Development of Hybrid Drive Parallel Arm for Heavy Material Handling

This paper presents a hybrid cylinder/wire drive parallel arm.Its workspace is analyzed for the application of manipulating heavy materials in construction and ship building industries.The conventional Stewart platform and a multiple wire drive mechanism are compared and hybrid drive mechanisms are considered in analysis and designing.The total number of cylinder and wire is fixed to seven based on the force closure principle.The actuated cylinder force and wire tension are analysed based on the kinematics and statics formulated for an arbitary combination of cylinder and wire mechanism,then its work space is evaluated.An arm mechanism with three cylinders and four wires is proposed in the application of manipulating a precasting concrete board with 3x6x0.2(m) in size and 10(t) in weight