Papers by Author: Dan Jiang

Abstract: Based on the continuity equation and the motion equation of fluid dynamics, a mathematical model of high pressure transients in water hydraulic pipeline is presented. In the model, the friction item is consist of steady friction item and dynamic friction item, using the Darcy-Weisbach equation to solve steady viscous friction item and using four exponential terms instead of weighting function to solve dynamic friction item. By finite difference method accompanied with Matlab/Simulink, an example of high pressure turbulent flow in water hydraulic pipeline is configured so as to simulate the dynamic characteristics of pressure transients. The comparison between the observed result and the simulation result shows the mathematical model of high pressure transients in water hydraulic pipeline with turbulent flow is reasonable.

Abstract: According to this analysis, we designed a scenario on lower extremity rehabilitation robot communication system based on CAN bus and efficiently solved the problems of low signal processing, computing power and data transfer rate ability for the traditional means of communication of RS232 and RS485.The research deals with the characteristics of communication systems and topological structure, and specifically, with CAN bus protocol design and hardware and software implementation aspects of Communication System designing for some robot sensor.

Abstract: This paper has introduced electromechanical coupling characteristics in portable facility for bearing load, considered model ,according to legs supporting gait when people walking, established the load torque compensation model , and a mathematical model of knee position control system which is made of the servo valve, hydraulic cylinders and other hydraulic components, designed hydraulic cylinder position control loop in case of existing load force interference compensation, and used the method of combining the PID and lead correction network for frequency domain design ,ensured system to meet a certain stability margin. The simulation results show that this position control method can servo on the knee angular displacement of normal human walking, reached a certain portable facility bearing load and assistant power effect, at the same time, met the needs of human-machine coordinated motion.

Abstract: This paper has introduced electromechanical coupling characteristics in the lower extremity exoskeleton systems, considered model ,according to legs supporting gait when people walking, established the load torque compensation model , and a mathematical model of knee position control system which is made of the servo valve, hydraulic cylinders and other hydraulic components, designed hydraulic cylinder position control loop in case of existing load force interference compensation, and used the method of combining the PID and lead correction network for frequency domain design ,ensured system to meet a certain stability margin. The simulation results show that this position control method can servo on the knee angular displacement of normal human walking, reached a certain exoskeleton boost effect, at the same time, met the needs of human-machine coordinated motion.

Abstract: According to this analysis, we designed a scenario on lower extremity rehabilitation robot communication system based on CAN bus and efficiently solved the problems of low signal processing, computing power and data transfer rate ability for the traditional means of communication of RS232 and RS485.The research deals with the characteristics of communication systems and topological structure, and specifically, with CAN bus protocol design and hardware and software implementation aspects of Communication System designing for some robot sensor.

Abstract: According to the durability test results of pen cylinders, including failure modes and fatigue life data, life distribution of pen cylinder is studied. The parameters of Weibull distribution of pen cylinder are estimated by least square method. Using Weibull distribution test, the goodness-of-fit test of the pen cylinder life distribution is carried out. Results of goodness-of-fit test show fatigue life distribution of pen cylinder complies with Weibull distribution with two parameters.

Abstract: Builds finite element model of a small pneumatic cylinder based on ANSYS, deals with the prets179, analyses the stress distribution character of a small pneumatic cylinder .Lastly, the calculation is compared with the test. It is shown that the finite element model of a small pneumatic cylinder with bolt pretension is agreed with the actual situation of cylinder.

Abstract: As a type of solid state switch, MR (magnetoresistive) sensor detects the air cylinder piston’s position in pneumatic control system. The construction and working principle of the air cylinder with MR sensor are introduced. Using 2-D magnetic field finite element analysis (FEA) method, the magnetic field distribution of air cylinder with piston motion is analyzed. Simulation results are given. The magnetic flux density characteristics are compared between piston wear or not.

Abstract: As a necessary component in pneumatic muscle, minimum switch and minimum mechanical hand, pen cylinder used as prime actuator possesses the characteristics of high speed actuation possible, easy installation, improved wear resistance and so on. The construction and working principle of the pen cylinder are introduced. Using 3-D stress field finite element analysis (FEA) method, the stress field distribution of pen cylinder with preload in mounting nut is analyzed. Simulation results are presented. The stress characteristics are compared between different preload in mounting nut and thickness of mounting bracket.