Research On The Holding Stability Of Climbing Robot Based On Under-actuated Mechanism

The climbing robot,as an important branch of the special robot,has become a research direction by many domestic and foreign research institutions.The various types of developed climbing robots have applied in industry,agriculture,military and aerospace fields,and could carry out on-site construction,maintenance,reconnaissance and monitoring.Most of the existing climbing robots are developed for specific scenarios,and have multi-drive components,control cumbersomely and poor adaptability.This topic introduced the idea of under-actuated into the design of climbing robot,and developed a novel wheel-manipulator climbing robot based on under-actuated mechanism,which has some characteristics of adaptive well,drive less components and simple control.The holding stability of climbing robot is analyzed,which could provide theoretical support for the design improvement of climbing robot with high stability.Firstly,based on the function and working principle of climbing robot,we have designed the structure of climbing hold module and driving module of climbing robot,and completed the overall design of climbing robot.The modeling and kinematics analysis of the under-actuated limb of climbing robot are carried out to verify the correctness of the holding principle.The static analysis of the under-actuated link mechanism is established,and the contact force expression of each phalanx is derived,which proposed the holding stability physical description preliminarily.Then,the holding stability of climbing robot's under-actuated limb is analyzed,including the holding stability problem of two-DOF under-actuated phalanx and three-DOF under-actuated phalanx,and the stability physical description of enveloping holding object of climbing robot is put forward in detail.We made the simulation analysis of climbing robot,and collected the corresponding data to verify the working principle of climbing robot and the correctness and reliability of the theoretical analysis from the kinematics and dynamics.Finally,the physical prototype of climbing robot is assembled,and the key components are arranged,which contributed to build the experimental platform.Based on the climbing robot experimental platform,we carried out the holding and climbing experiment,collected and analyzed the data of each phalanx joint rotation angle and contact force.Through the analysis of data curve and observing the phenomenon,the flexibility,adaptive performance and holding stability of climbing robot are verified,and the correctness of the results of dynamic simulation analysis is proved,thus further verifying the rationality of the climbing robot's stability analysis.