I have done several pen and laser machines lately, so I decided to create a custom PCB for Grbl_ESP32 for these types of machines. This is a small (70mm x 60mm) PCB with all the features a pen plotter or laser cutter/engraver would need.
These typically use stepper motors for the X and Y axes. On pen plotters, the Z axis is controlled by a servo or solenoid. On lasers you need an accurate PWM for laser power control.
Here are the features of the PCB assembly
- (2) Stepper Motor Driver Sockets for standard stepper driver modules.
- (1) Hobby Servo Connector.
- (1) High Current (10A max) Output Control. This can be used for a solenoid, fans, etc.
- (2) limit/Home Switch Connectors.
- Laser Power PWM connector
- Removable Micro SD card. Upload files via Wifi to reliably run off-line.
- 5V 3A Step Down Power Supply
- Standard DC Barrel Connector for power input. (9-28 VDC)
- Power Output Connection for laser module.
Grbl_ESP32 Advanced Features
- 32-Bit dual core processor
- Fast 120kHz step rates
- Access point or station modes
- Complete web user interface
- Bluetooth Serial
- Compatible with phone apps
- Compatible with most serial port gcode senders
- 16 bit laser power control.
- Core XY kinematics supported for T style machines.
- RTOS (real time operating system) allows the use of custom tasks.
- Precise servo control accurately mapped to Z motion, plus interactive calibration.
- Precise control of solenoids via adjustable pull and hold strengths using PWM. This allows a strong pull, yet a cool hold temperature.
- Instant On/Off – Unlike a Raspberry Pi, there is no long boot time or formal shutdown required. It is typically ready to go in a few seconds.
How to control it
There are several ways to connect to the controller, but to run jobs, you basically either stream the gcode or run it from a file on the SD card. The SD card is a great feature because it is free from connectivity interruptions and you don’t need to stay connected to your machine while it is running the job. You can quickly upload files via WiFi or remove it and plug it into your computer.
Read more: DIY Pen/Laser Engraver ESP32 Controller