RC Snowcat – Custom 3D Printed Tracked Vehicle (V1 Prototype)

RC Snowcat – Custom 3D Printed Tracked Vehicle (V1 Prototype)

Project Overview

The goal of this project was to design and build a fully functional, compact RC snowcat optimized for real-world performance in snow—not just appearance. While scale accuracy wasn't the top priority, the target size was roughly 1/24 scale (SCX24-sized platform) to keep it small, lightweight, and maneuverable.

From the beginning, this build focused on functionality, control, and deep-snow capability, while still maintaining a unique, futuristic design.

Core Design Requirements

• Roughly 1/24 scale footprint (~100mm body length)
• Powered by N20 geared motors
• Tank steering (independent track control)
• Functional front blade with:
  • Up/down motion
  • Left/right angle control (dual-axis)
• Designed to perform well in deep snow
• Fully custom electronics, including:
  • Custom PCB (KiCad)
  • Wireless control via Xbox controller (BluePad32)

Mechanical Design

Tracked Drivetrain

The snowcat uses two N20 motors per track, giving it enough torque to move through snow while maintaining a compact size.

A major challenge was track geometry:

• Early versions had narrow tracks and wide body → poor performance
• Final design prioritizes:
  • Wider tracks = better floatation
  • Narrow track spacing = less high-centering

To achieve this, the motors are mounted inside the tracks themselves, which was a key breakthrough in the design.

Blade System (2-Axis Control)

One of the main differentiators of this build is the fully functional blade:

• Vertical movement (up/down):
  • Custom-built linear actuator
  • Uses a threaded N20 motor
  • Designed because no off-the-shelf actuator was small enough
• Horizontal steering (left/right):
  • Direct-drive N20 motor
  • Simple, strong, and compact solution

This dual-axis blade was important because most small builds only include vertical movement, which limits real usability.

Electronics & Control System

Custom PCB (KiCad)

Instead of using off-the-shelf RC electronics, this build uses a fully custom-designed PCB:

• Acts as a compact control hub
• Designed to minimize size while handling:
  • Motor control
  • Power regulation
  • Microcontroller integration

Surprisingly, the PCB worked first try, despite being a complex part of the project.

Microcontroller & Input

• Uses a Seeed Studio microcontroller (XIAO series)
• Chosen for:
  • Extremely small size
  • Enough performance for real-time control

Control is handled through:

• BluePad32 (Bluetooth controller library)
  • Allows connection to:
    • Xbox controllers
    • PlayStation controllers

This gives the snowcat a much more intuitive and modern control system compared to traditional RC transmitters.

Motor Control & Power

• Two 5V motor drivers control the tracks (PWM-based forward/reverse)
  • Enables:
    • Smooth throttle control
    • Tank steering
• Powered by:
  • 3.7V battery
  • 5V boost converter for stable electronics power
• Includes decoupling (coupling) capacitors:
  • Help reduce electrical noise from motors
  • Improve system stability

Design & Aesthetics

The exterior design was inspired by real snowcats but intentionally not a direct replica.

Goals:

• Futuristic, angular look
• Clean geometric shapes
• Functional packaging (must fit PCB and components)

The result is a design that balances:

• Functionality
• Manufacturability (3D printing)
• Unique visual identity

Development & Iteration

This project involved heavy iteration, especially on mechanical components:

• Frame: ~10 iterations
• Tracks: ~3 major redesigns
• Blade system: multiple refinements
• Electronics: surprisingly successful on first PCB revision

Everything was:

• Designed in SolidWorks
• Prototyped on a home 3D printer
• Built entirely from scratch (no borrowed designs)

Challenges & Key Learnings

• Packaging is everything at this scale
• Track geometry has a huge impact on snow performance
• Off-the-shelf parts don't always exist → sometimes you must design your own (linear actuator)
• Custom electronics drastically improve integration, but increase complexity
• Iteration is unavoidable—especially for moving mechanical systems

Current Status (V1 Prototype)

This is a fully functional Version 1 prototype:

• Drives reliably
• Blade operates in both axes
• Wireless controller works
• Performs significantly better in snow than early versions

However, there's still room for improvement:

• Refining durability
• Improving track efficiency
• Cleaning up wiring and packaging
• Further optimizing weight and balance