular and longitudinal muscle have been analyzed by simulation.The basic size of circular and longitudinal muscle and the density of mental position-limited rings have been determined.The prototype robot has been made out through casting moulds.In order to obtain the axial expansion and the bending deformation of somite in pneumatic earthworm-like soft robot,much verification and characteristic testing has been made.The result shows that the deformation of somite increases with the driven pressure and it is consistent with the simulation result.On top of that,the connection between the size of slider and driven pressure of artificial circular muscle has been analyzed by experiments.The driven pressure is determined as 40kPa based on the practical requirement.The testing about the response time of somite expansion has also been made.The result shows that the response time of air inflation in vertical artificial muscles longer than the air bleeding and the response time in different crawling surfaces has differences at the same driven pressure.Based on the moving requirement of pneumatic worming soft robot,the pneumatic and electrical control circuit has been designed.The rectilinear,turning,climbing and crossing barrier testing has been made.The results show that in the crawling process of pneumatic worming soft robot,the backward sliding has not existed.The velocity of rectilinear crawling is 18mm/s,when the driven pressure is 150kPa.Also,the robot can turn a cycle of 37.8°,when the left cavity in longitudinal muscle is 120kPa and the right is 40kPa.The maximum climbing angle of the pneumatic worming soft robot is 17.8° and the maximum height of crossing barrier is 6mm.