広い実作業領域を有する空間6自由度3-USR形パラレル機構の開発

―2自由度球面パラレル機構の運動性と剛性の実験的解析―

抄録

The 3-USR parallel mechanism which has large workspace has been proposed. Its input joints are three coaxial active universal joints. As this active universal joint, the 5-bar spherical parallel mechanism with 2 D.O.F. is adopted. Its optimal kinematic parameters are designed in consideration of motion transmissibility and two type (orthogonal type and coaxial type) of spherical mechanism are proposed. Prototypes of 3-USR parallel mechanism with two type spherical mechanism are manufactured and their accuracy and stiffness are investigated. It was found that the performance of 3-USR parallel mechanism with coaxial type are lower than its with orthogonal type, although their motion transmissibility are almost even. To design the spherical mechanism with high accuracy and stiffness with out experiments, the relationship among motion transmissibility, accuracy and stiffness are experimentally investigated.