<title>New approach for combined bundle block adjustment and orbit determination based on Mars-94 three-line scanner imagery and radio-tracking data</title>

Abstract

The high resolution stereo camera (HRSC) and the wide-angle optoelectronic stereo scanner (WAOSS) onboard the Russian Mars-94 spacecraft provide permanent stereo capability using the 3-line stereo concept. The photogrammetric bundle adjustment, which includes the reconstruction of the exterior orientation of the 3-line scanner imagery, is the prerequisite for all subsequently derived products (e.g., DTM, orthoimages). In order to properly utilize the image information contained in the conjugate point coordinates and the orbit information contained in the radio tracking data, both data types have to be evaluated in a combined adjustment process. To this end, the conventional bundle block adjustment algorithm is supplemented by a rigorous dynamic modeling of the spacecraft motion to account for long-arc orbital constraints. The camera position parameters, which have been estimated so far at certain time intervals, are now replaced by the components of the spacecraft epoch state vector and trajectory model parameters that may comprise the Mars rotation rate or solar radiation pressure coefficients. The focus of the paper is given to the combined approach, its mathematical model, and its main advantages.