Compatible reachable workspaces of symmetrical Stewart–Gough parallel manipulators

• Analytical methods to develop a compatible reachable workspace are presented.
• Characteristics of workspace boundaries are investigated.
• The equations for the whole workspace can be easily determined.
• The workspace can be developed within 10 min.

The reachable workspace of a 6-DOF parallel manipulator developed using most existing methods is not a compatible workspace, as some of its subspaces might not be reachable through a continuous motion starting from the initial assembly configuration. This paper uses simple geometric properties and some characteristics of workspace boundaries to develop a compatible reachable workspace for a symmetrical Stewart–Gough manipulator. Equations that generate the entire workspace boundary can be easily determined by solving direct kinematics at five specific points, and the compatible workspace of a symmetrical manipulator can be developed within 10 min using a personal computer.