Much effort within the field of robotics has been made to study and mimic the
agility of biological
flight. Emulation of bat
flight is particularly difficult, as
bats utilize numerous independent means of control of both their inertial and
aerodynamic characteristics to complete a variety of complex maneuvers. In
this thesis, we investigate the viability of enabling a reduced-DoF bat robot
to synthesize one such maneuver, inverted perching, by simultaneously and
directly optimizing both the configuration and the trajectory of the robot.
We begin with a minimal model of a
flapping
flight system. Noting that
longitudinal inertial dynamics represent the dominant behavior for the perching
of biological bats, we introduce a single additional degree of actuation: a
mass that may be shifted along the longitudinal axis of our system. We use
the Lagrangian method to derive the equations of motion for our model, and
then construct an augmented system where design parameters, namely linkage
masses, are decision variables that are constrained to a constant value.
We then reduce our optimization problem to an instance of the Direct Collocation
trajectory optimization method, and find the minimum-time perching
robot and trajectory. Our final configuration is able to complete the perching
maneuver on a similar timescale to biological bats, suggesting viability of the
reduced-DoF configuration.Ope
