ServoCylMotion engineering and motion-system evaluation environment
Engineering resource / preliminary requirement model

Linear Actuator Sizing Calculator

Estimate preliminary force, stroke and installed-length requirements before product matching. Keep the assumptions visible, then verify the result against current product data, geometry and operating conditions.

/ 01 / Calculate the requirement

Model the mechanism first. Then size the actuator.

This calculator is an early engineering aid. It does not verify model-specific load-speed performance, duty, side load, structural strength, controls or safety conditions.

01 / Motion + geometry inputs Unknown values should remain explicit
Horizontal model: gravity is not added along the travel direction. Enter measured guide resistance where possible.
/ 02 / Calculation logic

Keep gravity, resistance, acceleration and leverage visible.

Hiding all force components inside one result makes review harder. A useful sizing record shows where the requirement came from and where assumptions remain.

Direct motion F = Fg + Fr + Fa + Fexternal

Gravity depends on travel direction, guide resistance should be measured where practical, and acceleration matters when the load must reach speed quickly.

For horizontal travel, gravity does not directly oppose ideal aligned motion. For incline and vertical travel, it can dominate the requirement.
Hinged / pivoting motion Factuator = Mresisting / r⊥

The actuator must generate enough moment around the pivot. As the perpendicular moment arm becomes smaller, actuator force can rise sharply.

The interactive hinged estimate uses the entered effective line angle as a simplified worst-case lever-arm model. Validate the real geometry through the full motion range.
ServoCylMotion engineering measurement and verification context
/ 03 / Geometry before oversizing

A small mounting change can create a large force change.

For lids, hatches, doors and levers, evaluate leverage across the motion rather than only at one convenient angle. If the line of action passes close to the hinge, the effective moment arm shrinks and required force rises.

01 Define the hinge, center of gravity, moving actuator mount and fixed mount unambiguously.
02 Evaluate the worst position through the intended opening range, not only the start or end position.
03 If force spikes, improve geometry before simply choosing a much larger actuator.
04 Check both retracted and extended pin-to-pin dimensions before product release.
/ 04 / Input checklist

Measure the motion, not just the payload.

For existing mechanisms, measured guide resistance and real mounting geometry are more useful than generic assumptions.

Input What to enter Why it matters
Moving load Total payload plus moving structure Sets the gravity and inertial basis
Direction / angle Horizontal, incline, vertical or hinged geometry Changes gravity and leverage
Guide resistance Measured resistance where available Captures real friction and mechanism losses
Loaded speed Required motion speed under load Used for product matching and travel time
Travel / geometry Linear travel or open/closed mount lengths Defines preliminary stroke and installed fit
Actuator count Units expected to share the work Only a preliminary load-sharing assumption
Engineering margin Project-specific multiplier Keeps uncertainty visible instead of hidden
/ 05 / Multi-actuator systems

Dividing force by two does not prove equal load sharing.

Uneven center of gravity, frame stiffness, mounting tolerances, racking and timing differences can place more load on one actuator. Treat the per-actuator value as a preliminary starting point only when geometry is symmetric and load sharing is credible.

A Review frame stiffness and load offset.
B Review synchronized or coordinated control where timing matters.
C Validate the real assembly rather than assuming perfect sharing.
Representative ServoCylMotion linear actuator for sizing context
/ 06 / What the calculator does not verify

The output is a requirement—not a model approval.

Before selecting or releasing a design, verify the candidate at configuration level.

Verify next What to check
Performance Force at required loaded speed, stroke options, static/dynamic definitions, duty and thermal limits
Geometry Retracted/extended dimensions, side load, alignment, brackets, hinges, frame strength, clearance and end stops
Gravity safety Braking or holding behavior where a gravity-loaded mechanism could back-drive or fall
Environment Temperature, corrosion, contamination and ingress requirements
Electrical system Supply voltage/current, feedback, limits, controller and synchronization
/ 07 / Calculation to candidate

Carry the requirement forward without losing the assumptions.

The sizing output becomes more useful when it moves into product matching, dimensional verification and system review as one traceable requirement set.

01 Calculate Force, stroke, fit, speed and assumptions.
02 Narrow Use the Product Selector to screen families.
03 Compare Review available linear actuator families.
04 Verify fit Check CAD, dimensions and current data.
05 Verify system Power, controls, feedback and environment.
06 Resolve Escalate uncertain geometry or safety conditions.
/ 08 / FAQ

Use the result as an engineering input.

Keep uncertainty visible and verify the real mechanism before release.

What should I measure before using the calculator?

Start with motion type, total moving load, required travel, target loaded speed and actuator count. Add travel angle and resistance for direct motion; add hinge, center-of-gravity and actuator mounting geometry for pivoting mechanisms.

Why can a hinged application need more actuator force than the load weight?

The actuator creates torque through a lever arm. When its line of action passes close to the hinge, the perpendicular moment arm becomes small and required actuator force rises.

Is actuator stroke always equal to load travel?

No. That approximation applies only to aligned direct motion. Hinges, levers, angled mounts and other linkages convert actuator travel into a different load path.

How should I choose the engineering margin?

Use a factor that reflects uncertainty in load, friction, impact, wear, geometry and operating conditions. Keep the factor visible in the record; it does not replace structural or safety analysis.

Can I divide the force equally between two actuators?

Only as a preliminary assumption when geometry is symmetric, the structure is sufficiently stiff and the actuators remain coordinated. Validate actual load sharing.

Engineering review / unresolved sizing risk

Send the requirement set when geometry or operating conditions remain uncertain.

Include the mechanism sketch, load, target speed, required travel, mounting geometry, duty, environment and calculated assumptions.

Request engineering review →