Firmware on Arduino to Drive Servo Motors for Galvo Scanning Laser Engraver

[marinusdebeer]

Hi,

We are engineers in our final year of university, for our capstone design project we are building a Galvo Laser Engraver. We have built the enclosure and have all the major components like the servo motors, f-theta lense, 20 Watt laser, powersupply, arduino mega, all the mirrors, and enclosure materials. We are just looking for the firmware on the control board (aka arduino if possible) to drive the servo motor drivers. We were first planning to use GRBL but then realized it is only compatible with stepper motors. Do you have suggestions on what firmware we can use??

On the computer side we are thinking of using Mach3, LinuxCNC, or laserGRBL to take in an image as the input and output g-code to the control board.

Thanks,
Marinus

[VDX]

... use servo motors (or steppers) instead of the galvos - then any CNC-software+driver combo could be used ...

Viktor

[marinusdebeer]

The thing is I already bought the galvos for $650 so I really want to use them. Plus I want to use an arduino but if it really isn't possible to use an arduino then I will look for a different board that can perform the task.

[VDX]

... for XY-galvos I'm using the E1701D from HAlaser - http://halaser.de/e1701.php

And did some "tinkering" with this super-cheap cinese galvos, an Easylase LC USB and programming a flow-plugin for BeamConstruct ...

Viktor

[lasermaster1977]

The thing is I already bought the galvos for $650 so I really want to use them. Plus I want to use an arduino but if it really isn't possible to use an arduino then I will look for a different board that can perform the task.

Yes, it is certainly possible to use an Arduino for your project. Look on hackster.io for a project using an Arduino Uno as a CAM controller for a pen plotter. You will find many examples although none of them are using XY scanners and all of them use stepper motors for XY axis control. https://www.hackster.io/search?i=pro...CNC%20projects

Many years ago, I used a pair of G120PD scanners and a 1 watt Coherent mixed-gas ion laser for business card/wood burning engraving experiments. They worked great as a novelty for full scan angles < 15 degrees as long as sharp focus is maintained at point of beam contact with medium.

Good luck, and have fun!

[serkang]

Hello could you find firmware? I need to like you. Could you help me ?

[radbis]

Hey,
Currently, there are no commercial or open source firmware for the fast XY2-100 protocol running under Arduino. As Viktor wrote, the best and perhaps the cheapest solution is to buy a module from HAlaser or a slightly cheaper Chinese module from Ebay.
It is true that there is one proof of concept solution done at the University of Seoul, but apart from the short document I got to, they did not give any details.
The main difficulty in writing such firmware on Arduino is the low clock frequency. According to the specification, all X / Y / Synch control signals should be synchronized with the 2MHz clock signal. In Arduino UNO it is very difficult. In Arduino DUE it would be easier.
That's why colleagues from HALaser did it on the basis of a much faster BeagleBone, I think.
You can also find the concept of software and electronics based on STM32 on the network, but also without details. Such things are usually kept secret and then put into sale.
Another impediment is the size of the memory. The solution is the earlier processing of vectors on the PC and only sending them to Arduino, which in turn through the XY2-100 protocol will drive the head with galvanometers such as eg ScanLab or Raylase (I have this). The second way is to add memory modules to Arduino. Then: send the unprocessed vectors to it and then store them in memory after processing. Then it is already taken from memory and sent after the protocol to the head.
In April, I started working on the Arduino Uno firmware, which I finished in June. I managed to write a software to convert the GRBL code to XY2-100 at the required speed. Correctness checked on a digital oscilloscope. Unfortunately, since the summer holidays I did not have time to put everything together and connect it to the scanning head. Also some fixes like CRC must be done before final version.
There is a chance that after Christmas, the project will appear on Github under the GPL license. I just need to find time to return to programming and finish it in a usable version. I am also considering the option of selling programmed and ready to run ATMega328p chips in DIP package, together with documentation on how to connect them to XY2-100 protocol heads.
I will see what suit better for me.
Best regards
Radek

[VDX]

Hi Radek,

good luck!

Viktor