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Recovery of 3-D Motion of a Single Particle

In our previous analysis reported elsewhere, we have shown that 3-D velocity of a single point up to a scale factor could be recovered from its 2-D trajectory under the perspective projection. A batch method was used to solve the non-linear regression relation between motion parameters and measurements of projected position. Experimental results obtained from simulated images were given to demonstrate the soundness of this approach. In this paper, we extend our work along two directions. First, in order to make the estimation process meet the constraint of real-time computation, we derive the recursive approach to estimate the motion parameters. Second, we investigate the performance degradation due to two classes of model mismatch: parameter jumping and undermodeling. Then we propose the finite lifetime asynchronically triggered multiple model filter (FLAT MMF), as a solution. A number of simulations are conducted to illustrate the estimation performance degradation due to the model mismatches and the performance improvement as the proposed FLAT MMF is used.