The Design Of A Digital Filter And Its Application In Mechanism Elasto-Dynamics

The digital filtering technique and the mechanism elasto-dynamics are combined in this dissertation to develop a digital filter software. The dynamic response of elastic linkage mechanism is obtained through mechanism elasto-dynamic analysis, then the response data are analyzed by applying the digital filter. This research provides a new tool for analyzing the dynamic characteristics of elastic mechanism . The main work is as follows:A brief description of Digital Filter theory and technique is presented. By comparing kinds of design method of Digital Filter, the Window Function method is chosen to design FIR Digital Filter, an analysis of kinds of Window function method and their frequency responses are given.In order to facilitate the software development, the complicated formula is simplified after analyzing the programming algorithm of the digital filter. The operation relations between Low Pass and High Pass, Band-Pass and Band Stop are given. The varying range and computing method of some important parameters are described. A Digital Filter software in C and VC languages are developed, which has an ease use interface. A complex signal comprising several simple harmonic components is analyzed to check the performance of this Digital Filter software.The State-Space method is applied to compute the differential equation of the elasto-dynamics of mechanism. An example of elasto-dynamic analysis of a plane four bar linkage is carried out, whose dynamic response is filtered by means of the Digital Filter software, the contributions of different frequency components to the whole system response are analyzed.