According to Division Ltd’s managing director, Charlie Grimsdale, Virtual Reality has the potential to be the technology from which the bionic man could be created. A three-dimensional interactive graphics environment in which the user must be fully immersed, virtual reality is an audio-visual representation of the world, where objects can be handled and manipulated in real time and real space, with potential applications in micro-surgery, molecular modelling, architecture, interior design, flight simulation and safety training. Says Grimsdale, virtual reality is an exploration tool; it is not about re-creating reality. Intrigued by some of the claims made recently by Division, Computergram took time out to visit the company at its small, converted country-cottage offices in the sleepy little village of Chipping Sodbury, Bristol. Division was founded two years ago by Grimsdale, from Perihelion, and Phil Atkin, Stephen Ghee and Ray McDonnell from Inmos International Plc. Chairman of the company is Iann Barron, the founder of both Computer Technology Ltd and Inmos (CI No 1,049). Division started life as a consultancy in parallel processing, and it was from this base that it discovered and took on the challenge of virtual reality. The company came across the concept at the Siggraph computer graphics show in 1989 and, fired by the potential the technology presented, the Division engineers decided that what virtual reality needed was parallelism.
Equipment
Division now makes a compute engine – a parallel processing box, and system software. It buys in its peripherals from other manufacturers. These include the hyped EyePhone, made by Redwood City, California-based VPL Research Inc; the Data Glove, also made by VPL Research; alternative boom mount displays, as made by Fake Space Labs Inc, Menlo Park, California; tactile data gloves, by Manchester-based ARL Advanced Robotics Ltd; and a three-dimensional audio system, by Crystal River Engineering Inc, Groveland, California. The EyePhones contain two small liquid crystal displays, or pocket televisions, with lenses in front – one for each eye. These are strapped over the head and are pretty heavy. On top of this helmet is a magnetic three-dimensional position tracker, developed by Vermont-based Polhemus Inc. This tracks the user’s movement in space. Data gloves are made of fabric with optical fibres stretching over the knuckles, monitoring changes in hand positions, thus enabling the user to pick up virtual objects. Tactile gloves, which to date work only in conjunction with data gloves, use small bladders that inflate with air, the pressure giving the illusion that the user is physically holding an object. Says Grimsdale, the peripherals will develop very quickly, so that the heavy headset, for example, may be replaced by a pair of three-dimensional goggles. ProVision, Division’s parallel deskside virtual reality system, is a multiple instruction multiple data machine based on a 19 rack format. A number of processing clusters can be plugged into the system to provide the required functionality – each autonomous cluster being dedicated to a different task, such as audio synthesis, visual image generation, body tracking and gesture recognition. The clusters are each controlled by one or more Inmos Transputers. The system is scalable – clusters of Transputers, Intel 80860s or equivalent processors can be added as the complexity of the modelled environment increases; ProVision also acts as an advanced three-dimensional terminal to existing hosts such as the Sun Microsystems Inc Sparcstation or MS-DOS microcomputer, which the system supports already.
By Sue Norris
For super-processing power, there is no reason why the system couldn’t be connected up to a Cray, although software support for this is not yet available. The applications development and operating environment is provided by dVS, Division’s distributed virtual environment system based on a client-server architecture. Currently dVS sits on top of another minimal operating system, and is to be converted soon to Unix. C
entral to the dVS environment is a C-based development toolkit consisting of the object-oriented Virtual Environment Control Interface, which supports the management of the complex objects, whose many attributes include colour, dynamics, sound, and collision properties. After following all the hype surrounding virtual reality, trying out Division’s demonstration proved something of a disappointment. Expecting to be totally absorbed in the virtual world to the point of disorientation, the only disorientation I felt was a slight feeling of nausea brought on by the gritty appearance of the graphics, and the pronounced time-lag between me moving my hand – clutching a joy-stick at arm’s length – and the reaction of the on-screen arrow which represented my hand. If I had been a brain surgeon directing a robot arm in the act of a discrete micro-op, then the patient would have seen better days. To be fair, the technology is still very much at the development stage, and has some way to go yet before it realises its full potential – meanwhile, it is easy to appreciate that the technology does have potential. The time delay, Grimsdale explains, is inherent within the tracking system, which currently has a low sample rate of 30Hz. There is also a lag within the renderer. This, he says, will be improved with time. So will the graphics, and the resolution of the displays. More work needs to be done also in the area of force and tactile feedback. Speech control is another feature which may be integrated – instead of picking up objects, users will be able to direct their manipulation verbally. Among Division’s customers are the University of Eindhoven, which is using ProVision to design a futuristic house – researchers are designing the interior using AutoCAD on a Sun Sparcstation, then convertingthe graphics for ProVision, using Division conversion tools, so that they can walk around in it and check that doors, for example, don’t block out windows, and that cupboards are not out of reach.
Conversion
The conversion process involves writing code for ProVision that will place the AutoCAD-designed objects in three-dimensional space – Division provides all the necessary help with this process. Manchester-based Advanced Robotics Ltd’s research centre is using ProVision in tele-robotics, which Grimsdale reckons could be a major area for virtual reality. Tele-robotics involves placing a human in physical control of a robot in a moving environment. In a nuclear plant, for example, a robot could be controlled interactively from a remote location, for critical maintenance operations. Division’s US distributor, Palo Alto, California-based Telepresence Research Inc – a software engineering house founded by two people from NASA – has installed ProVision in a virtual reality laboratory. And NASA’s Ames Research Lab is using virtual reality to visualise the airflow across the Space Shuttle, while the Johnson laboratory is using it to study its space station. Interest in the technology, according to Grimsdale, is coming mainly from the areas of medicine and pharmacy, for experiments in reversing medical procedures and drug modelling; computer-aided design and architecture; training and simulation; also the technology has implications for education – the student can learn about science by experience, for example – though UKP45,000, the price of a complete virtual reality system, is still a lot for schools to afford. Looking to the future, Division sees virtual reality technology being incorporated in personal computers as the latest in user-friendly interfaces. Even the likes of IBM and DEC are experimenting with the technology; Priestly reckons that soon most large information technology companies will go into virtual reality research.
