COTS Detectors for Nanosatellite Star Trackers: A Case Study

In recent years, many imaging sensors for small satellites have adopted CMOS active pixel sensors. The Aptina MT9P031 in particular, has seen many adopters. This paper presents lessons learned from our experience integrating this detector with the Sinclair Interplanetary S3S Star Tracker. We present practical advice for handling and assembly and discuss strategies for maximizing image quality over the sensor lifetime. In particular, we characterize the noise characteristics from several units after high-energy proton testing, and consider a number of approaches to maintaining performance as radiation damage accumulates.