Ultra-fast hybrid parallel manipulator

The principal goal of this work was to design a 6-DOF ultra-fast spatial parallel mechanism (accelerations of at least 2g). The goal was accomplished through the use of an architecture composed of a base connected to a mobile platform by three legs arranged symmetrically at 120 degrees. Each of the legs is composed of a 5-bar mechanism with two revolute joints at the base (the actuated joints which motorize the mechanism). The above figure illustrates the architecture of this manipulator.

Having chosen this architecture and correctly dimensioned each of the manipulator's parameters, a workspace of approximately 30 mm × 30 mm × 30 mm, rotational capabilities of ±25 degrees in any direction, and an excellent dexterity were sought. The evaluation of the inverse geometric problem and the velocity equations led to the jacobian matrix of the manipulator which was used in turn to calculate the dexterity for various configurations. The results obtained by evaluating the dexterity and considering the desired workspace, were used to dimension the different parameters of the manipulator. The mechanical design and selection of the manipulator components were then carried out to construct the prototype using the rapid prototyping technique.

The following video segments illustrate the prototype of the ultra-rapid parallel manipulator.