I agree.. It is so easy isn't it? Just use a ESP32! I tried to write a machine controller when I was in my 20's... This was before I found turbocnc (which sucked) and linuxcnc. (emc1)
I also helped test the trajectory planner improvements made when Rob added n-segment read-ahead. It took months to make something viable that also worked as an actual cnc (tool offsets, velocity/acc constraints, cnc stuff...) Someone that comes in and says - you can easily use x and y to make a great cnc controller are quite naive... The grbl controller that every one touts as a great solution is so basic it is scary.. works great for a basic 3 axis mill - but that is it. I have actually been using a rpi4 and mesa to run an actual mill to machine actual stuff. It works very well - no issues... It does some amazing stuff like... (and is an actual cnc controller that takes actual gcode..) Am I getting my point across? https://www.youtube.com/shorts/23bEsKMNJH0 sam On Sat, Aug 5, 2023 at 7:30 PM John Dammeyer <jo...@autoartisans.com> wrote: > Chris, > I must admit I had a bit of a chuckle when I read your answer. It's so > easy to just do this or use that or add these and then you are good to go. > > If it's that easy I expect you'll have that tablet with the wifi > connection to the ESP32 and be executing G-Code by the end of August right? > > Other than wiring up motors and all the mechanicals, which has to be done > for any CNC installation the time to get the CNC running was even less time > than from now until the end of August for me. And I likely would have been > using this were it not for the inverted ESTOP. > https://youtu.be/9GF709ZfLRQ > Instead I went the PC route and did a dual boot between LinuxCNC and > WIN-XP for MACH3. After that I bought the MESA 7i92H after also mucking > around with my USB SmoothStepper (MACH3) from my CNC router. I decided > Linux had a better future than WIN-XP so although I still run MACH3 on the > CNC router the mill has LinuxCNC. > > On the workbench I muck around with a Pi4 and MESA 7i92H. Go onto you > tube and search Raspberry Pi and LinuxCNC and there are lots. > Again one like this is much faster to set up than your suggestion and not > any more expensive. > https://youtu.be/qL530kJUmII > > I do look forward to your progress on that novel idea of a tablet, ESP32, > RTOS and all the code to deal with trajectory planning. > Keep us informed. Maybe some videos of the intermediate steps. > Especially since as you imply it's so easy to go that route. > > It would be interesting if you could do it for less than > https://youtu.be/X-DY6iL6NcI > > John > > > > -----Original Message----- > > From: Chris Albertson [mailto:albertson.ch...@gmail.com] > > Sent: August 5, 2023 4:02 PM > > To: Enhanced Machine Controller (EMC) > > Subject: Re: [Emc-users] Beaglebone black latency > > > > Why start with a BBB/Pi4 and then add a screen and so on. > > > > A better starting place would be a low-cost Android tablet. Perhaps > like this > > one. For $120 you get the CPU (that runs Linux), a touch screen and > WiFi. > > What is needed is a way to connect it to a machine tool. > > https://www.bestbuy.com/site/samsung-galaxy-tab-a7-lite-8-7-32gb-with- > > wi-fi-dark-gray/6464584.p?skuId=6464584? > > Samsung Galaxy Tab A7 Lite 8.7" 32GB with Wi-Fi Dark Gray SM- > > T220NZAAXAR > > bestbuy.com > > > > I would use something like a small 32-bit micro controller to do the > real-time > > pulses and switch monitoring. If you would choose an ESP32 then the > > interface to the tablet is wireless. But you could use USB as both > devices > > have USB built-in. USB has a built-in asocronus mode where data moves in > > strict real-time. But this might not be needed if 100% of the RT loops > are > > onthe microcontroller. > > > > The ESP32 is a dual-CPU, 32-bit device with more then enough computer > > power to run a CNC controller. I would 100%, for sure run an RTOS > > (FreeRTOS or Mbed) on the ESP32. The tablet is just the user interface > and > > �MPG�. > > > > I am currently using ESP32 to generate PWM control for a 12-axis robot > and > > I�m getting sub microsecond pulse accuracy which is more then my > > application needs. It is very fast and written 100% in Python. > > > > If the user already had an Android tablet or wanted to buy a used tablet > you > > really could under cut the cost of a $500 Chinese device. > > > > LCNC was written to take advantage of �cheap� community hardware. This > > is when a basic 16-bit PC would sell for �only� about $3,500. Today�s > > commodity hardware is called a �cell phone� and they are MUCH more > > powerful then the old PC was. > > > > > > > > > > > > > On Aug 5, 2023, at 3:23 PM, John Dammeyer <jo...@autoartisans.com> > > wrote: > > > > > > Me too. A closer look at the fine print and selecting the correct > button > > shows the actual CNC controller is $513 or $541 for 3 or 4 axis > respectively. > > The MPG is priced separately at $96. > > > > > > And this is why a BBB with a cape that included a Break Out Board with > a > > few relays etc. for under $100 would be quite the bargain. The question > is > > then what sort of display would be good. And you still need some sort of > > MPG to go with it for also about $100. > > > > > > For $94 I can get, from amazon.ca a 7inch HDMI LCD (H) 1024x600 > Monitor > > IPS Screen Capacitive Touch Display Supports Raspberry Pi Jetson Nano > > BeagleBone Black Banana Pi & Microsoft XBOX360, Sony PS4,Nintendo Switch > > > > > > And therein lies the problem. Creating something similar to the $500 > > Chinese CNC controllers with touch screen will ultimately cost in the > same > > $500 range. But unless the MachineKit or LinuxCNC version is stable > with a > > target life similar to the life of the machine tool no one will spend > the energy > > and time to make that. > > > > > > The market isn't big enough to justify the work required. Which is > why so > > many of the Beagle Capes are no longer available. Next week there's an > new > > ESP32 with more bells and whistles. Won't do what the Beagle does but > ... > > > > > > John > > > > > > > > >> -----Original Message----- > > >> From: Martin Dobbins [mailto:tu...@hotmail.com] > > >> Sent: August 5, 2023 11:44 AM > > >> To: Enhanced Machine Controller (EMC) > > >> Subject: Re: [Emc-users] Beaglebone black latency > > >> > > >> It makes me wonder which operating system they put on that Chinese > > >> controller, and what motion control system. > > >> > > >> Martin > > >> > > >> ________________________________ > > >> From: John Dammeyer > > >> Sent: Friday, August 4, 2023 7:41 PM > > >> To: 'Enhanced Machine Controller (EMC)' <emc- > > >> us...@lists.sourceforge.net> > > >> Subject: Re: [Emc-users] Beaglebone black latency > > >> > > >> My biggest issue with the Xylotex BBB Cape for CNC was that the logic > for > > >> ESTOP was inverted. ESTOP was a N/O switch so if a wire was broken > you > > >> wouldn't find out until you tried to save a body part from being > injured > > with > > >> the ESTOP. > > > > > > > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
