00k-Thorax: 2 DOF
completed Dec.2000, repaired March 2001


This design was the second attempt at creating a high speed flapping/rotating thorax with a rigid wing at
1.3X final scale. (The previous version used Thunder unimorph actuators and had quite small displacement.)
Initial operation with no wing showed widely separated flapping and rotational modes, with flapping at
about 100 Hz (?) and rotation at about 170 Hz (?) but at small amplitude. Adding the wing lowered the
flapping resonant frequency to about 70 Hz or so. Only by adding significant rotational inertia was it
possible to decouple the flapping and rotational modes. Coupling through the differential stiffness due
to the 12 um polyester was a significant problem. Large amplitude motion was limited by the
wooden inertia bar hitting the 4 bars.

1) Date of fabrication
        Dec. 2000
2) Dimensions of structure?

3) Actuation parameters
        two 16x3 PZT
4) Resonant Frequency 5) Amplitude of motion
        Q >6, DC motion ~ 0.2 degrees/volt? (both actuators driven)
6) Tests performed, duration of testing and mode of failure (if applicable) 7) Any other relevant info that you think would be useful 8) Status (Aug. 2001)
        functioning but large motion limited by inertia bar.