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High Performance Computation with Small Satellites and Small Satellite Swarms for 3D Reconstruction

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In this thesis research I discuss the design and implementation of 2 Earth observation Cube Satellites with a focus on the computational methods used and the design of their computer systems. The satellite computer systems are tested by simulating imaging of single view observations and multiview observations. Observations are simulated by imaging existing 3D models of the Earth's surface in 3D rendering software. A custom computer vision library, known as SSRLCV, is used to compute the final 3D models which are then compared to the ground truth. Restrictions, unique to the space environment, are mitigated with a specialized operating system, hardware, and software. Tests are run on the Nvidia TX2 and TX2i with timing, state, and power usage tracking. The Nvidia TX2i GPU accelerated SoC is modified for use in a Cube Satellite and is used as the platform for high performance onboard computation. The results show accurate 3D reconstruction of the surface of Earth feasible within 15 to 100 meters, depending on the camera system and altitude, while maintaining favorable power usage and computation time.
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... For the MOCI satellite, the dual USB ports allow access to the dual imager payload, allowing for full utilization of the GPU to carry out Structure from Motion (SfM) in orbit. 9 For other missions, however, USB could be used to interact with science instruments, external processors, or communication systems. ...
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