仿生张拉机械腿及其抗冲击性能仿真分析

Design of bionic tensegrity leg and simulation analysis of its impact resistance

针对机器人腿足系统抗冲击性能差的问题,基于生物张拉原理开发了一种仿生张拉机械腿。该机械腿关节间不存在刚性铰接轴,通过添加柔性材料模拟生物关节韧带和筋腱作用。仿真结果表明:相比传统机械腿,仿生张拉机械腿具有更好的抗冲击性能。材料敏感性分析表明,足-地冲击过程中,仿生张拉腿中的柔性构件通过变形有效吸收冲击能量,缓释了冲击作用强度,改善了刚性构件的应力分布状态。研究范围内仿生筋腱材料软硬保持不变,仿生韧带的弹性模量越小,仿生腿的抗冲击、抗弯能力越强;保持仿生韧带软硬一定时,仿生筋腱的弹性模量越大,仿生腿的抗冲击、抗弯能力越佳,进而为机器人腿足系统的创新设计提供了理论依据。

To solve the problem of poor impact resistance of robot leg and foot system,a bionic tensegrity mechanical leg was developed based on the principle of biological tensegrity. Flexible materials were employed to simulate the biological joint ligament and tendon,instead of using rigid hinge joint. Finite element simulation results show that the bionic tensegrity mechanical leg has better impact resistance than the traditional mechanical leg. The material sensitivity analysis results show that during impact,the flexible member in the bionic tensegrity leg absorbs the impact energy effectively through deformation,reduces the impact strength,and improves the stress distribution state of the rigid member. Within the scope of the study,keeping the elastic modulus of bionic tendon material as constant,the smaller the elastic modulus of the bionic ligament,the stronger the anti-impact and anti-bending resistance of the bionic leg. Similarly,when the bionic ligament is kept constant,the larger the elastic modulus of the bionic tendon,the better the anti-impact and anti-bending resistance of the bionic leg. Furthermore,this project provides important theoretical basis for the innovative design of robot leg-foot system.