Abstract: In order to solve a huge amount of complex optimization calculation of 4-DOF planetary gear mechanism schemes, the scheme characteristics of four-degrees-of-freedom planetary gear transmission mechanism are studied. According to the kinematic relationship among the components of four degrees-of-freedom planetary gear transmission, a mathematical model is established for the coefficients of braking component, clutch and auxiliary component, the gear ratios, the characteristic parameter of planetary gear row, the relative speed of planetary gear, the control torque and efficiency in scheme model. For all possible scheme models with same mechanism, the internal rules of the performance indexes are analyzed to provide a theoretical basis for model classification. A method of component group model classification based on the same control logic principle is put forward. The same kind of component group models can be calculated for one time by using the proposed method for choice of feasibe transmission schemes. The calculated results shows that the proposed method can be used to reduce the optimization calculation of planetary transmission schemes, and improve its efficiency.

Key words: ordnance science and technology, 4-DOF, planetary gear transmission, scheme performance