Automation 101: The Start of Your Project

Planning Your First Linear Actuator Project: A Complete Engineering Guide

Every successful automation project starts with a simple engineering question: what motion must happen, under what load, and how will it be controlled? Whether you are building a custom TV lift, automating a sliding cabinet, opening a hinged hatch, or moving a panel in an RV or marine application, the process is much easier when you work from requirements instead of starting with a product page.

FIRGELLI Automations has helped DIY builders, fabricators, and professional engineers design linear motion systems since 2002. The most common early-stage mistake is selecting a linear actuator before the load, stroke, mounting geometry, voltage, and control method are understood. An actuator can provide reliable push-pull force, but it cannot compensate for a binding hinge, a weak bracket, an undersized power supply, or a stroke length that was guessed instead of measured.

This guide uses a practical workflow: define the mechanism, measure the required travel, estimate force, choose the actuator, then select the brackets, power supply, switches, controllers, and wiring around that actuator. The examples below use round-number assumptions for clarity. Your final design should always be checked against the specifications for the exact actuator, bracket, controller, and power supply you plan to use.

A good first pass can be summarized as five questions:

• What object is moving, and does it already move smoothly by hand or by fixture?
• How far does it need to move from fully closed to fully open?
• How much force is required at the worst point in the travel?
• How fast should the motion occur, and is that speed realistic for the force required?
• How will the actuator be powered, controlled, mounted, and tested safely?

If you answer those questions before ordering parts, you will avoid most of the problems that cause automation projects to stall: short stroke, insufficient force, incompatible brackets, excessive voltage drop, and control systems that cannot handle motor start-up current.

Step One: Define the Motion Requirements

The best automation projects begin with a mechanism that already works mechanically. The actuator should replace or assist manual effort; it should not be used as a cure for poor alignment. If you are automating a hinged lid, the lid should swing freely on its hinge before the actuator is installed. If you are motorizing a sliding shelf, the shelf should travel smoothly on rails. If a drawer jams when pushed by hand, an actuator will usually make the problem worse by forcing the jam repeatedly into the same point.

Start by identifying the motion category. Linear vertical motion is the easiest to visualize because the actuator is lifting against gravity. Horizontal sliding motion usually depends more on friction than on total object weight. Hinged motion is more complex because the actuator is applying a linear force to create rotary motion about a hinge. The required actuator force changes throughout the arc because the lever arm and actuator angle are changing.

Also define what “success” means for the end user. A hidden TV lift may need to move quietly and stop cleanly at a precise height. A service hatch may need strong holding force and weather resistance. A cabinet door may only need a short, smooth opening movement. Those requirements influence whether you choose a simple rocker switch, a remote, a feedback actuator, or a synchronized multi-actuator control system.

Practical Checks Before You Calculate Anything

• Move the mechanism manually. It should complete the full travel without binding, twisting, or rubbing.
• Check both end positions. The closed and open positions must leave room for the actuator body, rod, brackets, wiring, and any pivoting movement.
• Identify the worst load condition. A lid may require the most force just after it starts opening, while a vertical lift may see the same gravitational load throughout travel plus friction.
• Look for side loading. Linear actuators are designed for axial push-pull loads. Use rails, hinges, slides, or guides to support side loads rather than forcing the actuator rod to act as a structural guide.
• Plan for service access. Mount the actuator where brackets, pins, and wiring can be inspected and replaced later.

Common Motion Types and Design Considerations

The table below compares typical first projects. It is not a substitute for project-specific calculations, but it gives you a useful starting point for what to measure and what mistakes to avoid.

