Using Determinism to Improve the Accuracy of Dead-Reckoning Algorithms

Collaborative Virtual Environments (CVEs) are real-time applications that require a high degree of responsiveness to maintain an immersive end-user experience. Because of latency and unpredictability in best-effort networks, dead-reckoning algorithms are routinely used to estimate the position of objects within the virtual space. Although traditional forms of dead reckoning work well for applications such as military simulation, they are less effective in intimate collaborative scenarios where the position of objects must be known with a high degree of precision. This paper is motivated by the observation that many events within the environment are deterministic: that is, they can be anticipated. We use the notions of determinism and event prediction to design a high precision dead-reckoning algorithm. This algorithm is intended specifically for use in intimate collaborative scenarios. We present experimental results that compare the performance of our high precision algorithm with that of traditional dead-reckoning techniques. We also discuss how determinism can be used to improve the distribution of other data structures used in collaborative virtual environments. † The authors wish to acknowledge that this work was carried out within the Cooperative Research Centre for Advanced Computational Systems (ACSys CRC), established under the Australian Federal Government’s Cooperative Research Centre Program.