摩擦接触约束下的微小管道机器人管内运动稳定性分析

Motion Stability Analysis of Micro In-pipe Robot with Frictional Contacts

针对管径为15～20mm的细小管道,提出一种新型蠕动式微小管道机器人设计方案,虚拟样机仿真发现机器人管内运动存在不稳定情况。为进一步指导设计、优化系统结构,建立该机器人受摩擦接触约束条件下管内运动的动力学模型,利用线性互补理论对其进行降阶处理,讨论其解的存在性和唯一性问题,利用Kelvin接触模型和奇异摄动理论揭示受限机器人降阶模型接触力稳定性的附加条件,利用该模型对机器人在直管运动的稳定性情况进行仿真,根据仿真结果对机器人结构提出改进方案。通过虚拟样机仿真和试验验证理论分析的正确性及结构改进的合理性。

A novel design of creeping micro in-pipe robot is presented, aiming at micro pipelines with diameters of 15~20 mm. The instability of robot motion is found through virtual prototype simulation. To further provide guidance for the design and optimization of the system structure, the dynamic model of robot motion under constraint condition of frictional contact is established. The reduced-order model is obtained with linear complementarity theory. Existence and uniqueness of solutions to the model are discussed. Kelvin model and singular perturbation are used to reveal the additional conditions for ensuring contact force stability in the reduced-order model. The stability of the robot moving in straight pipe is simulated. And improved design of the robot structure is proposed according to the simulation result. Correctness of the theoretical analysis and advantages of the improved design are proved by virtual simulation and experiments.