Can you feel the force?

Jon Excell explains how virtual reality is putting manual creativity back into the design process

The cry of sceptics – that human creative input will be usurped by processing power – could be silenced by cutting edge developments in haptic interfaces.

Enhancing interaction with a virtual environment by stimulating the sense of touch, haptics puts the user in control of a tool that acts upon this environment.

One of the most popular interfaces is SensAble Technology’s Phantom, which works alongside the company’s Ghost software. Looking like an angle poise lamp, the device has a pen or thimble for the user’s fingertip, which works like a `tactile’ mouse. Three motors, controlled by algorithms, provide the user with `force feedback’ by exerting pressure on the thimble, simulating the sensation of whatever the user is working with in the virtual world.

Applications for this technology vary considerably. For example, the Hothouse, a ceramic design centre in Stoke-on-Trent, has recently asked SensAble to help tailor haptic systems for use in the pottery industry. According to Hothouse manager, Andrew Briggs, the addition of the sense of touch to CAD will allow designers to work more intuitively – they will enjoy the advantages of CAD coupled with the sense of working with clay.

Until now, these devices have restricted the user’s interaction with the virtual world to the control of a single point, ignoring the geometry of physical tools. Now, MIT researchers, in collaboration with Suzuki, have developed a system that enables the user to touch virtual environments with full 3D realism.

Suzuki’s haptic device combines with MIT software to simulate interaction between fully three dimensional bodies within the virtual environment, enabling any 3D solid to be used to probe the virtual environment. MIT’s research team is interested primarily in manufacturing applications, the first of which is for a system that creates machining tool paths for rapid prototyping. The user manipulates a tool in virtual space to “teach” the machine how to cut an object.

At $99, cheaper technology is available in the form of a mouse developed by Immersion Corporation. The `FEELit’ mouse generates physical sensations through a system of actuators which impart physical forces upon the mouse handle and restrict its movement on the pad.

While working alongside the graphical user interface, this technology should ultimately change the way everyone interacts with their computers. As the user moves the mouse, each encounter between the cursor and items on the screen can be `felt’. Immersion describes this as `pressure clicking’. Instead of using the traditional point and click process, the mouse simulates the sensation of a switch being pressed when the user `pushes’ against an icon.

To help the host computer, Immersion has given the mouse its own local processor, optimised for feel related calculations and cursor interactions. This technology has inevitably been welcomed by the games industry, and, as we write, manufacturers are excited about the Christmas launch of games specially tailored for use with a similar device from Logitech.

There is much that needs to be done to make these systems `fully realistic’, but the haptic community is continually improving on its attempts to approximate the feelings of touch in the real world.

Sensable Technology Tel: +1 617 621 0150

Immersion Corporation Tel: +1 406 467 1900