Page 368 - Flexible Robotics in Medicine

360 Chapter 15
Table 15.4: Fracture strength and elongation at break of films.

Sample Fracture strength (MPa) Elongation at break (%)
IL/PVDF-HFP 20 wt.% IL 91.3 350.0
PEDOT:PSS/xylitol 26.9 25.3

Tests on the actuation of the IL/PVDF-HFP/PEDOT:PSS/xylitol was conducted. In the
previous attempts, a composite with a length of 2 cm and a width of 5 mm was used.
However, if the width is too small, the probe’s electrodes could quickly come into contact
with each other, which results in the possibility of a short circuit. However, this adjustment
may compromise the actuation of the composite films. Hence, the actuator dimensions and
the applied driving field strength also play essential roles that require more comprehensive
tests in the future.

15.4 Conclusion

We discussed the different properties of PEDOT:PSS/xylitol/Fe 3 O 4 magnetic actuator and
IL/PVDF-HFP/PEDOT:PSS/xylitol bending actuator. These soft actuators are flexible and
ductile, which makes them suitable for biomedical uses. However, aside from their
actuating functions, the biocompatibility of these actuators should also be improved to
ensure safety. Both forms of actuators have their advantages and disadvantages. In terms of
the type of field required to activate the actuators, magnetic actuators are more convenient
for untethered setup as compared to the EAP bending actuator for biomedical applications.
For example, the human body can withstand a magnetic field strength of 1.5 T during an
MRI scan [11]. However, concerns have been raised with regard to the toxicity of magnetic
Fe 3 O 4 NPs to the human body [12]. Hence, extra care must be given if the actuator needs to
function in vivo.

References

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