Servo Card Planning Guide 

Table of contents
  1. Servo Card Planning Guide
    1. Introduction
    2. Planning Context
    3. Uses
    4. References

Introduction

Servo motors on a model railroad layout provide controlled, repeatable mechanical movement, enabling realistic animation and precise positioning of layout elements.

In the LCC Fusion Project, servo-driven devices are implemented using the Servo Card, which generates controlled PWM signals in response to LCC events. These events originate from buttons, sensors, logic rules, or automation sequences elsewhere in the system.

Servos define how something moves; logic, signaling, and automation define when and why it moves. The Servo Card executes movement commands only and never encodes behavior.

Category Servo Use Description
Turnouts Turnout control Use servos to control turnouts (switches), enabling smooth and reliable route changes.
Signaling Signal operation Operate semaphore or mechanically driven signal aspects using servos.
Signaling Level crossing gates Open and close crossing gates in coordination with train movement.
Operations Coupler operation Automate coupling and uncoupling of rolling stock.
Operations Transfer tables Move transfer tables to align tracks in engine or service facilities.
Operations Turntables Rotate turntables for directing locomotives.
Operations Cargo and crane operations Drive cranes, loaders, or hoists for industrial scenes.
Structures Drawbridge movement Raise and lower drawbridges or lift bridges.
Structures Engine house doors Open and close engine house or workshop doors.
Structures Station platform doors Simulate platform doors synchronized with train arrivals.
Scenery Animated scenery elements Animate windmills, water wheels, cable cars, or similar features.
Scenery Pop-up scenery Trigger pop-up figures, animals, or scenic elements.
Scenery Variable terrain Adjust terrain elements such as mine elevators or water levels.
Scenery Scenic effects Create dynamic scenic motion effects.
Scenery Diorama movements Add motion to diorama scenes for enhanced realism.
Vehicles Moving vehicles Control steering or motion of road vehicles.
Facilities Load/unload mechanisms Automate loading and unloading of cargo.
Facilities Track cleaning Operate track-cleaning mechanisms.
Information Station announcement boards Animate mechanical or visual announcement boards.
Infrastructure Rotating antennas or dishes Rotate radar dishes or antennas for industrial or military scenes.

Planning Context

Servo planning begins when you decide what elements of the layout should move and why. Each servo-controlled device should exist for a clear operational or scenic purpose, such as controlling turnouts, operating signals, animating scenery, or enabling interactive features.

Planning involves determining:

  • Which layout elements require precise or repeatable motion
  • Whether movement is operator-driven, automated, or both
  • How many servos are needed and how they are grouped per card
  • Physical placement of servos relative to the mechanisms they drive

Uses

The table below lists common planning use cases that drive the need for this card. Each entry represents a reason to introduce this capability into a layout design.

References

Last updated on: January 12, 2026 © 2026 Pat Fleming