ESA GNC Conference Papers Repository

The National Aeronautics and Space Administration (NASA) Satellite Servicing Capabilities Office authorized the delivery of a pointing package to be mounted on the end of the Special Purpose Dexterous Manipulator (SPDM) robot arm on the International Space Station (ISS). This DEXTRE Pointing Package (DPP) is composed of various attitude determination sub-systems along with an avionics package and provides attitude knowledge and the ability to inertially stabilize the DEXTRE arm through closed loop control on future missions. Payloads mounted on the DETRE arm for significantly increased Field Of View (FOV) away from the ISS will now have the stable platform required for precise science pointing operations. In addition, this allows exploration of autonomous capture of non-cooperative targets and the ability to service previously unserviceable spacecraft to extend on-orbit assets. In December 2010, Ball delivered an autonomous proto-flight model star tracker for incorporation into DPP. The DPP Star Tracker will provide precise attitude knowledge, and will be combined with a gyroscope to enable absolute precision attitude determination capability for science payloads collocated with DPP. This paper provides an overview of the design, development, and verification of the new Ball FT-701 CMOS Sensor Star Tracker. This star tracker is a combination of the Ball’s flight proven CT-633 body with new components developed under continuous Ball Independent Research and Development projects.