Attitude Control System(ACS) d=- size of pixels (un 50 deg 1.5 deg Overlap f=focal length of optic 7x5.25 deg viewfinder 0.656 arcmin FOV f=38.8 mm 3.07x2.3 arcmin 0.288 arcsec f=5300470um Sensor 1 Active Electronic Compass Balancing System Sensor 2. Viewfinder #53155 ACS Actuator. Sensor 3 Reaction Rate gyro Wheel Chart: 8Chart: 8 Attitude Control System (ACS) Attitude Control System (ACS) Sensor 2: Viewfinder Sensor 2: Viewfinder ACS Actuator: Reaction Wheel ACS Actuator: Reaction Wheel Body r ate Body rotation Wheel speed + e τ Q d Q Sensor 3: Rate Gyro Sensor 3: Rate Gyro Sensor 1: Electronic Compass Sensor 1: Active Electronic Compass Balancing System Active Balancing System