H-Delta: design and applications of a novel 5 degree of freedom parallel robot

Abstract

This thesis presents a new parallel 5 DOF robot called the H-Delta. The H- Delta adds 2 degrees of freedom (DOF) to the traditional Delta robot in a novel way, adding functionality and versatility. Importantly, the rotational DOF are decoupled, independent of the translational movement. This thesis begins by covering the necessary background the H-Delta is built upon, and then describes the structure of the H-delta and how it improves upon the state-of-the-art. The kinematic analysis of the H-Delta covers the inverse kinematics, Jacobian matrix derivation, stiffness, and dexterity. To provide a reference to an existing structure the H-Delta is compared to the benchmark Stewart Platform. A Dynamic analysis is performed by formulating the dynamic equations of the H-Delta using the Lagrangian method. The results of the dynamic calcu- lations are verified with a dynamic simulation which also acts as a test bed to develop control systems. A multi-objective optimization of the H-Delta is presented and using the in- formation accrued to this point an initial prototype is designed and constructed to verify the H-Delta structure. With the knowledge of the strengths of the H-Delta gained from the analysis and prototype, select applications are presented where the H-Delta best lends its strengths to the application. The H-Delta is mounted on a UAV to survey and interact with its surroun- dings. The prototype can use an on-board camera to track the position of an objective on the ground and center the gripper over it. When the UAV gets close enough, the H-Delta reaches out and automatically retrieves the object. When flying around, the H-Delta stabilizes the movement of the end effector, reducing acceleration. The prototype movement is measured and the results show that the end effector is accurate to within 3mm and the rotation is accurate within 0.5 degrees.