Dynamic Model And Control Method Of Electrorheological Transmission System

Electrorheological (ER) fluids are a new-type of intelligent soft matter widely concerned in the 21st century, and ER technology is one of the key technologies and frontiers in electromechanical engineering. Dynamic model and control method of ER device are significant in the field of ER technology.ER transmission system (ERTS) is a nonlinear and time-variant system with multiple inputs and multiple outputs, which brings about great difficulties in its modeling. Testing and controlling of ER device is the key difficult problem of ER technology. In present dissertation, not only the dynamic model but also the control method of a double driven ERTS is investigated in detail.The performance of ER actuator relates to the structure parameters, the qualities of ERF as well as the operating conditions. BP neural network (NN) based on Levenberg-Marquardt (LM) algorithm is used to identify the ERTS. Despite the pretty good accuracy, the physical signification of NN model is obscure. In order to figure out this problem, a discrete dynamic model of ERTS set up by means of dynamic analysis is presented at length, which can offer us desirable information for improving the design, manufacturing, analysis, simulation, prediction and controlling. Due to setting up of discrete dynamic model, the complex nonlinear relation between ER effect and the strength of applied electric field can be also solved effectively. Furthermore time series analysis (TSA), a new effective and credible method, is introduced to apply in ER technology field for the first time.In addition, the network testing and controlling system of the ERTS is set up based on virtual instruments. The network experimental platform is versatile, on which many experiments of electromechanical engineering can be carried out easily and expediently.Using the ER fluids with nano spherical particles prepared by the author, a great amount of experiments is carried out under the circumstances of variable input signals, variable loads and random interference. The author finds that, firstly, the output angles accord approximately with the input angles owing to the proper control strategy and model. Secondly, a lower rotational speed of stepper motor can produce a bigger enlargement factor of torque comparing with a high rotational speed. Moreover, the effect of shear rate on ER effect is not distinct within a range of shear rate.Finally, it is necessary for the author to acknowledge numerous academic resources, such as ER technology, smart soft matter technology, mechanical design, fluid mechanics, testing and controlling technology, network technology, virtual instruments technology, time series analysis, and so on. It's certain that the results of present research provide instructive theory and experimental data for engineering application of ER technology, and also present academic and experimental fundament to develop electromechanical products of new generation with complete intellectual property in our country.