Touch-Controlled CNC Router

An educational tabletop CNC router, with a radically rethought touchscreen interface.

What is the Touch-Controlled CNC Router?

The Touch-Controlled CNC Router (or TouchCut Pro) is an educational, table-top CNC router that redefines the interface between human and machine in Computer-Aided-Manufacture.

Material is clamped inside the machine, and a live image of the clamped material is shown on the touchscreen. Using an intuitive MS Paint-style interface, the user draws cutting paths onto the image of the material. They press Start and watch as the machine cuts out exactly what they drew, where they drew it, and how they drew it.

Kinematic Association

For a product present in most households, the mechanics of a printer are, in general, poorly understood. It is not a hugely complex device, but the user's actions are too far removed from the result to understand the linking process. The printer might as well be a magic black-box, likewise with CNC machines.

TouchCut Pro is different. The lines you draw, are the same lines that you see being cut, and it is this direct connection or kinematic association that makes the complex CNC machine almost trivial to understand. The working product is genuinely inspiring to use; it is also functional, and provides a platform for experimentation to understand more complex aspects of CNC manufacture.

Cutting Demonstration

The working prototype. Blue foam was generally used for demonstrations to save cost and time, although the router could also cut other materials e.g. wood.

Mechanical Construction

The frame is constructed from aluminium extrusions and two 10mm aluminium plates. Lead screws and linear bearing rails are used for robust 2.5 axis motion.

Electronics

The prototype used a touchscreen Windows tablet and a standard webcam. These interfaced with an Arduino Mega 2560 and a RAMPS 1.4 board, which controlled the stepper motors, limit switches, and a standard hand router spindle via a modified relay.

User Interface

A prototype of the MS-Paint style interface was written from scratch in Python using Tkinter. The program manages material and machine set-up, converts line and shape drawings into G-code, and interfaces with the Arduino which runs the open-source G-code executor, Grbl.

Team Project

This was a team project. I [centre] led concept development, before designing and prototyping the UI, back-end software and electronics. Rory [left] led mechanical design and construction, and Akhil [right] developed the portfolio and theoretical business strategy.