PMD Based Mobile Node Position Monitoring

Abstract

In this paper, we present first simulation results of the 3-dimensional, non-scanning, and non-coherent PMD (Photonic Mixer Device) imaging sensor to monitor the complete 6 degrees of freedom (DoF) of a mobile sensor node. The varying pose values of the node are measured directly from the 3-dimensional image sequences. As with a 3-D laser range finder, the system estimates 3-D position of the given markers with respect to the sensor node coordinate frame in real-time. The 3-D position of a minimum set of three markers fixed on the mobile node coordinate system is tracked by the PMD camera at a high frame rate to estimate the full 6 DoF of the moving node. The PMD does not have moving parts. The range of the sensor is a function of the modulation frequency of the transmitted light. In this paper a non- ambiguous range of 7.5 m at 20 MHz was considered in order to match the specifications of the existing PMD prototype. The pose estimation algorithm is a closed form solution and has no iterative loop, therefore the update rate is high and close to the sensor 3-D data acquisition rate.