Dynamic Modeling of a Class of Parallel-Serial Mechanisms by the Principle of Virtual Work

Dynamic modeling of parallel-serial mechanisms (P-SMs) is a challenging task. Aiming at some shortcomings of the existing dynamic analysis methods of P-SMs, this paper systematically establishes the complete dynamics model of a class of P-SMs by the principle of virtual work. Firstly, the position of the P-SMs is analyzed by combining the Euler method and the Denavit–Hartenberg method. The vector chain method dedicates each rod's velocity and acceleration equations in the P-SMs. Then, the parallel mechanisms and the serial mechanisms (SMs) are regarded as a whole, and a complete dynamic model of a class of P-SMs is established by the principle of virtual work. Finally, typical P-SMs are taken as examples to verify the generality and effectiveness of the model. This model introduces the principle of virtual work into the dynamic analysis of the SMs for the first time, and the obtained complete dynamic model has a clear physical meaning, which can provide a basis for follow-up studies.