© 2001 by CRC Press LLC which will be used to set up control procedures, is the frame of the unit, i.e., its casing, which connects all models of shape and provides output of reaction forces from the system. The first control procedure which follows from the general structure of mechanical drive units depends on the number of stages of the mechanical drive unit; the second one depends on whether it is an input or output branch of mechanical energy, and the third one depends indirectly on the number of stages. AND nodes in both figures indicate that the following two conditions need to be satisfied to fulfill the required function (in the case of mechanical drive units, the transformation of mechanical energy): • Input of mechanical energy, • Output of mechanical energy. The selection of the basic function structure depends on the gear ratio. The function of component binding is represented by the last node in the basic function structure, and the conceptual design of a technical system, i.e., speed reducer in our case, can be completed with it. Attribute Vector The conceptual design model presented in this section is intended for composing technical systems from existing components. These can be represented entirely by attribute vectors: Attribute vectors can be written on the basis of function trees (Figure 7.11), and these in turn are composed on the basis of existing models of shape. In addition to functions, each description of a model of shape must also contain the following information for the model to function properly: working principles and their auxiliary functions which finally define the working principle, name of the model of shape, including the auxiliary functions which FIGURE 7.11 Function tree. attribute vector fun i , wp ij , auxw ijm , mos ijk , auxm ijn , bfun ijkl ()ϭ fun i function{}, i 12… F,, ,ϭʦ wp ij working principles{}, j 12… W,, ,ϭʦ auxw ijm auxiliary functions of working principles{}, m 12… A,, ,ϭʦ mos ijk models of shape{}, k 12… M,, ,ϭʦ auxm ijn auxiliary functions of models of shape{}, n 12… N,, ,ϭʦ bfun ijkl binding functions{} l 12… B,, ,ϭ,ʦ . structure of mechanical drive units depends on the number of stages of the mechanical drive unit; the second one depends on whether it is an input or output branch of mechanical energy, and the third. transformation of mechanical energy): • Input of mechanical energy, • Output of mechanical energy. The selection of the basic function structure depends on the gear ratio. The function of component binding. procedures, is the frame of the unit, i.e., its casing, which connects all models of shape and provides output of reaction forces from the system. The first control procedure which follows from the general