Automated Dynamics Data Post-Processing System for Tumbling Aerodynamic Body

Presenters/Authors(s)

Samuel Sutler, Nathaniel Michek, Wade Huebsch

Abstract or Description

Data acquisition and processing for the use of modeling aerodynamics can be an arduous task which requires the coordination of wind tunnel testing, computational fluid dynamics, and flight testing. Due to the physical constraints of wind tunnels and computational limitations of CFD, flight testing is the best means to characterize the complex 3-axis rotational dynamics of a tumbling aerodynamic body. Because of this, a Vicon motion capture system of more than thirty cameras was constructed to capture the position and attitude data of a sub-scale body throughout the ballistic trajectory. The current task is to implement an existing data processing scheme developed for data collection with high-speed cameras to integrate directly with the Vicon system through a series of MATLAB and Python codes which automate the transfer of Vicon’s recorded data and converts them to velocities, accelerations, body rates and additional key parameters in real time. The developed code uses Vicon’s DataStream SDK to transfer start and stop commands and record data to MATLAB at up to 600 fps with a 2% frame drop rate. The processing results in a 141-column matrix with data shown at the frame rate recorded by the Vicon system. Visual graphs of some key data generated throughout the code will give an immediate indication of the flight test’s behavior. Initial results indicate most tests can now be processed automatically in near real time allowing the user to make changes to the launching apparatus and data collection procedures to improve data quality on subsequent tests.