Zenbot/Gecko/LinuxCNC?

First, thank you for your time. You are really helping me gain an understanding of the terrain. I'm an experienced firmware engineer and DSP guy, so I understand all the concepts just fine. But learning the specifics is really helpful.

I'm completely open minded to a Mini-ITX x86 motherboard. But are you including the cost of CPU and RAM and diskless storage? If so, please send some links! When I've looked before, it's added up quick.

Based on what you saying about the BBB PRU, I'll go learn something about that. Since it's onboard, I would presumably be able to use RTAI and that would be more conventional. There is a lot to recommend the road more travelled. My primary goals here are a) make the machine control part of the machine rather than being a separate laptop or desktop PC and b) keep it affordable. Otherwise I would just go with UCCNC and hold my nose about Windows and its bloat and virus proneness and cost.

About the only graphics I need would be to render the machine path in an overview once (no animation). That's what Mach3 does and it is handy.

I'll be getting in touch with the MachineKit guys, but would it be safe to assume that their PRU step generator drivers will work with LinuxCNC, even they are not included with LinuxCNC?

The BBB solution is looking very attractive to me, so I'll investigate it. I've already got the BBB, so the cost to me is zero, and not needing a Mesa I can just explore that for the price of my own time. I've been down the Linux open source road before, so I know that success is far from guaranteed. But it is worth a little time. If it works it will be slick, even if it is not good for any realtime visualization of machine paths.

I'll report back or have more questions, but for the time being I'll head off to the MachineKit forum.

Hi,

I've been over to the MachineKit forum, and that option is not looking attractive, mostly because the PRU pins apparently cannot interface directly with my Gecko, so I'd have to build some sort of interface. It's certainly something I could do, but my project time needs to go into what I can do with my CNC, not my CNC itself.

Also everyone seems to think I should still have an external PC because of "the graphics". I'm still confused about why that is an issue, but sometimes it is good to listen to people.

If I need an external PC or an embedded board that isn't much cheaper, then I want to interface with my CNC with ethernet or USB because it is more flexible. But seems to be exactly where LinuxCNC seems to be weak.

Wouldn't it be nice if I could get a Chromebook, convert to linux and the hook up to the PC with one of these?:

www.amazon.com/Parallel-CNC-Motion-Contr...icense/dp/B07692WLB7

Alas, it is sounding more and more like a "can't get there from here" situation. At least not easily. I may have to tolerate Windows, run UCCNC, buy one of the above and be done with it. Maybe LinuxCNC will be more USB and ethernet friendly down the line a bit.

Does that make sense?

Indeed, if I had another PC sitting around to put Linux on, it would make sense to try the Mesa solution, and I think I'll look around for one. I may be able to find an old one for free, and I still really like the idea.

But I already have a laptop running Windows next to my CNC, and I'm kinda afraid of converting it to Linux, because of all the funny drivers that you typically need for a laptop. Maybe Linux is better about that these days, or I could do a live boot from a USB drive. That especially is worth considering.

I don't get why I would use MachineKit with a 7i92. Why wouldn't I just use the latest LinuxCNC and make sure I have the right kernel?

The most interesting part of your reply is your comment about having "a better solution". Do you say that because it is Linux or because you think the LinuxCNC experience is superior to the UUCNC software experience? If the latter, that is additional motivation to consider LinuxCNC.

I started thinking about USB because of the Chromebook option, but more and more laptops especially don't even have ethernet ports anymore.

When I was looking at a platform for a CNC machine with no knowledge of anything, despite having a mate who loves in the same street that has 2 Mach3 machines willing to help me, I could not bring myself to use it. It was old, there were few PCs still around that had parallel ports and the whole Break out board system seemed to be very limiting. So there were no compelling reasons to purchase obsolete software that was not going to run on current hardware.

LinuxCNC seemed to be the most logical choice due to the lack of real time support in Windows that required expensive hardware (eg. smoothstepper) to work around. Even then the performance is only 1/3 of what can be achieved with Mesa hardware. I ended up purchasing a Mesa 7i76e ethernet card. For a PC, I am using a Gigabyte J1900 USFF PC which cost AUD $100, the same as a Beaglebone Black. Another $100 for the smallest memory chip I could purchase (4gb) and a 120 Gb SSD and I have a perfect platform about 5" square that is attached to the back of my touch screen monitor. Whilst this is a perfect solution for me, I also do like Andy's approach of treating a small PC Motherboard as just another component to wire up in the control panel.

I will say it was hard to get the prempt_rt kernel installed but the guys here helped me all of the way. Now there is an excellent tutorial on the forum here and also now a preempt_rt ISO image that you can use so its even easier again.

I'm a fan of Arduinos, Blackberry's and the like but, they have too many limitations for CNC work. Once you get you get your head around Linuxcnc's HAL files (which should be pretty easy for you as you can migrate your mach config.) it is a rich environment.

In my view, LinuxCNC's real strength is the ability to extend the system by writing HAL components in C and installing them in seconds to extend the HAL environment.

Finally those on this forum I've seen make the switch from Mach/Windows to LinuxCNC are well pleased with the decision and their satisfaction seems even greater where they've used Mesa in the mix.

Everyone on both this forum and the machinekit forum have been extremely helpful. I've also been corresponding with a friend who has used Mach3 and UCCNC and LinuxCNC. He currently uses UCCNC.

My current view of the situation is as follow. First, Mach3 is dying and I haven't heard anyone say anything good about it. It served a purpose at one point in time but that time is passed. That makes it a shoot out between UCCNC and LinuxCNC.

My sense is that LinuxCNC is incredibly powerful and customizable. But the flip side is that the learning curve is steep, and from what I've heard and from looking at the documentation, it isn't great. The forum is super helpful. So for someone who is a power user or is building custom setups, LinuxCNC is the clear choice.

UCCNC on the other hand is less flexible, and because it runs on Windows it is not suitable for embedding in a commercial product like many vendors do. On the other hand it is easier to set up for standard configurations, easier to customize the UI, and because they also make the ethernet interfaces, it should be pretty plug and play. And the docs are going to be better because it is not as vast but also because it is a commercial product. So it is probably better for a "standard user" who just wants things to work with minimal startup time.

Since I really fall into this second category, I'm reluctantly leaning towards UCCNC. I say reluctantly based on just wanting to get away from Windows. But I can't justify extra startup time and learning curves and so forth logically. And the licensing cost of Windows turns out not to be barrier, because as has been pointed out on this forum, refurbished desktop PCs are dirt cheap, and they include a Windows license.

If I were building and selling routers, or doing something really custom, I'd for sure use LinuxCNC.

Is this summary fair?