Preliminary structural design of PANCAM, a bifocal panoramic camera for planetary observation

High-performance imaging systems play a fundamental role in space and planetary observation. Traditional cameras require actuators coupled with movable elements to scan large scenarios and overcome their limited field of view. Extra equipment increases the mass budget and the instrument complexity, as well as the risk of failure. Panoramic optics constitute a valid solution to enhance the imaging systems robustness while enlarging the camera field of view, all with a single compact device. In this paper, the feasibility of employing an off-the-shelf optical system based on a hyper-hemispheric panoramic lens for planetary observation has been assessed. In particular, the supporting frame of the aforementioned optical system has been designed to withstand a general space environment, i.e. temperature variation between -120°C and + 120°C, and considering loading during launch. A design solution is proposed, resulting from a kinematic-like mounting system to safely endure the thermal environment. In order to validate the obtained design, a mockup has been manufactured, assembled, and tested in a representative mechanical environment, exhibiting good agreement with the dynamic behaviour predicted by the developed numerical models.