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Project Notes

#604 Mini Linear Servos

Testing some mini/micro linear servo motors with an ATtiny85.



Most common servos are of the rotary kind. Linear servos are a little more rare and tend to be a bit more expensive but they do have some advantages, such as generally more compact design.

In this project note, I’ll be putting a few mini/micro linear servos through some basic tests.


Here’s the basic setup. By default I have the ATtiny85 flashed for 8MHz internal clock, and I’m using PB4 (pin 3 on the DIP8 ATTiny85) as the servo control pin.



Test Sketch

See MiniLinearServos.ino for the test sketch. It uses the SoftwareServo library. These servos can easily be used from as Arduino by switching to the standard Arduino Servo library.

1.5g Micro Linear Servo GS-1502

These GS-1502 servos were from a seller on, and come in a matched left/right handed pair.


Item Specifications
Weight 1.8g(include connector wire)
Speed 0.11 sec @3.7v
Torque 29.5g of force
Rotation maximum 180°
Voltage 3.7V-5V
Gear Nylon
Dimensions 21 x 15 x 12mm (LWH)
Tye digital.
Application Ultra Micro aircraft

This serve works very well. I had to adjust the minimum pulse width to 832µs with the command myServo.setMinimumPulse(832); to allow a full range potisioning from 0˚ to 180˚.

With the 540µs default setting, the servo would automatically return to “home” (180˚) whenever positioned below 27˚.

Here’s a quick demo..


Credits and References

Project Source on GitHub Project Gallery Return to the LEAP Catalog

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

LEAP is just my personal collection of projects. Two main themes have emerged in recent years, sometimes combined:

  • electronics - usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting
  • scale modelling - I caught the bug after deciding to build a Harrier during covid to demonstrate an electronic jet engine simulation. Let the fun begin..
To be honest, I haven't quite figured out if these two interests belong in the same GitHub repo or not. But for now - they are all here!

Projects are often inspired by things found wild on the net, or ideas from the many great electronics and scale modelling podcasts and YouTube channels. Feel free to borrow liberally, and if you spot any issues do let me know (or send a PR!). See the individual projects for credits where due.