Passive Autonomy: Hygromorphic Rotational Actuators
Design & Evaluation
More Info
expand_more
Abstract
Inspired by phenomena in the plant world, a
meteoro-sensitive rotational actuator is developed. The design
uses a hygro-active shell, whose water-based swelling is restricted
at selective locations to form a helicoid structure. The influence
of geometrical parameters on the performance is investigated
using a numerical analysis of various geometries, by looking at
resulting rotation and torque during this rotation. Prototypes
are built of five key geometries in the design space, to validate
the simulations and to investigate the real-life behaviour
of the design. These prototypes are submerged in water to
investigate their deformation, after which they are placed in
a torsion machine to investigate the torque during rotation.
The experiments result in similar rotations and torques as the
simulations. The designed Hygromorphic Rotational Actuator is
capable of passively rotating its own structure, thereby expanding
the possibilities of engineers and designers when designing passive
autonomous systems.