A novel methodology to study the singularity of spatial parallel mechanisms

In this paper, a novel methodology to study the singularity of spatial parallel mechanisms is presented. With the theory of reciprocal screws, we make a thorough analysis of the kinematic screws of each branch mechanism. According to the physical meaning of the inverse screws of kinematic screws, we introduce the static equilibrium equations to gain a novel methodology to study the singularities of the dynamic mechanisms. Through the novel methodology, we obtain universal criteria that the mechanism will be singular.