project specification

Dielectric Elastomer Actuator

A fin-like dielectric elastomer actuator (DEA) that drives a miniature autonomous underwater vehicle (AUV). The fin-like actuator is modular and independent of the body of the AUV. All electronics required to run the actuator are inside the 100 mm long 3D-printed body, allowing for autonomous mobility of the AUV. The modular DEA is capable of powering a miniature underwater vehicle. The soft actuator is integrated into a small and fully self-contained package that can be mounted on various AUVs. The DEA requires no pre-stretch of the elastomers, and is sealed for underwater usage. Only a minimal sealing is required since only four wires per actuator go into the vehicle’s body

Specifications

Heigh60 mm
Length100 mm
Width30 mm
Mass115 g
Speed8 mm/s
Fabrication method3D printing
Battery7.4 V,180 mAh
Costs300 $
Microcontroller1 Arduino Pro Mini

Overview

The fin-like actuator is modular and independent of the body of the AUV. All electronics required to run the actuator are inside the 100 mm long 3D-printed body, allowing for autonomous mobility of the AUV.

The modular DEA is capable of powering a miniature underwater vehicle. The soft actuator is integrated into a small and fully self-contained package that can be mounted on various AUVs. The DEA requires no pre-stretch of the elastomers, and is sealed for underwater usage. Only a minimal sealing is required since only four wires per actuator go into the vehicle’s body. 

Design

The bimorph actuators can flap and propel a swimming robot. Two similar unimorph actuators are connected by a double-sided adhesive to create a bimorph architecture. When one half of the bimorph is actuated, the second half and the adhesive serve as a non-stretchable constraint, directing the actuator to bend. 

Robot design

The 3D-printed body contains an Arduino Pro Mini microcontroller, an SD card reader/writer for data logging, a Li-Ion battery, and a power circuit to provide the high actuation voltage to the DEAs. A pressure sensor used for depth control, an LED for status indication, two waterproof Micro-B USBs for charging and programming, and an on/off switch penetrate the top end of the body;  a ground and  two positive supply voltage cables are routed to the DEA driven fin at the back.
The flapping motion of the fin is achieved by switching on and off the two halves of the bimorph DEA.

References

Describes the design guidelines for the fin-like DEA are detailed in The reconfigurable and miniature AUV is shown. Results including measurements of thrust and speed as well as planar swimming and vertical diving are discussed.

Florian Berlinger, Mihai Duduta, Hudson Gloria, et al.

Wevolver 2022