33,772 research outputs found
3D Printed Soft Robotic Hand
Soft robotics is an emerging industry, largely dominated by companies which hand mold their actuators. Our team set out to design an entirely 3D printed soft robotic hand, powered by a pneumatic control system which will prove both the capabilities of soft robots and those of 3D printing. Through research, computer aided design, finite element analysis, and experimental testing, a functioning actuator was created capable of a deflection of 2.17” at a maximum pressure input of 15 psi. The single actuator was expanded into a 4 finger gripper and the design was printed and assembled. The created prototype was ultimately able to lift both a 100-gram apple and a 4-gram pill, proving its functionality in two prominent industries: pharmaceutical and food packing
The role of electrostriction on the stability of dielectric elastomer actuators
In the field of soft dielectric elastomers, the notion electrostriction
indicates the dependency of the permittivity on strain. The present paper is
aimed at investigating the effects of electrostriction onto the stability
behaviour of homogeneous electrically activated dielectric elastomer actuators.
In particular, three objectives are pursued and achieved: i) the description of
the phenomenon within the general nonlinear theory of electroelasticity; ii)
the application of the recently proposed theory of bifurcation for
electroelastic bodies in order to determine its role on the onset of
electromechanical and diffuse-mode instabilities in prestressed or prestretched
dielectric layers; iii) the analysis of band-localization instability in
homogeneous dielectric elastomers. Results for a typical soft acrylic elastomer
show that electrostriction is responsible for an enhancement towards
diffuse-mode instability, while it represents a crucial property - necessarily
to be taken into account - in order to provide a solution to the problem of
electromechanical band-localization, that can be interpreted as a possible
reason of electric breakdown. A comparison between the buckling stresses of a
mechanical compressed slab and the electrically activated counterpart concludes
the paper
Performance of soft dielectric laminated composites
This paper contains a thorough investigation of the performance of
electrically activated layered soft dielectric composite actuators under plane
deformation. Noting that the activation can be induced controlling either the
voltage or the surface charge, the overall behaviour of the system is obtained
via homogenization at large strains taking either the macroscopic electric
field or the macroscopic electric displacement field as independent electrical
variable. The performance of a two-phase composite actuator compared to that of
the homogeneous case is highlighted for few boundary-value problems and for
different values of stiffness and permittivity ratios between constituents
being significant for applications, where the soft matrix is reinforced by a
relatively small volume fraction of a stiff and high-permittivity phase. For
charge-controlled devices, it is shown that some composite layouts admit, on
one hand, the occurrence of pull-in/snap-through instabilities that can be
exploited to design release-actuated systems, on the other, the possibility of
thickening at increasing surface charge density
- …