Motion type	Primary load to overcome	Key measurements	Useful design checks	Common mistake
Vertical lift	Full lifted weight plus slide or guide friction	Total travel, moving weight, guide spacing, available actuator length	Verify guides carry side load; add a safety margin above calculated load	Ignoring the weight of the platform, brackets, and moving hardware
Horizontal slide	Static friction, rolling resistance, seals, and cable drag	Travel distance, friction force, rail alignment, cable path	Measure push force with a scale if possible; check for binding at both ends	Choosing actuator force from object weight instead of measured sliding resistance
Hinged lid or hatch	Torque from lid weight around the hinge, plus gas struts or seals if present	Hinge location, lid center of gravity, desired angle, fixed and moving bracket positions	Model closed and open triangles; check force at the worst angle	Assuming stroke equals lid opening distance rather than bracket-to-bracket distance change
Multi-actuator lift	Shared load plus unequal friction between corners or guides	Total moving weight, actuator spacing, guide stiffness, synchronization requirement	Use feedback actuators and a synchronization controller when positions must match	Powering multiple non-feedback actuators together and expecting perfect alignment
Small enclosure or display motion	Light force, limited space, and packaging constraints	Stroke, retracted length, bracket clearance, wire routing	Confirm the actuator body fits in both end positions	Selecting a force rating that fits but overlooking the actuator’s physical length

Step Two: Quantify the Motion and Calculate Stroke Length

Once the mechanism is defined, document it. A simple scale drawing is often enough for a first project. Mark fixed pivots, moving pivots, fully closed position, fully open position, available mounting space, and any obstacles. If the project is important or geometry is tight, model it in CAD or build a cardboard or plywood mock-up before drilling final holes.

For a straight sliding or lifting application, stroke length is the distance the load must travel. If a panel must move 20 inches to clear an opening, the actuator needs at least 20 inches of stroke. In practice, leave adjustment room. A slightly longer stroke can often be limited by external limit switches, controller settings, or mechanical stops, but a short actuator cannot extend beyond its manufactured stroke. Do not rely on “close enough” when clearance is tight.

For vertical lifts, include the full useful travel, not just the visible travel. For example, a cabinet TV lift may need the screen to rise 30 inches above the cabinet top, but the carriage, brackets, and initial hidden position may require additional actuator travel depending on the lift design. If you are designing a lift rather than buying a complete TV lift, draw the full linkage and confirm that the actuator can retract far enough for the closed position and extend far enough for the viewing position.

Calculating Stroke for Hinged Applications

Hinged applications require more care because a rotary motion is being driven by a linear actuator. The actuator stroke is not the length of the lid, and it is not the vertical height of the opening. Stroke is the difference between the actuator pin-to-pin distance in the closed position and the actuator pin-to-pin distance in the open position.

For a hinged lid, define these points:

• The hinge axis.
• The fixed actuator bracket location on the base or frame.
• The moving actuator bracket location on the lid or hatch.
• The desired final opening angle.
• The lid weight and approximate center of gravity.

Draw the closed triangle and the open triangle. Measure or calculate the distance between the actuator mounting pins in both positions. The difference is the required stroke. Then check force. The actuator may have enough stroke but still lack the force needed at the start of motion, where many hinged lids have the least favorable mechanical advantage.

For common hinged layouts, the Actuator Stroke Length Interactive Calculator for hinged applications can reduce trial and error. If your geometry includes an incline, significant friction, or a non-standard angle, the Linear Motion Calculator can also help frame the relationship between load, force, and travel. Treat calculator output as a design aid, then confirm the result against the physical product drawings and your actual mounting constraints.

Example: Sliding Cabinet Panel

Assume a sliding panel needs to travel 18 inches to uncover an appliance bay. The panel weighs 35 lb, but it rides on ball-bearing slides. A pull scale shows that it takes about 8 lb of force to start moving and 5 lb to keep moving. In this case, the actuator is not lifting 35 lb vertically; it is overcoming sliding resistance. A designer might choose an actuator with more than 8 lb of available force and an 18-inch or longer stroke, then add a safety margin for dust, misalignment, and aging of the slides. The final choice would also depend on speed, retracted length, and mounting clearance.

Step Three: Select Actuators Based on Force and Speed Specifications

With stroke and force requirements in hand, you can begin selecting an actuator. Start with non-negotiable requirements: voltage, stroke, force, environmental needs, physical envelope, and whether position feedback is required. Then evaluate speed and control options. This order matters because speed preferences do not help if the actuator cannot fit, cannot lift the load, or cannot survive the environment.

Force ratings describe the maximum push or pull load an actuator is intended to handle under specified conditions. FIRGELLI actuator families range from compact micro linear actuators for small mechanisms to industrial actuators for high-force applications. Do not size right at the calculated load. A 20 to 30 percent reserve is a common planning margin for many projects, and more margin may be appropriate when friction, shock loading, outdoor exposure, or user abuse is likely.

