Force Dimension LLC: OMEGA haptic device

Citation

(2004), "Force Dimension LLC: OMEGA haptic device", Sensor Review, Vol. 24 No. 1. https://doi.org/10.1108/sr.2004.08724aad.003

Force Dimension LLC: OMEGA haptic device

Force Dimension LLC: OMEGA haptic device

Keywords: Haptics

Over the last decade, many prototypes and commercial haptic devices have been developed, but very few have offered a convincing and elegant solution to the haptic community. Even worse, these solutions are not only expensive but also have serious limitations when it comes to the actual amount of force that the device can convey, or the size of its workspace.

To evalutate the performance of a haptic device, it is necessary to understand some of the most important design criteria:

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  the mechanical system should display low inertia, high stiffness with low friction (force threshold) and no backlash (machanically induced force discontinuity).

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  the force actuators should enable back-drivability, offer a high dynamic range, a sufficient maximum force, a sufficient force output resolution and sufficient force and torque precision.

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  the position sensors need to have a good resolution.

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  the local control loop must have a high frequency (typically > 1kHz) to ensure that vibrations are undetectable to the human hand and that control stability is achieved at the desired contact stiffness.

Over the past couple of years, Force Dimension LLC, a Swiss company that specializes in the design of cutting-edge haptic devices, has come up with innovative solutions not only to improve the state-of-the-art in haptic hardware technology, but also to cut down on the costs of such tools. A spin-off from the Swiss Federal Institute of Technology in Lausanne, Force Dimension stays in close contact with researchers. This unique combination of expertise has lead to the development of the delta family of haptic devices.

The most noticeable feature shared by all the Delta Haptic Devices is the parallel mechanical architecture (see Plate 3): based on the patented delta robotic structure, this combination of light-weight aluminum bars and strong, static actuators provides a significant reduction of inertia when compared to serial architectures, thus improving the device dynamics. Furthermore, parallel mechanics dramatically increases the stiffness and robustness of the structure, leading to what is probably the strongest, most convincing point-contact haptic solution at present.

Plate 3 Delta Haptic Devices have parallel mechanical architecture

Another feature of the delta family of haptic devices is its user-friendly software interface. By distributing the processing between the electronic controller and the computer, the Delta Haptic Device API (DHD-API) proves to be both easy to use and very versatile. The electronics of the device handle all the fast, real- time processing that is critical for high-fidelity haptic rendering, while the software API can be used on non-real-time OSs such as Microsoft Windows, Linux and Apple's OS-X. For the programmers, it takes as little as four lines of C code to integrate a Delta Haptic Device with their application. For the researchers, the DHD- API lets the user access all the low-level features such as encoder readings and motor commands.

The latest addition to the delta family of haptic devices, is the Omega Haptic Device, which will be launched in January 2004. The Omega device renders forces up to five times higher than the competition and is the first commercial haptic device to ever implement the USB 2.0 standard. Its stylish and compact design offers an elegant solution to computer desktop applications. Perhaps most importantly the Omega has been designed to provide outstanding haptic rendering at a price that can fit into the budget of any research laboratory.

For further information, please contact: Sébastien Grange, VP of Product Management. Force Dimension LLC, E-mail: info@forcedimension.com