Micro linear actuators solve small-motion problems, not impossible-motion problems. They fit where normal actuators will not, but they still need proper force, stroke, alignment, brackets, and wiring. Small size makes side load and bad geometry less forgiving, not more forgiving.
"Micro actuators do not forgive what bigger actuators absorb. A small rod under side load bends; a small bracket under misalignment binds. Get the geometry right first, then size the force."
What are micro linear actuators?
Micro linear actuators are compact electric actuators built for short strokes, small spaces, and lighter loads. They turn motor rotation into straight-line motion in a small package.
What is the simple explanation?
Use a micro actuator when the space is small and the load is modest. Do not use one to rescue a bad hinge angle or overloaded mechanism.
Use the formula below for a first-pass force target.
Force target = working load × safety factor
What should the calculator inputs be?
Use this as a first-pass sizing tool. Then confirm the final choice against the actual FIRGELLI product page, the wiring diagram, and your real mounting geometry.
How do you use this calculator?
- Enter the real project values, not guesses from a different mechanism.
- Use measured current, load, stroke, voltage, or signal values where you can.
- Add margin for real brackets, wiring, friction, and installation conditions.
- Click Calculate to see your result.
How should you choose a micro actuator?
Start with stroke and packaging. If the actuator cannot physically fit at full retract and full extend, force does not matter.
Then check force, speed, duty cycle, feedback, brackets, and side load. The smaller the actuator, the more a bad bracket can ruin it.
What is a simple example?
A vent flap needs 2 inches of travel and sees about 8 lbs of working load. With a 1.5 safety factor, force target = 8 × 1.5 = 12 lbs.
Now check the actuator’s closed length, mounting points, speed, and whether the flap needs feedback or only end-to-end motion.
Recommended FIRGELLI setup
Which FIRGELLI products fit this job?
For micro projects, product fit starts with physical envelope and mounting, then force.
F12 Micro Linear Actuator
Use this when the project needs very small linear motion and the force/stroke options fit the mechanism.
View F12 Micro Actuators
Micro Pen Actuator with Feedback
Use this when a compact actuator also needs built-in feedback for position-aware control.
View Micro Pen with Feedback
Mini Linear Actuator
Use this when the job is still compact but needs more conventional mini actuator packaging.
View Mini Linear ActuatorsUse MB24 brackets where they fit the selected actuator, and check the linear actuators collection for larger options.
What are common mistakes when using this calculator?
- Entering working load instead of peak load. The actuator has to handle the worst-case force, not the average. Use the highest expected load before applying the safety factor.
- Ignoring closed length. A force-correct actuator that will not retract into the available space is still the wrong actuator. Always check the closed dimension against your installed envelope.
- Forgetting side load. The calculator sizes for axial force. If the mechanism puts the rod in bending, the real load on the actuator is higher than the calculator shows.
- Skipping the safety factor. Friction, voltage sag, and aging seals all reduce real-world force. 1.5× is a starting point, not a maximum.
- Using catalog stroke as required stroke. Required stroke is what your mechanism needs at the pin centers, not the actuator's full travel. Measure the mechanism first.
How can you verify the calculator output is reasonable?
- Cross-check against the product page. The calculator gives a force target. Confirm the chosen actuator's rated force, stroke, and closed length on the actual FIRGELLI product page before ordering.
- Dry-run the mechanism by hand. With the actuator removed, move the mechanism through its full travel and feel for binding, friction, or unexpected resistance. If it feels hard by hand, the calculated force is too low.
- Compare with a known similar build. If a similar mechanism in another project used a specific actuator at a known load, the new calculation should land in the same range. Large deviations usually mean a wrong input.
- Sanity-check the safety factor. For a clean, well-guided mechanism, 1.5× is reasonable. For a flap fighting wind or a load with shock, raise the safety factor and recheck.
- Verify on real load, not bench. Bench tests with no load prove the actuator runs. Only loaded cycle testing confirms the sizing.
Where are micro linear actuators used?
Micro actuators fit jobs where space is the binding constraint, not force. Typical applications include:
- Smart furniture and home office: small drawer releases, hidden panel flips, monitor tilt mechanisms.
- Robotics: compact joints, grippers, end-effector adjustments where servo torque alone is not enough.
- RV and marine vents: small flap, louver, and damper actuation where larger actuators do not fit.
- Medical and lab equipment: small linear motion inside enclosed devices, where stroke is short and load is light.
- Model and display work: retail displays, animatronics, and demonstration rigs needing short, repeatable strokes.
In each case, the deciding factor is the closed-length envelope first, then force and stroke.
