Experimental Sensor CharacterizationAuthor(s): Sands T
Spacecraft use accelerometers to measure acceleration (changes in speed), so the spacecraft can know things like when it has fired its engines long enough. Thus, accurate modeling and characterization of the accelerometer are very important features of any space mission, especially since it involves fuel consumption (currently an unreplenishable asset in space). Accelerometers are particularly useful for guidance, navigation and control. Simple control algorithms begin by using the governing physics expressed in mathematical models for control, but usually more advanced techniques are required to mitigate noise, mismodeled system parameters, of unknown/un-modeled effects, in addition to disturbances. This research describes methods utilizing LabVIEW software and a myDAQ device, a low-cost data acquisition (DAQ) device that gives students the ability to measure and analyze live signals from Bosch BMA145 accelerometers, both signals and noise. Accelerometer characterization is key to the success of any space mission. This tutorial instructs the reader how to setup the experimental test hardware and characterize an accelerometer and then proceeds to analyze the noise, permitting the utilization of the accelerometer for free fall utilizing a novel algorithm that is a natural extension of the experiments used for accelerometer characterization and noise analysis.