Vibration Damping Research In The Crus Of Biped Robots

The biped robots with humanoid features have drawn more and more attention in the field of robotics, along with the development of science and technology and the improvement of people’s living standard. Thus, widespread applications and bright business prospects can be expected. However, the stability and speed of walking will be influenced by the impact effect from the bottom up due to the touch between the foot and ground. Meanwhile, the performances of the sensors mounted on the upper part of the biped robots platform are also affected. From this perspective, it makes sense to adopt certain isolation or rejection measures for the disturbance coming from the ground, which provides a new approach to the optimization of stability of walking.Based on the design concept of the first generation of the biped robotic crus with damping function, the second generation including the advantages of the first one has been designed and manufactured. It consists of the design and realization of the ac-tive actuator and the damping crus bracket. Digital signal processor TMS320F28335 is chosen as a master controller, while the controller chip inside the driver is serving as a slave controller. This kind of design leads to more available options of control meth-ods for active vibration attenuation systems. The analog-to-digital converter AD7656, which expands the range of input signal, serves as the signal acquisition unit of the ac-celeration sensor. The electromagnetic interference problem has also been resolved by adopting insulation measures and the experiment of damping crus is implemented for experimental study.The dynamics of the damping crus have been carefully analyzed and the corre-sponding mechanism model has been built. The filtered-x least mean square (Fx-LMS) algorithms are chosen for active vibration attenuation during simulation experiments, with fixed-step factor and variable-step factor based on fuzzy inferences, respective-ly. The simulation results show that the joint active and passive vibration attenuation method performs better than the traditional passive one. However, the mechanism mod-el cannot reflect exactly the interconnection of different vibration transmission channels and the mutual interference of different forces. Thus, a virtual mechanism model of damping crus based on SimMechanics is built. The active disturbance rejection control algorithm is implemented for simulation study. At last the ADAMS model of damping crus is constructed for simulation study.