Session
Frank J. Redd Student Competition
Location
Utah State University, Logan, UT
Abstract
There is great interest in high precision attitude control of satellites, in particular for missions that operate payloads with stringent pointing requirements. Reaction Wheels (RW) are an integral part of a satellite's Attitude Determination and Control System (ADCS). However, a drawback of using RWs is that due to imperfections such as rotor imbalance and bearing defects, RWs are a source of micro-vibration. These phenomena can lead to internal disturbances which in turn may lead to degraded mission performance.
Quantifying the micro-vibration generated by RWs is a critical and time intensive process. A two-step process to verify and characterize RW micro-vibration performance will be presented in this paper. The verification is performed by conducting a short-form test in a single axis using a Laser Doppler Vibrometer (LDV). The characterization is performed by conducting a long-form test in all axes using a Multicomponent Force Dynamometer. Both tests allow for the determination of a RW’s imbalance and noise profile which can be evaluated against a pass/ fail criteria.
A challenge associated with scaling production is verifying wheel micro-vibration performance in an efficient manner, while maintaining a high degree of product assurance. Quality control limits and correlation analyses were conducted to aid in developing a more efficient process for RW verification and characterization. A framework for the refined two-step process will be presented alongside a case study to identify acceptable micro-vibration performance, using Sinclair Interplanetary’s RW-0.06 product. The methods presented here can be used within the small satellite community to better understand and predict the micro-vibration performance of reaction wheels.
Empirical Methods for Reaction Wheel Micro-Vibration Verification in a Production Environment
Utah State University, Logan, UT
There is great interest in high precision attitude control of satellites, in particular for missions that operate payloads with stringent pointing requirements. Reaction Wheels (RW) are an integral part of a satellite's Attitude Determination and Control System (ADCS). However, a drawback of using RWs is that due to imperfections such as rotor imbalance and bearing defects, RWs are a source of micro-vibration. These phenomena can lead to internal disturbances which in turn may lead to degraded mission performance.
Quantifying the micro-vibration generated by RWs is a critical and time intensive process. A two-step process to verify and characterize RW micro-vibration performance will be presented in this paper. The verification is performed by conducting a short-form test in a single axis using a Laser Doppler Vibrometer (LDV). The characterization is performed by conducting a long-form test in all axes using a Multicomponent Force Dynamometer. Both tests allow for the determination of a RW’s imbalance and noise profile which can be evaluated against a pass/ fail criteria.
A challenge associated with scaling production is verifying wheel micro-vibration performance in an efficient manner, while maintaining a high degree of product assurance. Quality control limits and correlation analyses were conducted to aid in developing a more efficient process for RW verification and characterization. A framework for the refined two-step process will be presented alongside a case study to identify acceptable micro-vibration performance, using Sinclair Interplanetary’s RW-0.06 product. The methods presented here can be used within the small satellite community to better understand and predict the micro-vibration performance of reaction wheels.
