0
$\begingroup$

What is the meaning of power/energy density of an actuator?

Context: As a novel kind of actuator, the dielectric elastomer ( DE ) demonstrates high-strain response [ 1 ] , high energy densities ( seventy times higher than conventional electromagnetic actuators ) [ 2 ] , and high energy conversion ef fi ciencies ( 60% – 90% [ 3 ]) .

$\endgroup$
1
$\begingroup$

Power density is defined and understood as the average power over the weight and/or volume of the actuator (depending on the unit). Here, it is understood as the effective power output divided by weight (or volume)

For example, if your actuator is made from $2kg$ of DE and delivers $5W$ worth of power, then the power density is $5/2=2.5W/kg$

Thanks @Phil Sweet for this comment. I'd add an example for power density per unit volume.

Again, the DE actuator is $5W$ in output, and it has a volume of $0.02m^3$, the its power density will be $5/0.02=250W/m^3$

$\endgroup$
1
  • $\begingroup$ With any luck, it is only used for volume. Specific energy and specific power should be used for per-unit-mass terms. I don't get too worked up if this isn't the case, but please change the example to reflect the preferred usage. $\endgroup$
    – Phil Sweet
    Aug 21 '19 at 3:11

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.