A series-parallel hybrid bionic manipulator with flexible driving joints
Current collaborative robots typically adopt a serial rigid structure,which limits their compat-ibility with human environments and constrains their range of applications.To address the shortcom-ings of collaborative robots in terms of flexibility and environmental adaptability,a 6-degree-of-freedom hybrid serial-parallel robotic arm,SoftArm-6,is designed based on the flexible parallel driv-ing mechanism of human arm muscles.The robotic arm consists of three serial degrees of freedom in the arm section and three parallel degrees of freedom in the wrist section,with flexible joints driven by Series Elastic Actuators(SEA).By establishing a kinematic model for the robotic arm and applying the principle of mechanism equivalence,the posture decoupling of the hybrid serial-parallel robotic arm is realized.Furthermore,an online trajectory teaching method based on Kinect human motion capture is proposed.To address issues such as reduced positioning accuracy and susceptibility to oscillations caused by the SEA flexible joints,a feedforward gravity compensation algorithm based on the virtual displacement principle is designed.Finally,the trajectory tracking and teaching-based grasping experi-ments are conducted on the SoftArm-6 prototype.The results show that the deviation in trajectory tracking tasks is less than 1.5%,and the grasping success rate reaches 98%,significantly improving both operational precision and environmental adaptability.This design provides new technical support for the application of collaborative robots in complex and uncertain environments.
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维普
