Abstract:
According to Mars moving detection mission, three absolute positioning methods for Mars rover are proposed:wireless TT&C, image matching, position circling. For the wireless TT&C positioning, the orbit determination is first done, then the rover position relative to the orbit is determined by wireless communicating between two detectors, at last the absolute position of the rover is calculated. For the image matching positioning, the absolute position of the rover is calculated by matching the images during the landing process to the map of the landing zone with geographic information. For the position circling, the orientation of the sun and Mars gravity is measured by sensors at discrete moments, then with these measured results and ephemeris the absolute position of the rover is calculated. The three methods are analyzed and compared, and using advice is given according to factors such as precision, constraints, etc. To get the rover absolute position rapidly and accurately, position circling acts as the primary method to get the position, wireless TT&C method verifies the position, and image matching method revises the position.