OpenSBP, a simple, free standard for CNC machine programming

The people behind the ShopBot CNC routers have opened up their OpenSBP language so that other CNC manufacturers can use it. Jeffrey McGrew explains why this is good:

Why this is huge is that there isn’t a standard in this world. The closest you get is what people call ‘G-Code’, which is old, broken, and wasn’t ever meant to drive complex CNC machines. ‘G-Code’ was simply a subset of a computer standard to drive sevro-driven and map-making machines forty or more years ago. There were ‘N-Codes’ and ‘T-Codes’ and more, but the ‘G-codes’ were the ones that made the machine move. So, like ‘G53′ was a command to make the machine move a certain way. It was standardized in the early 60′s, and then didn’t change. That controller code was, more or less, hacked for more complex CNC use a loooooong time ago and it’s only gotten worse. The G-code for one machine won’t work with another machine, there are all sorts of machine-specific codes and controls, and it’s not human-readable.

So, enter Shopbot. They decided (wisely I feel) to forgo the whole G-code mess, and instead make their own command structure. SBP, as it’s called, is more or less a simple form of Basic or Logo. It’s much easier to use, much easier to write or deal with, much easier to read, and has all the things one would want in a proper computer language such as subroutines, loops, inputs, and more.

1. [duallain]

   The, “ShopBot CNC routers” link, links to gadgets.boingboing.net.

2. [Anonymous]

   A simple form of basic or logo? Those are way different languages…

3. [adralien]

   I would heartily argue that G-code is -not- broken… it’s not perfect, however.

   I purchased a 1990′s CNC with a DOS box built in that understands most G-code… it’s amazing that I can easily write programs to run on it, even though it only has 512K of memory in it.

   For comparison, try to get tools to write code for an old palm-pilot… dead links and dependency hell.

   You see, G-code and machine manufacturers standardized and it worked reasonably well, to the point where I can run an ancient piece of hardware with no memory from a modern computer using “drip feed” where it loads 20 lines at a time, then discards them.

   I’ve used this to run 50,000 line programs I’ve written with my own Python-to-G-code routines. Its still a still very usable CNC that can run any G-code from any modern 3D program. Every major 3D program has a post-processor for my machine (dynapath Delta 20)

   So, yes, old, but not broken. Not by a long shot.