Understanding the Speed-Force Relationship

Linear actuator speed and force are linked through the motor and gearing. In general, higher force requires greater gear reduction, and greater gear reduction reduces output speed. That is why a high-force actuator is usually slower than a low-force actuator with a similar motor technology. If your project needs both high speed and high force, confirm that the combination is physically realistic before designing the rest of the machine around it.

As an example assumption, a light-duty display panel may tolerate a fast actuator because the force is low. A heavy hatch may require a slower, higher-force actuator. If the opening time is important, calculate it early. The Free Actuator Speed Calculator can help estimate extension time from stroke and speed, while the Linear Actuator Speed vs. Force Tradeoff Calculator is useful when you are comparing design compromises.

Force Sizing Notes Builders Often Miss

• Static friction is higher than running friction. A mechanism that moves easily once started may still need a larger actuator to break free from rest.
• Seals can dominate the load. Weather stripping on a hatch or cabinet can add more resistance than the panel weight suggests.
• Gas springs change the force curve. They may help lifting in one portion of travel but resist closing in another.
• Mounting angle changes usable force. In hinged applications, the actuator’s rated force is along its rod; only part of that force becomes useful torque at the hinge.
• Shock and impact are different from steady load. If users slam the mechanism, add mechanical stops and design the structure to absorb impact rather than relying on the actuator gearbox.

Plan the Control System Before You Drill Mounting Holes

A single actuator controlled by a manual rocker switch is straightforward. The switch reverses polarity to extend or retract the actuator. A remote system adds convenience. A feedback actuator adds position information. A synchronized system uses position feedback to keep multiple actuators moving together. Each step adds capability, but also adds wiring, setup, and troubleshooting.

Ask these questions before committing to a control architecture:

• Will one actuator move the entire mechanism, or are multiple actuators required?
• If multiple actuators are used, do they need to stay synchronized?
• Does the system need preset positions, soft stops, or programmable behavior?
• Will the user control the motion locally, wirelessly, or through another controller?
• Does the installation need position feedback for safety, repeatability, or diagnostics?

If actuators must move together, use feedback actuators and a compatible synchronization controller. If you need custom logic, an Arduino or PLC-style controller may be appropriate, provided the motor power is switched through correctly rated relays or motor drivers.

Step Four: Build the Rest of the System Around Actuator Requirements

After the actuator is selected, specify the surrounding system. This includes mounting brackets, pins, linkages, power supply, switches, controllers, wiring, fuses, and mechanical stops. Selecting these parts after the actuator prevents compatibility problems. For example, a controller that works with a small actuator may not be rated for a larger actuator’s current draw.

Mounting Brackets and Mechanical Hardware

Most rod-style actuators use clevis-style end mounts that allow the actuator to pivot as the mechanism moves. That pivoting is essential in hinged applications because the angle between the actuator and the lid changes throughout travel. Use brackets designed for the actuator family and confirm that the bracket pin size, hole pattern, and load path match the application.

Brackets should be mounted to structure, not just thin cosmetic panels. A bracket that is strong enough in isolation can still fail if it is bolted to weak material. Use backing plates, gussets, or welded structure where loads are high. Also check that the actuator rod is not forced into side load at either end of travel. Misalignment can cause noisy operation, premature wear, or bent hardware.

Electrical Power Requirements and In-Rush Current

DC motors draw a brief start-up surge called in-rush current. This surge can be much higher than the current drawn while the actuator is moving steadily under a light load. Your power supply, switch, relay, controller, and wiring must tolerate the peak demand, not just the average running current. If the power supply is undersized, the actuator may hesitate, reset the controller, or fail to start under load.

Current also increases with load. An actuator moving freely on the bench may draw far less current than the same actuator lifting a real mechanism. That is why bench testing should be followed by loaded testing before the project is enclosed. If exact current values are not known during early planning, use the product specifications for the actuator and size the electrical system conservatively.

For energy-sensitive projects such as battery-powered equipment, the Linear Motion Energy Consumption calculator and the Actuator Power Consumption Calculator can help estimate power and runtime using stated assumptions.

