Design and analysis of a novel 3-DOF configuration platform based on 2UPS/RU parallel mechanism

In this paper, a novel three degree of freedom configuration platform is presented based on the 2UPS/RU parallel mechanism, which serves as an end-effector for industrial robots, enhancing their workspace and flexibility in confined areas. Utilizing mechanism topology theory and screw theory, we calculate the degrees of freedom and coupling of the 2UPS/RU parallel mechanism. Additionally, the inverse kinematics equations and the velocity Jacobian matrix for the platform are also established. The correlation between the workspace and the structural parameters of the mechanism is expounded, and the dexterity performance index within the workspace is characterized based on the Jacobian matrix. Furthermore, a compactness index is devised to evaluate the relationship between the workspace of the 2UPS/RU parallel mechanism and its structural dimensions by analyzing the platform’s motion characteristics. The structural parameters of the 2UPS/RU parallel mechanism are optimized using the genetic algorithm, with the compactness index parameter and the global dexterity index serving as the objective functions. This optimization results in a 116.92% increase in the compactness index of the configuration platform and an 11.14% improvement in the global dexterity index.