Hercules attitude processor (HAP)

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Virginia Tech


The design and analysis of a microprocessor-based gyro attitude data processing system used to geolocate natural phenomena from space was performed. Operational software was written and a HERCULES Attitude Processor (HAP) unit was built and tested.

Strict adherence to worst-case timing design criterion was a prime hardware design consideration. Weight, volume, and power requirements were also addressed. Redundancy was included for critical time maintenance functions. Hardware performance and accuracy was calculated and measured.

Operational software was written to control the functions of the HAP unit. Algorithms were written to accurately process the high speed gyro attitude data. Data communication between subsystems in the HERCULES system was controlled by the software. Subsystem configuration, operating modes, self-testing, and resource management was performed by the operational software.

Testing was performed on the HAP unit and operational software. Hardware and software performance was analyzed and is presented.