1993 VR Conference Proceedings

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The Dart Target System
Virtual Reality for the Physically Challenged

Elissa J. Tivona, MA
David A. Young, PhD

Introductions

Elissa Tivona - Remember the 80's ... remember interactive videodisc? Does IVD really qualify as old technology? Or has it simply "morphed" into multimedia and now one step further into Virtual Reality? These are just several of those penetrating questions which keep techno-junkies like David and myself puzzled about how to make a living for decades. As pioneers in interactive video, I remember heralding the marriage between the microprocessor and the video player as a milestone of immense proportions: with welding simulators and interactive "resusci-Annies" for CPR training emerging through the magic of IVD wizardry. Even today, with the advent of data gloves and helmets which introduce users directly into totally digital environments, the old classic IVD applications hold their own in respectably simulating reality. And isn't that what this legendary oxymoron, virtual reality, is all about? Is it real, or is it virtually real?

So before I launch myself into yet another quandary on whether or not I should reprint business cards, I want to bring the focus back to where it belongs - the application itself (regardless of how it's labeled). To do this I'll share my recent work on the Dart Target System. In brief, the Dart Target System is a bowhunting simulator, giving all archers, including the physically challenged, an opportunity to experience the thrill of shooting live game in their natural habitat.

David Young - You might wonder where my interest in the system comes from: given the level of my disability, I cannot make use of the Dart Target System as it is currently configured. However, this past winter, looking for a recreational outlet to help cope with the loss of a family member, I decided to try "sit-skiing" at Winter Park, which at least the way I do it, is not for the timid. Once again, I was reminded of the dearth of recreational options for disabled persons and myself in particular. When Elissa began discussing her work on the Dart project, I was reminded that an important recreational release for me prior to my injury had been target shooting with both bows and firearms. (I was captain of my high school rifle team and belonged to the Framingham Sportsmen's Association.) I became intrigued by the real potential in the Dart idea for expanding recreational opportunities for the disabled, and I became involved in the technology to see if we can make special adaptations work.


The Technology:

At the heart of the Dart Target System is standard Level III interactive videodisc technology, with a twist: the input device is in fact an actual bow and arrow! Although the System might be considered a grand-daddy in today's world of fully digital virtual reality systems, the product is specifically designed as an affordable, turn-key system which can be easily installed in any existing indoor archery range or rehabilitation center, today!

It includes a laser videodisc player under the control of a 386 computer, a video projection system, and a target face complete with an extremely accurate sensor system.

Dart software is designed to randomly access any one of the sixty wildlife scenarios recorded on the system videodisc. As one or more archers wait in a darkened 20-yard tunnel, the image of a game animal appears on the screen. In this actual footage filmed in the wild, the animal moves in and out of vegetation, simulating the very conditions and decisions a hunter encounters in the field. To succeed, the archer must choose the proper angle and hit the animal in a specific "kill zone," defined by the actual location of the animals vital organs. Archers typically use their own bows and arrows, with blunt tips supplied by the range operator.

Once the wildlife scenario starts to play, the archer draws and, just as in a real hunting situation, must wait for a good shot opportunity. If he waits too long, the animal moves off the screen and the system branches to a new animal scenario. He scores nothing. If he shoots, the Dart Sensor System, operating like a giant touchscreen, picks up the shot as soon as his arrow hits. The computer then pauses the video, and overlays a circular target outlining primary and secondary kill zones and showing the shooter the precise location of his shot. A direct hit in the primary kill zone scores a perfect 10 points, a hit in the secondary zone earns 5. Everything else is a zero. The computer instantaneously calculates the shooter's score and displays it on the screen.

The software is set-up to operate in several modes. Random selection mode allows up to 6 participants to shoot at a time. During his turn, an archer may have the opportunity to shoot elk, deer, bear or turkey off disc #1; or moose, caribou, antelope, bighorn sheep or several small game off disc #2. Serious archery enthusiasts can compete in tournaments, using the system's League mode. In this mode, each shooter gets a total of thirty shots (five sets of six arrows each). The computer keeps track of each shooter's score, giving results at the end of each set and the round. Dart is looking forward to nationwide competitions including archers throughout the entire Dart dealer network.

The system components which make this realistic hunting simulation possible are really quite simple. The 386 communicates with a standard video laserdisc player. The laserdisc provides several important advantages over videotape. First, each frame of video on a CAV disc has a discreet address, making random access branching from scenario to scenario possible and instantaneous. Second, a laserdisc player can "park" or pause on a single frame of video without any damage to the medium since there is no contact between the player and the videodisc, where as with tape the video heads are constantly spinning and making contact with the tape, which can lead to eventual degradation of the video program.

Finally, in order to display the "kill zones" after the shot is performed, the analog video from the laserdisc is overlaid with digital graphic information generated by the computer. The video and the graphic information are simultaneously relayed to a standard video projector which is located twenty feet from the screen. The screen is equipped with a proprietary sensor system which completes the loop back to the computer, registering each arrow hit that occurs.

Another handy Dart Target System peripheral is the printer, giving archery range owners a host of options ranging from providing score sheets to league participants to publishing mailing lists of system users. Finally, the Dart Target System includes a modem which allows Dart International to communicate directly with all systems in the field. Dart uses this network to download all software upgrades, for example, the control software for new videodisc releases. These, by the way, are published quarterly, allowing ranges to compile a library of wildlife challenges for customers.


The Future:

So, is what we've just described virtual reality? Well, it is for the dozens of disabled shooters who have sampled the Dart Target System. Frequently, physical disability is the ultimate frustration to an avid sportsman or woman, but through the technology, these individuals can enjoy experiences which appeared unattainable: the adrenalin rush and critical thinking which accompany a hunt. Additionally, David's participation and this Conference are helping Dart open a dialogue on how to make the Dart Target System even better suited for the physically challenged - how about specially equipped blow guns for quadraplegics?

Is there a real market for this particular VR application? Dart's experience says yes! For the immediate future, we are completing over 70 installations which are on order following the introduction of the Dart Target System at two trade shows in January. Some additional plans for the remainder of the year also include creating an animated target disc for children and other non-hunting system users; and the development of interactive videodisc training to be delivered at dealer networks on topics like shot placement and shot selection, bowhunting for the novice, and bowhunting safety. Furthermore, we are looking toward expanding the system's capability for use with projectile devices such as shotguns and other firearms in the year to come, opening up a still bigger market beyond archery.

Frankly, at Dart, we've stopped worrying about what we call the technology set behind the application, as long as dozens of range owners and others from coast to coast continue to order system installations. The bigger message is simply that success in virtual reality parallels success in any other form of production. First, be very clear about functional and marketing objectives, next be innovative in designing a product to meet them. Last - call it anything you want.

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