Study On The Model And Algorithm Of Non-Tree-Shape Mechanical System Motion Simulation

The model, algorithm and technical application of motion simulation for non-tree-shapemechanical system are studied on the basis of Mechanical System Virtual Prototyping SimulationSoftware System developed by one of former colleagues. Some essential problems, such as thealgorithms of Differential-Algebraic Equations (DAE), the method of making non-tree-shapesystems be tree-shape systems, the operations on the redundant constraints and the users-inputfunctions are solved in order to broaden the general model and algorithm of mechanical system.The basis research and develop work are carried out to promote an integrate mechanical systemmotion simulation system. The applications about this technique are also practiced and probedsuccessfully.The dynamics theory of non-tree-shape mechanical system is investigated founded on thepreceding dynamics algorithm of tree-shape mechanical system. The calculation of all the users-input functions is realized to improve the practicable level of the mechanical system motionsimulation system and apply the system in some relative fields. Concerning these works, the paperis researched comprehensively and thoroughly.First, the key theories and methods on the mechanical system motion simulation arediscussed, including the mechanical system model, the o~ject-oriented method, the data structureof graph, the multi-body system dynamics theory, the algorithms of DAB, and so on. Thesetheories set up the base of the following research work.Next, the structure and characteristic of non-tree-shape mechanical system are indicatedthrough the method of graph theory, and the method to make non-tree-shape systems be treesystems are advanced. The selecting rules of redundant constraints and the automatic derivedmethod of the spanning tree are given. Accordingly, the non-tree-shape multi-body system can beanalyzed and solved by the dynamic algorithm of the tree-shape system. After the additionalconstraint equations, the constraint-matrix and its complement-matrix are solved, through multi-body system dynamics theory and numerical analysis theory, the basic dynamics equations aresubtracted and the DAB can be changed into pure differential equations by the constraint-matrix-cut method. Therefore the dynamics algorithm of the ngn-tree-shape mechanical system based onthe Kane-Huston d~pamics theory is obtained. Then the users-input functions for the mechanicalsystem motion simulation are deliberated. The whole process of searching, identifying, saving,analyzing, getting and accessing the functions from the users data file is completed automatically.A general model including the functions is developed, which can be well used in the course of themotion simulation.As an implementation and verification, the algorithm mentioned above is changed intocomputer programs by means of the object-oriented modeling method and the language C++.Consequently, the Solving Module of Mechanical System Motion Simulation Software(MSMSS) is made more practical than before. Several typical cases are analyzed by ADAMSand the MSMSS program developed by the author, respectively. The results calculated by the?II ?MSMSS program are very similar with those by ADAMS.Finally, the 3-D human multi-body system models are established. By imposing some extrarestraint, motions and other environments, the human body models can be used in the researchfield of human-machine system motion simulation. The method will come to be an application ofthe technique on mechanical system motion simulation.