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With growth in data volume from space missions, interest in laser communications has increased, owing to their importance for high-speed data transfer in the commercial and defense fields, spaceborne remote sensing, and surveillance. Here, we propose a novel system for space-to-space laser communication, a very high-speed inter-satellite link system using an infrared optical terminal and nanosatellite (VISION), which is aimed at establishing and validating miniaturized laser crosslink systems and several space technologies using two 6U nanosatellites in formation flying. An optical link budget analysis is conducted to derive the signal-to-noise ratio requirements and allocate the system budget; the optical link margin should be greater than 10 dB to guarantee communication with practical limitations. The payload is a laser transceiver with a deployable space telescope to enhance the gain of the beam transmission and reception. Nanosatellites, including precise formation flying GNC systems, are designed and analyzed. The attitude control system ensures pointing and tracking errors within tens of arcsec, and they are equipped with a propulsion system that can change the inter-satellite distance rapidly and accurately. This novel concept of laser crosslink systems is expected to make a significant contribution to the future design and construction of high-speed space-to-space networks. [ABSTRACT FROM AUTHOR]

A new and patented polishing tool called Orthogonal Velocity field Tool (OVT) was built and its material removal characteristics from Chemical Vapor Deposition Silicon Carbide (CVD SiC) mirror surfaces were investigated in this study. The velocity field of OVT is produced by rotating the bicycle type tool in the two orthogonal axes, and this concept is capable of producing a material removal foot print of pseudo Gaussian shapes. First for the OVT characterization, we derived a theoretical material removal model using distributions of pressure exerted onto the workpiece surface, relative speed between the tool and workpiece surface, and dwell time inside the tool- workpiece contact area. Second, using two flat CVD SiC mirrors that are 150 mm in diameter, we ran material removal experiments over machine run parameter ranging from 12.901 to 25.867 psi in pressure, from 0.086 m/sec to 0.147 m/sec tool in the relative speed, and 5 to 15 sec in dwell time. Material removal coefficients are obtained by using the in-house developed data analysis program. The resulting material removal coefficient varies from 3.35 to 9.46 um/psi hour m/sec with a mean value of 5.90 ± 1.26(standard deviation). We describe the technical details of the new OVT machine, the data analysis program, the experiments, and the results together with the implications to the future development of the machine.