Voltage Considerations: 12V vs. 24V Systems

Many hobby, automotive, RV, and residential low-voltage projects use 12V DC because batteries, switches, and accessories are widely available. Industrial and longer-run systems often use 24V DC because the same power can be delivered with lower current, reducing voltage drop and heat in the wiring. Neither voltage is automatically better; the correct choice depends on the actuator model, controller compatibility, wire length, and the power source already available.

Choose one voltage standard for the actuator system whenever possible. Mixing 12V and 24V devices in the same control layout requires careful isolation and separate power conversion. Before ordering, verify the voltage rating of every actuator, controller, relay, remote receiver, and power supply in the system.

Mechanical Stops, Limit Switches, and End-of-Travel Protection

Many actuators include internal limit switches that stop travel at the built-in fully extended and fully retracted positions. Your mechanism may need to stop before those points. In that case, use appropriate external limit switches, controller settings, or mechanical design features so the actuator does not drive the structure into a hard jam. Mechanical stops should be placed so they protect the machine, not so the actuator repeatedly stalls against them under power.

During design review, confirm what happens if a user holds the switch too long, if a remote button is pressed accidentally, or if an obstruction enters the path. A simple project may only need careful placement and end stops. A more complex project may require current sensing, position feedback, guarding, or interlocks.

Step Five: Order Components and Understand Warranty Coverage

Before ordering, make a bill of materials and review it as a system. Include the actuator, brackets for both ends, power supply, control method, wire, connectors, fuses, mounting hardware, and any sensors or limit switches. Check product drawings for retracted length, extended length, mounting dimensions, and the clearance required for the actuator to pivot.

FIRGELLI actuators include warranty coverage for manufacturer defects under the stated warranty terms for the product. Warranty coverage does not replace proper sizing and installation. Damage caused by misuse, overload, incorrect voltage, water exposure beyond the product rating, wiring errors, or operation outside the published specifications is not the same as a manufacturing defect. If a project is experimental or the load case is uncertain, build in extra margin and test carefully before final installation.

Returns are easiest to avoid through measurement discipline. Before placing an order, confirm these items:

• Required stroke and available mounting length.
• Force requirement with a suitable safety margin.
• Voltage compatibility across every electrical component.
• Controller current rating compared with actuator maximum current.
• Bracket compatibility with the selected actuator.
• Wire run length and planned wire gauge.
• Environmental exposure such as dust, moisture, temperature, or vibration.

Step Six: Wiring, Testing, and Installation

When the parts arrive, do not install them permanently first. Build the system on a bench and confirm that the actuator extends and retracts correctly, the switch or controller reverses direction as expected, and the power supply remains stable during start-up. A bench test isolates electrical issues before the actuator is hidden inside a cabinet, hatch, or frame.

Use Wiring Diagrams and Label the System

Each component should be wired according to its own instructions. Keep polarity clear, label conductors, and protect connections from vibration. For a simple rocker switch system, the wiring may be only a power supply, switch, and actuator. For feedback or synchronized systems, wiring errors can be harder to diagnose, so label motor leads, feedback leads, power leads, and control inputs separately.

Wire Sizing and Voltage Drop

Actuators often include short leads suitable for testing, but real installations may require longer runs. Wire gauge depends on current and distance. Longer wires and higher current create more voltage drop, which reduces actuator performance. In a 12V system, even a small voltage loss can be noticeable because the system voltage is low to begin with.

Use the actuator’s maximum current specification, the total circuit length, and the system voltage to select wire gauge. The total circuit length includes both the positive and negative path. If a calculator recommends a gauge close to the limit, choose the heavier wire. Slightly oversized wire is usually cheaper than troubleshooting a voltage drop problem after the project is assembled.

Example Wiring Configurations

The simplest actuator system uses a DC power supply, a reversing rocker switch, and one actuator. This is suitable for manual open-close control where the user can see the mechanism and stop it as needed.

A more complex system may use multiple switches, relays, and a controller such as an Arduino. The controller should not be expected to power the actuator directly; it should command properly rated relays or motor drivers. If position logic is required, use an actuator with the correct feedback type and a controller designed to read it.

