Hongmiao Zhang

Dynamic analysis and optimization for the ankle joint prosthesis

Nowadays, a comfortable ankle prosthesis with natural walking gait for the amputee has become an important requisite. In this paper, a new kind of active ankle prosthesis is presented, which can not only help amputees walk naturally, but also reduce energy consumption by recycling. Firstly, the structure of ankle prosthesis was proposed. And then, dynamic simulation and structure parameters optimization for the prosthesis were carried out in Adams software environment. Finally, energy consumption in a gait cycle was calculated based on the dynamic simulation. We conclude that our ankle joint prosthesis can greatly reduce the energy consumption.

Structure design and analysis of compliant human-machine interface mechanism for exoskeletons

Due to the difference between kinematics of human joints and exoskeleton joints, joint misalignment may be brought about by human-machine interface (HMI). Joint misalignment may lead to undesired interaction forces, if not copped with properly, e.g. in the HMI mechanism with straps. In this paper, firstly the interaction forces caused by joint misalignment in HMI mechanism with straps are studied. Then, a compliant HMI mechanism which consists of passive mechanical linkages is presented and Degrees of Freedom (DOFs) of the whole human-machine system are analyzed. A simulation model of human-machine system is established for analyzing the interaction forces in the compliant HMI mechanism. Finally, comparative results were obtained to demonstrate that the constraint forces can be decreased greatly with sufficient driving forces simultaneously by using of the compliant HMI mechanism.

Research on force sensing system for a colonoscopy robot

A force-sensing system for a colonoscopy robot is proposed. It undertakes a modular design, composed of strain gauges. This paper first makes a modeling and simulation analysis of surface deformation for the colonoscopy robot. And then, based on the results of the analysis, the structural design of the sensor is improved. Finally, after designing a pressure sensing and signaling circuit, an experiment done on identifying the sensor parameter is described. The acceptable performances of the force sensing system are verified through experiments.