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3D-coordinate producing systems have become very successful in the recent years. Aerial and terrestrial laser scanners are now ‘state-of-the-art’ to get information of the third and forth dimension and replace photogrammetric camera systems. Laser scanners typically have a very high point density, but because of their sequential mode of operation their shortcomings are both their speed of acquisition and their size.
The new range-imaging camera SwissRanger, developed by Centre Suisse d'Electronique et de Microtechnique SA (CSEM), is the first step to a follow-up generation of 3D-measurement systems and gets over the shortcomings and disadvantages of current photogrammetric systems and laser scanners. Because of its high-resolution with more than twenty thousand pixel, the created 3D-dataset even allows deducing geometrical information of the environment. The accuracy of the acquired distance is approximately 1 cm. Temporal resolution depends on various parameters like integration time, soft- and hardware. But five Hertz image sequences can be easily reached. Therefore, (near) real-time measurements are possible.
Several influencing parameters have been investigated in the calibration Lab of the Institute of Geodesy and Photogrammetry at the Swiss Federal Institute of Technology Zurich (Switzerland).
Besides first experiences and analysis of the data, acquired by the SwissRanger, a suitable approach for the calibration of such a system is to be considered and validated. First, a two-component calibration splits the sensor into a camera and a range measuring module. Both are calibrated separately with common known methods. The results of this calibration approach are compared to a newly developed single-step calibration. Hereby, the sensor is regarded as one single (black box) system. No assumption about the internal model is necessary. The results of the calibration are used for the improvement of the measurements.
Further, new applications for such a 3D-positioning system are presented. Besides the usefulness of the SwissRanger in car parking assistant systems, the applicability for an indoor positioning system is evaluated. The required accuracy and precision are focused.
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