DYNAMIXEL servos simplify wind tunnel testing

Dear friends,

I am the founder of a project to create an Open Source, mostly 3D printed air data sensor and display for small airplanes. This is for fun and education, but also to improve safety: By being better aware of how an airplane is moving through the air, pilots can avoid common flubs that cause accidents.

Wind tunnel calibration for this project was done by a team at Wichita State University, using the Walter H Beech wind tunnel. This album shows the air data probe being calibrated in the wind tunnel, and the final report details the findings. The testing team at Wichita consisted of:

  • Matthew Anderson
  • Konstantin Ganchev
  • Matthew Schmid
  • Riley Ziegler

and involved the supervision of:

  • Dr Brandon Buerge, faculty supervisor
  • Vijay Matheswaran, lab manager

We used a DYNAMIXEL 2XL430-W250-T servo to move the test article while in the wind tunnel. The DYNAMIXEL range is perfect for this application, as it provides an “out of the box” motion control solution without messing with steppers, limit switches, or hobby-grade RC airplane servos. We tested the angular accuracy and found it beyond our ability to measure with a workshop protractor, and therefore more than enough for aerodynamic testing.

A previous iteration of this work involved a pair of DYNAMIXEL AX-12A servos mounted on the end of a PVC pipe on a Toyota Prius as shown here. Alas, the airflow on the ground is way too turbulent for real data acquisition! Wind tunnels are great!

Ihab Awad

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This project won the EAA’s Founder’s Innovation Award twice: in 2016 and 2021.

Ihab Awad

For more information, see this summary; a video; the project website, and our Github repo. The sensor works by using air pressures measured on the surface of a plastic “ball” shape to determine the air flow direction and magnitude.

Ihab Awad