3D Printed Sprocket & Track Unit
Design Documentation | Domechy Design Library | DCY-01
Download the Full Documentation PDF
This page is a summary. For complete details, diagrams, and equations, download the PDF below.
Overview
This documentation introduces a modular 3D-printed sprocket and track unit designed for small DIY robotics projects. The system consists of interlocking track links and matching sprockets. Applications include hobbyist robots, educational platforms, and prototypes.
This mechanism is used in my project: DZ01: DIY 3D-Printed Tracked Mobile Robot
Design Element
Part
Function
Notes
Drive Sprocket
Connected to DC motor, drives system
Solid center hole
Idler Sprocket
Freely rotating sprocket
Hollow center hole
Track
Transfers motion between sprockets
Made from multiple track links
Track Link
Small link that forms the track
Interlocking design
Mechanical Design
Sprocket Design
General considerations include pitch, Pitch Circle Diameter (PCD), and number of teeth.
Smaller pitch gives smoother track motion. For 3D printing, tolerance must be considered.
P = PCD × sin(180°/N)
PCD = P / sin(180°/N)
Track Design
Each track is built from multiple interlocking links joined with filament. The link pitch matches the sprocket pitch, and the roller diameter should be equal to or slightly smaller than the sprocket rollers for smooth operation.
Assembly
The drive sprocket mounts directly onto the DC motor shaft, serving as the reference point. The idler sprocket rotates freely on its shaft. Both shafts are supported by a simple frame plate, which can be adapted into a robot chassis. The sprocket spacing is determined by the pitch calculation.
Testing & Iteration
The sprocket and track unit was mounted to a DC motor and tested. Motion was smooth with no slipping.
Future iterations will use TPU for the track and PETG for the sprockets to increase grip and durability.
Notes & Tips
Shorter sprocket pitch gives smoother track motion.
Ensure proper tolerance when 3D printing interlocking track links.
Sprocket and track grooves help keep the track aligned.