The Fundamental Aspects of the Structural Theory of Multispeed Transmissions Control

The first level task among the tasks of analysis and synthesis of the control systems (CS) for multispeed transmissions (MT) is the organization of speed shifts process. The method of synthesis of electrohydraulic schemes of mechatronic CS, that is based on the theory of discrete logical devices is worked out by us (see SAE Tech. Pap. Ser. 2003-01-0319). It was shown, that there is a close relation between the structures of CS and MT. Therefore it is necessary to know the properties of MT as the object of control.

The analysis of such properties is the subject of this paper. It is shown that the relation between CS and MT at the level of their structures may be described quite fully with help of three basic parameters of MT kinematics schemes: the number of freedom degrees, the number of control elements (CE), the number of speeds. The concept of generalized CS and MT is introduced. This concept permits to give quantitative evaluation of their multiplicity, to formulate and to decide the series of structural tasks by using mathematical methods of combinatorial analysis and graph's theory.