Most real-world projects fall between those two examples. A remote control can add convenience while keeping the system simple. A control box can handle relay logic or synchronized movement without requiring custom code. Choose the simplest control system that satisfies the requirements, because simple systems are easier to install, explain, and troubleshoot.

Final Installation Checklist

• Cycle the mechanism by hand before connecting the actuator.
• Install brackets squarely and tighten hardware with appropriate locking methods.
• Support the load with guides, hinges, or rails so the actuator only sees axial force.
• Route wires away from pinch points, sharp edges, and moving linkages.
• Test unloaded, then test under partial load, then test under full load.
• Listen for changes in sound that indicate binding or overload.
• Confirm the actuator stops before the structure reaches a damaging position.
• Recheck fasteners after the first few cycles and again after initial use.

Conclusion: From Planning to Successful Installation

A reliable automation project is not the result of guessing the largest actuator that will fit. It comes from defining the motion, measuring the geometry, calculating or testing the force requirement, selecting compatible components, and validating the system before final installation. The actuator is the heart of the system, but the brackets, structure, wiring, power supply, and controls determine whether it performs reliably in the real application.

For first-time builders, the most valuable habit is to document assumptions. If you assume a 40 lb lid, write that down. If you estimate 10 lb of sliding friction, measure it later with a scale. If you choose a 20 percent safety margin, confirm that the selected actuator still fits and moves at an acceptable speed. Engineering does not require perfect information at the start, but it does require that assumptions be visible and checked before the design is finalized.

FIRGELLI provides product specifications, wiring resources, calculators, and application examples to help you move from idea to working system. Use them early in the process, and your first automation project will be far more likely to work the way you intended.

Frequently Asked Questions

How much weight can a linear actuator lift?

It depends on the actuator’s force rating, mounting geometry, and the load direction. In a vertical lift, the actuator must overcome the moving weight plus friction. In a hinged lid, the actuator must overcome hinge torque, and the required force changes with angle. Always compare your calculated worst-case force with the specific actuator rating and include a safety margin.

What stroke length do I need?

For straight-line motion, stroke is the required travel distance. For hinged motion, stroke is the change in actuator pin-to-pin distance between the closed and open positions. Draw both positions and measure the mounting distance in each. If you are unsure, use a hinged actuator calculator or mock up the geometry before drilling permanent bracket holes.

Can I use a longer stroke actuator and stop it early?

Often yes, provided the actuator physically fits in both retracted and extended positions and the control system stops motion at the correct points. A longer stroke can offer mounting flexibility, but it must not be allowed to overdrive the mechanism into a hard stop. Use appropriate limit switches, controller settings, or mechanical design safeguards.

Can I use multiple actuators together?

Yes, but the control method matters. Independent actuators can be wired with separate controls if they do not need to stay aligned. If two or more actuators lift the same platform or must maintain position together, use feedback actuators and a synchronization controller. Standard non-feedback actuators may drift apart because small differences in load and speed accumulate over travel.

Why does in-rush current matter?

In-rush current is the short current surge that occurs when the actuator motor starts. A power supply or controller that is only sized for light running current may trip, reset, or fail to start the actuator under load. Size electrical components for the actuator’s specified current requirements and leave margin for real-world loading.

Should I choose 12V or 24V?

Choose the voltage that matches your actuator, controls, and power source. Many vehicle and DIY projects use 12V. Longer wire runs and industrial systems often benefit from 24V because current is lower for the same power. Do not mix voltages casually; verify every component before ordering.

What mounting brackets do I need?

Bracket choice depends on the actuator family and the load path. Most applications use clevis brackets that allow pivoting at each actuator end. Confirm compatibility with the actuator model, mount the brackets to strong structure, and avoid side loading the actuator rod. If the actuator cannot pivot naturally through the full motion, revise the bracket geometry before powered testing.

How do I avoid common first-project mistakes?

Measure the mechanism, do not guess. Check stroke in the real geometry, not just in a sketch. Choose force with margin. Select the actuator before the power supply and controller. Bench test the wiring before installation. Finally, cycle the mechanism under load while watching and listening for binding before you enclose it or hand it over to the end user.