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This question is a part of an online course (Mobility Data Management) that I am currently auditing. A part of the project is to implement a system that can predict user's future location. This kind of application has recently got some interests from database and mobile application developers.

This is the problem statement: Assume that we are given a road network G (V,E), the recent motion history (trajectory) T, and current instant velocity v of a user, a temporal duration dt, and (optional) a historical trajectory database D of other users’ movements. Our goal is to estimate user’s location after dt.

I found that the following paper has a good description about what a road network and the trajectory data is:

Does anyone has an idea on how to formulate a simple solution of this mobility awareness problem (predicting user's future location), and how to start the implementation (how you formulate the problem in an OOP way, such as: what classes are needed to represent the problem correctly).

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At its simplest formulation and over reasonably short distances and using a cartesian coordinate system, you can use the Pythagorean theorem to implement dead reckoning. Since it's an assignment, here are the formulas, the rest you can work out yourself.

distance = sqrt( (x2-x1)^2 + (y2-y1)^2)
slope = (y2-y1)/(x2-x1)
slope = tan(trajectory * (PI/180))

given those solve for (x2,y2)

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Thanks ! I am currently looking on the dead reckoning algorithm. This problem is not really an assignment though. This is a research question type, and I came to this discussion mostly due to my curiosity on GIS problem. – all_by_grace Jul 21 '11 at 14:31

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