Thanks SJH It looks like I need to look at the C programming. I will have a look at the move instructions and the SetBet/ReadBit etc. Any ideas on how to keep counters in Non volatile memory and to read them from a PC app? We need to count the number of cycles, measure the cycle time and then retrieve that in some way from a PC. Regards Eon From: DynoMotion@yahoogroups.com [mailto:DynoMotion@yahoogroups.com]
Sent: Sunday, 02 August 2015 21:24
To: DynoMotion@yahoogroups.com
Subject: Re: [DynoMotion] Using KFlop for machine automation Well I'm not Tom, but here's what we do which might be of some help to you regarding your first question. Our machine is a conventional CNC mill, but it can also run in a limited autonomous "manual" mode whether or not there is a PC connected. Basically, it allows homing and jogging the axes using an MPG handwheel. The way we have architected it is to put most of the kflop software in a single program running as thread 7, and have that thread configured to run at power-up time. That program runs all the time (in a loop) and waits for various I/O signals. When a signal occurs, it runs appropriate routines within itself. So that takes care of your requirement to automatically INIT at power-up, and you could automatically HOME (or wait for a PLC signal etc. to home). Actually running G-code autonomously is something we have not required. It currently requires a PC connected and running the interpreter. Here's a few approaches I would consider, from easiest to hardest: - If the signal to start the g-code comes from a PLC, then attach the PLC to the PC (somehow) and modify the PC CNC program to execute g-code on command. - otherwise, if the PLC connects to the kflop, then the kflop can be programmed to signal the PC to start running the g-code. - forget g-code, and write some kflop C code which directly performs the motion you want (using the Move() functions etc.) For a robot application, this would not be too difficult since (presumably) you don't need super accurate path following, but reasonably accurate timing and end-points. - Port the g-code interpreter code to run directly on the kflop. Thread 7 can run up to 320k of code, so this would be theoretically possible (I once ported the NGC interpreter to a device with only 256k flash memory). The g-code would also need to be flashed in, as a big string constant. One advantage of getting rid of g-code is that the full power and versatility of C may be brought to bear, and you can completely ditch the PC and its associated MTBF. As you are aware, g-code has very limited ability to react to real-world conditions. If your application has any sort of feedback (such as force sensors, proximity detectors etc.) then C would be a good choice.
The down-side is the amount of engineering man-power required for development and maintenance. It's hard to compare apples and oranges, but from our experience implementing touch probing routines, C emulating g-code takes 5-20 x the effort of real g-code. (We split our probing into a C routine which takes care of the math and low-level choreography for probing the center of a sphere, and a g-code program which coordinates multiple sphere probes - this seemed the optimum split for our requirements). Maybe I'm biassed as a C programmer, but I find C code to be more maintainable and understandable than the equivalent g-code. Compare these: #45 = [atan[#38+#14]/[#37] + #16] a_angle = RAD_TO_DEG(atan2(pos_y + offset_y, pos_x)) + offset_a; Regards, SJH On Sun, Aug 2, 2015 at 4:09 AM, eondekoker@... [DynoMotion] <DynoMotion@yahoogroups.com> wrote: Hi Tom We are building an robot for doing packaging and we have the basics running in G-Code. We need to do the following next and need to know what would be the best strategy: 1) Using the G-code screen is fine for prototyping. But ideally we would like the machine to operate autonomously without requiring the operator to Press buttons for Init, Home and to start the G-code. What would be the best way to do this? 2) We would like to keep some statistics such as a counter and time stamp on the number of operations. One can define parameters in G code for counting but is there a way to do the time stamp and write this to a file? What would be the best way to do this? |
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