High-Force Display Capability and Wide Workspace With a Novel Haptic Interface

We present a novel haptic interface, named VirtuaPower, having a high-force display capability (FDC) and a wide workspace with a six-degree-of-freedom position measurement and FDC. The overall mechanism of VirtuaPower is designed based on a parallel pair of five-bar mechanisms supporting the end-platform. This novel mechanism enhances the high-FDC and overcomes the problem of small-size workspace, which are the pros and cons of parallel mechanisms, respectively. First, we present the conceptual design and prototype of VirtuaPower. Then, we formulate the forward kinematic and the constraint and space Jacobian. Using these formulations, we analyze two types of workspaces and FDC. In both analyses, VirtuaPower shows remarkable performances, especially in terms of its FDC, compared to other haptic interfaces having an equivalent size. In addition, we validate the static, step, and frequency responses of the force-display performance by performing experiments using the test bench of fixed end setup with a six-dimensional force/torque sensor. Finally, we evaluate the suitability of VirtuaPower as a haptic interface by realizing two types of virtual sphere walls and a virtual reality environment.