CamCube Interim Review 2 ASEN 4028 – March 15, 2004 Sam Baker Tom Freestone Brian Madge Brian Roberts Steve Pfau Jen Uchida

Overview Project Summary Resolved Issues Design Summary Current Issues to be Resolved Schedule Progress Budget Progress

Project Summary Multi-year goal –Design a pico-satellite around the CubeSat program guidelines. The satellite will be launched from the shuttle and orient itself in order to take pictures of the heat tiles with an onboard camera. Current year goal –Develop an attitude control system that will orient the satellite and keep the on board camera steady for pictures.

Project Summary Reaction Wheel –Testing in a single axis –Possibility of testing in two axes Dual Disk testing apparatus –Applied torque from the reaction wheel 3-axis Gimbal –2-axes will be locked for the single axis test –Measuring stability, slew rate, response to applied forces

Resolved Issues Machining Time –Most parts complete –1 part left to fabricate Battery mounting bracket

Design Summary – Cube

Design Summary – Dual Disk

Current Issues Load cell –Miscalculation of force from desired torque numbers –Ordered new load cell (came in this morning) –Each test only takes about 8 seconds Increase output voltage to the motion controller by 1mV every millisecond

Dual Disk Results

Wrong load cell Noise –~5mV output –~15 mV noise –Wobble in reaction wheel –Torque from wire

Current Issues Wobble analysis –Nutation angle,  –Shaft displacement from center of RW –Non-uniform mass Nutation –Number of precessions per revolution –Negative => retrograde

Budget Progress – Estimated Budget

Budget Progress – Actual Budget

Questions?