A Walker Device Modeling, Simulation, And The Drive System Hardware Design

For the actual situation that China has a large number of aged population and lower limb disability people who have trouble in walking, in order to help them to overcome stair barrier, to expand the scope of their activities, this paper puts forward a walking-aid device with stair climbing ability as the research object, the main parts are concluded as follows:First of all, the stair-climbing mechanism of the device is introduced, the automatic and semi-automatic structures are given, and the composition of the switching system is explained According to Ergonomics and stair-climbing constraints, related device dimensions are designed and relevant qualifications are validated. Based on 3D modeling software Solid Works, parts of the device are established and the whole device is assembled.Secondly, the plain kinematic equation of the device is given through simplifying. And according to the mechanism of stair-climbing, joint parameters needed to be controlled are abstracted, the motion character of the climbing process and the corresponding kinematic model are discussed by refining the running process, a kinematics computing graphical user interface is designed. Using matrix transformation theory the kinematic model of a product is computed, our device has a optimized trajectory compared to the product.Then,3D model of the device is imported into ADAMS through intermediate file, device driving function is generated using kinematic data, by adding materials and constraints the virtual prototype model of device is completed. The simulation results demonstrate that the stair-climbing device is feasible and provide reference for actual prototype.Finally, the motor and controller of the stair-climbing structure are selected, and the driving system hardware circuit is designed. The hardware circuit is divided into minimum system, driving module, protection circuit and power circuit. Two driving schemes which based on gate-driving chip and intelligent power module are designed respectively, the debug results show that hardware circuit is well-designed.