Table 4: Quality comparison of actuators: adapted from [35, 79].

ActuatorsAdvantagesDisadvantages

Linear actuators

Piezoelectric Ceramic(i) Excellent performances except strain output(i) Require high activation voltage
(ii) Strain output can be magnified using bender arrangements

Shape memory alloy(i) Excellent performance except frequency range(i) Poor fatigue life

Magnetostrictor(i) Excellent performances except strain output(i) Require high activation voltage

Solenoid(i) High strain(i) Low energy density

Electroactive Polymers (EAP)(i) Dielectric elastomers outperform muscle in both stress and strain output.(i) Only ionic EAPs operate on low voltage
(ii) Novel technology not widely available

Rotary actuators

Electric motors(i) Efficiency(i) Weight
(ii) Reliability(ii) Dimensions
(iii) Versatility