Novel Solutions for CubeCat Attitude Determination and Control Systems Using PCB Magnetorquers and Low Power Control Solutions

Satellite attitude determination and control systems (ADCS) can be large, heavy, and expensive relative to a CubeSat’s size, weight, and cost requirements. We have developed a compact, low-mass, inexpensive ADCS prototype suitable for a student-class 1U CubeSat. We utilize three enabling technologies to reduce size, weight, and power (SWaP): 3-axis low-profile printed circuit board (PCB) magnetorquers, a basic sensor package, and computationally efficient control. The PCB magnetorquers are mounted on the exterior of the CubeSat frame to conserve internal volume for spacecraft electronics and payload. Attitude is determined by infrared horizon sensors and a magnetometer. The control algorithms utilize computer vision principles optimized to run on a low-power, inexpensive STM32 microprocessor. The ADCS uses a standard UART interface and PC-104 connector compatible with many standard CubeSat flight computers and other components. We have demonstrated a full ADCS system that occupies less than 0.1 U, consumes less than 0.50 watts in active actuating mode, weighs less than 100 grams, and costs less than $1,500 to fabricate. The ADCS design provides budget-constrained small spacecraft developers access to previously unavailable attitude control capability.