Abstract: A spacecraft includes a power train that includes a solar array, an electric propulsion subsystem, and a power conversion module. The power conversion module receives power from the solar array at a voltage, Vi; and delivers power to the electric propulsion subsystem at a voltage, Vo. The spacecraft is configured to operate at a varying distance, D, from the sun within the range of Dmin to Dmax, Dmax being at least 1.3×Dmin. The solar array is configured to deliver power to the power conversion module at a voltage approximately equal to Vo when the spacecraft is proximate to Dmax.

Abstract: Fast real-time rendering of a voxel-based 3-D object is achieved by constructing a surface voxel chain and using incremental vectors in describing positions of the chain elements. The rotations of all incremental vectors from a world space into a camera space are performed prior to a real-time imaging process, and the resulting rotations are stored in a lookup table. During the real-time process, only the information for surface voxels is stored and transformed; therefore, the required memory size for the 2-D imaging process is dramatically reduced, while the speed is greatly increased.