Robotics: Science and Systems VI

Passive torque regulation in an underactuated flapping wing robotic insect

P. Sreetharan and R. Wood


Recent developments in millimeter-scale fabrication processes have led to rapid progress towards creating airborne flapping wing robots based on Dipteran (two-winged) insects. Previous work to regulate reaction forces and torques generated by two flapping wings has largely focused on wing trajectory control. An alternative approach introduces additional degrees of freedom to the wing flapping mechanism to passively regulate these forces and torques. The resulting ‘mechanically intelligent’ devices can execute wing trajectory corrections to realize desired body forces and torques without the intervention of an active controller.
This paper describes an insect-scale flapping wing aeromechanical structure consisting of a piezoelectric bimorph power actuator, an underactuated transmission mechanism, and passively rotating wings. The transmission is designed to passively modulate wing stroke velocity to eliminate the net roll torque imparted to the airframe.
The system is modeled as having four degrees of freedom driven open-loop by a single power actuator. The theoretical model predicts lift-generating wing trajectories as well as a passive reduction in roll torque experienced by the airframe. An at-scale structure constructed using Smart Composite Microstructure (SCM) fabrication techniques provides experimental support for the theoretical model.



@INPROCEEDINGS{ Sreetharan-RSS-10,
    AUTHOR    = {P. Sreetharan AND R. Wood},
    TITLE     = {Passive torque regulation in an underactuated flapping wing robotic insect},
    BOOKTITLE = {Proceedings of Robotics: Science and Systems},
    YEAR      = {2010},
    ADDRESS   = {Zaragoza, Spain},
    MONTH     = {June},
    DOI       = {10.15607/RSS.2010.VI.002}