Slip Ring Electrical Anomalies Found After Protoflight Vibration Testing

摘要

Following protoflight component testing of a Solar Array Drive Assembly (SADA), post-test electricalrnmeasurements revealed shorted circuits caused by slip ring brush displacement. Initial investigation,rndisassembly and analysis suggested the root case was related to insufficient preload in an axial biasrnspring constraining the slip ring rotor. Successful rework and re-test supported this conclusion. However,rnlater tests of similar hardware for a subsequent program resulted in a comparable electrical anomaly.rnOriginal investigation results were reviewed and found to still be valid. However, additional contributingrnfactors were identified that led to the reoccurrence of the anomaly. This paper explores the discovery,rninvestigation, analytical approach, and ultimate resolution of a SADA slip ring anomaly.