Linear Servos for Retractable Drone Landing Gear
When selecting actuation for retractable landing gear, engineers evaluate force capability, mechanical alignment, electrical integration, and overall system reliability. The actuator must extend and retract the mechanism predictably and tolerate landing loads without unnecessary linkage complexity. Linear servos provide direct push pull motion along the same axis as the required travel and can be commanded to a defined position using a standard RC servo PWM signal.
Force Capability
Actuonix linear servos cover a wide force range. Models such as the P16 deliver forces up to 300 N. This supports retractable landing gear on medium to large UAV platforms carrying commercial payloads and higher capacity battery systems.
Because force is defined directly, engineers can size structural members and guides based on known actuator output rather than calculating effective linear force from torque and lever geometry. For applications where direct linear force is preferred over rotational torque conversion, this simplifies load modeling.
Position Control
Actuonix linear servos are mechanically equivalent to linear actuators but include integrated control electronics that allow them to be commanded to a specific position using a standard servo signal.
- Repeatable extension and retraction endpoints
- Electronic definition of stroke limits
- Direct compatibility with RC receivers and flight controllers
All current Actuonix models are available in linear servo configurations.
Control Configurations
Most UAV landing gear systems use standard PWM servo control.
- -R series linear servos are plug and play compatible with standard RC receivers
- They can also be driven directly from embedded controllers that output servo PWM, though you must confirm that the board is capable of handling the load
For platforms with centralized or industrial control architectures, additional options within the product family include:
- I series models with onboard electronics supporting RC servo, 0 to 5 V, 4 to 20 mA, or PWM inputs
- P series models used with an external control board allowing adjustment of stroke limits and speed
- S series models operating through polarity reversal for basic extend and retract control
Servo controlled models are typically the most direct fit for retractable landing gear, while voltage or current based control may suit certain commercial UAV systems.
Stroke Range
Landing gear travel requirements vary by aircraft geometry. Actuonix rod style linear servos are available with stroke lengths from 10 mm up to 200 mm. This allows engineers to match servo stroke to required mechanical travel without adding secondary linkage to compensate for stroke mismatch.
Example Implementation
A common configuration uses a folding landing leg driven directly by a single linear servo aligned with the direction of motion. The servo extends to deploy the leg and retracts to stow it. A hinge or guided mechanism manages rotation and structural load transfer. Endpoints are defined electronically through the control signal. Structural members absorb landing loads. The linear servo provides controlled motion between defined positions.
Example Setups
- Direct Push Rod Retraction: Mount the linear servo inline with the landing leg’s primary direction of travel. The servo drives the leg through a hinge or guided pivot. Stroke endpoints are defined electronically via the RC servo PWM signal. Structural members absorb landing loads while the servo controls motion between defined positions.
- Folding Leg With Guided Linkage: Position the linear servo inside the fuselage and connect it to a short linkage that folds the leg inward. The servo provides direct linear force while the hinge geometry defines the stowed and deployed positions. This setup keeps the servo protected and simplifies alignment.
- Dual Leg Synchronized Deployment: Use two matched linear servos, one per leg, driven from the same control signal. This maintains symmetrical deployment without mechanical cross linking. Suitable for multirotor platforms with folding legs or fixed wing aircraft using dual main gear.
Image credit: Servo Magazine
These example setups illustrate practical ways to integrate linear servos into retractable landing gear mechanisms across airplane style and copter style UAV platforms.
Common Questions About Retractable Drone Landing Gear
What is the simplest control method for a retractable landing gear linear servo?
Most systems use a standard RC servo PWM signal. Actuonix -R series linear servos are plug and play compatible with common RC receivers and can also be driven by flight controllers or embedded systems that output servo PWM. If you're using a 12V -R series, you will need a 12V power source.
How much force do I need for retractable landing gear?
This is a calculation you must make as it depends on several variables including aircraft mass, landing gear geometry, and how the mechanism transfers loads. Actuonix linear servos cover a wide force range, with models such as the P16 delivering forces up to 300 N.
What stroke lengths are available for landing gear mechanisms?
Actuonix rod style linear servos are available with stroke lengths from 10 mm up to 200 mm, allowing engineers to match servo travel to the required landing gear motion.
Do you support OEM programs and custom specifications?
Yes. Actuonix offers dozens of linear servo configurations, and custom linear servo options can be developed for OEM programs meeting minimum volume requirements. Actuonix also offers a 50 percent development discount for customers evaluating linear servos in new applications.
Evaluate Linear Servos for Your Drone Landing Gear
Actuonix Motion Devices offers hundreds of linear servo configurations across different force ratings, stroke lengths, and control types. For OEM programs meeting minimum volume requirements, custom linear servo configurations can be developed to match specific force, stroke, or integration constraints. Actuonix offers a 50 percent development discount for customers evaluating linear servos in new applications. Contact us to discuss your landing gear requirements or request evaluation units.
