In the field of spatial orientation, the rotational parallel mechanism is widely used. While the existence of coupling brings about the parallel mechanism some difficulties in kinematics and dynamic analysis, the development of control system, and so on. This condition restricts the application fields and effects of the rotational parallel mechanism. Therefore, this paper proposes a novel 2-DOF (two degrees of freedom) rotational DPM (decoupled parallel mechanism). The feature of the mechanism is described and their movement form is analyzed with screw theory. The proposition of the novel rotational DPM will enrich the configurations of the parallel mechanism, and the contents of this paper should be useful for the further research and application of the rotational parallel mechanism.

This paper presents a novel parallel tri-axis force sensor with decoupled feature, and performs its performance analysis. Firstly, the structural characteristics of the parallel tri-axis force sensor are introduced and the stress distribution of each limb elastomer is analyzed. To measure the transformation relationship between the force and strain, the electric bridge is formed by pasting strain on the elastic-sensitive element. Then, the finite element simulation of the elastomer is conducted and performance analysis of the sensor is carried out, which shows that the parallel tri-axis force sensor is decoupled, linear and fully-isotropy. The sensor possesses good static performance and can meet the requirements of tri-axis force measurement in general industrial production. The contents of this paper riches the structure type of the multi-component force sensor and will be useful for the research and development of the parallel force sensor.