Compact, Lightweight Isolation Platform (CLIP)

NASA has a critical need for improved bi-directional data transmission rates from a variety of spacecraft to Earth. NASA estimates that the current Mars to Earth transfer rate of 6 Mbps might be increased to 600Mbps using a laser comm (LC) system. Because the LC beam is less than 10 microradians wide and the Earth at apogee is 32 microradians wide, as seen from Mars, LC beam jitter caused by spacecraft base motion must be reduced to sub-microradian levels to enable beaconless optical beam pointing. To meet the need, NASA is seeking innovative compact, lightweight, space-qualifiable vibration isolation platforms for payloads massing between 3 and 50 kg that require less than 15 W of power and mass less than 3 kg that will attenuate an integrated angular disturbance of 150 ur to less than 0.5 microradians (1-sigma), from<0.1 Hz to ~500 Hz. ATA has a long track record of producing stabilized platforms to host small optical payloads. Building on a previous NASA SBIR, ATA now produces the stable platform used in NASA's LLST and LCRD programs. ATA will create a Compact, Lightweight Isolation Platform (CLIP) that could host the LC collimator telescope and provide a stabilized platform to prevent the 150-microradian spacecraft disturbance environment from reaching the LC terminal. Advances in the suspension flexure, the platform structure, and actuators will be required to meet the size, weight and power requirements. One challenging requirement is that an angular-motion sensor is required for the control system. Gyros exist that can measure adequately but they are too heavy, too large, and use too much power. ATA will develop a small, lightweight, nanoradian-class angular noise Capacitive Angular Position Sensor (CAPS). The sensor will have low power and high reliability, which ATA will demonstrate by producing TRL 4 prototypes in Phase I. ATA will develop the CLIP, a 0.5 microradian residual motion stable platform, in Phase II for programs like iROC.