In 2007 some colleagues and I developed and tested a location-based augmented reality game known as TimeWarp Cologne. TimeWarp was a game that aimed to let people see what the City of Cologne would look like in the past and future. Below I present a brief overview of some of the guidelines that we developed, the full paper citation is below. If you have time you should look at the paper that we published as this contains much more information than is presented here. In 2010 the game was significantly modified based on our results and a new version tested, check out the Youtube Video for more information.
These are summaries of what appeared in the real paper, please consult the original text for more information.
- Understand Attention Allocation, certain augmented reality content e.g. animations will draw the users attention. Therefore be aware of how such content will draw people away from being aware of reality or other game based elements.
- Simplify Interaction Scheme, in common with general HCI practice avoid overly complex devices and interaction schemes. Keep the number of devices and interaction types to a minimum.
- User Safety, this should probably be the first item but avoid creating experiences near roads or other areas which may cause accidents.
- Design appropriate paths through the environment, make use of the underlying environmental structure when placing AR content. For example terminate certain journeys at interesting locations.
- Understand the Locale, understand what real world aspects are around e.g. cafes, bars or other areas which could be used within the game, or even avoided.
- Interaction with Others, where appropriate integrate non-game players into the experience.
- Seamful Design, check out the work of Chalmers on seamful design which basically argues that technical problems can be built into the gaming experience. For example, lack of GPS or 3G signal could play a part in the game.
- Use a combination of real and virtual objects, do not obsesses about using only virtual objects. Where possible and more appropriate try to use a combination of real and virtual objects. Also since writing the paper computer vision techniques have improved significantly and RFID is more readily available. These could be used to recognize objects or proximity to them.
- Provide a continuous experience, maintain a constant gameplay. It is important to avoid making people walk large distances between augmented reality content.
The work was partially funded by the EC and was part of the IPCity project. Special credit should be given to the following people who worked extensively in the project during this version of TimeWarp: Prof. Dr. Wolfgang Broll, Richard Wetzel, Anna-Kathrin Braun and Iris Herbst. Thanks to all those who are mentioned plus the many others who worked on IPCity. This publication also won “Best Paper” at MobileHCI 2008.
The guidelines presented above are drawn from the following paper and therefore should be cited as coming from:
Braun, A, Herbst, I., Broll, W., and McCall R. Timewarp. Interactive Time Travel with a Mobile Mixed Reality Game. In the Proceedings of Mobile HCI 2008. Amsterdam, Netherlands