Utilizing the ESP32’s Processing Power to Run Grbl CNC Software

When it comes to DIY three-axis machines, Grbl is one of the most popular CNC controllers available. It is an open source software package used for the controlling of machines and will run on an Arduino. However, in doing so, the Arduino becomes incapable of performing and handling any other tasks you may wish for it to do. In other words, the software takes up all the available code space on an Arduino leaving no room for future expansions and improvements.

One of the new popular boards that is a big hit in the maker community is the ESP32. These can be programmed using the familiar and user-friendly Arduino IDE and also come with much more capability than the standard Arduino. For starters, it has a 32-bit processor compared to the Arduino’s humble 8-bit processor. In addition, it has more flash and RAM as well as all the necessary circuitry to enable WiFi and Bluetooth connectivity. All this along with good price point makes these boards prime candidates for running Grbl in a similar way Arduino does.

Once the right ambitious hackers came along a port of Grbl from the Arduino to the ESP32 platform is exactly what happened. This was notably done by Bart Dring, a somewhat CNC enthusiast. Now an equivalently ambitious maker is working on a project consisting of developing an ESP32-based circuit card for CNC machines. The goal is to be easy and convenient to use and also work with a wide variety of CNC machines, from the hobbyist to the professional machine.

The solution consists of two circuit board designs. A motherboard and an expansions board. The motherboard will be necessary for a CNC development whereas the expansion board will allow users additional GPIO and direct control of lower power stepper motors. Furthermore, the motherboard will come equipped with a master potentiometer override for cutting speed and another master potentiometer to override the real-time spindle feed. These master overrides allow the user to build confidence when starting new jobs and also make the process much safer.

A lot of progress has already been made in the development of the project. Prototypes of the boards have been made and proven out and the PCBs themselves have been designed, manufactured, and shipped. The next steps involve lots of soldering, assembly, and testing. To stay up to date on the project be sure to check out the blog at cnc4fun.com.