hello
this is my diy cnc from scratch :
pic16f88 servo pid step driection controlled mach3 or emc2 (the encoder i used are from old deskjet printer)
anyone interested can email me
https://www.youtube.com/watch?v=quLhph8qKFM
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hello
this is my diy cnc from scratch :
pic16f88 servo pid step driection controlled mach3 or emc2 (the encoder i used are from old deskjet printer)
anyone interested can email me
https://www.youtube.com/watch?v=quLhph8qKFM
Beautiful work! For movement, why don't you push it faster?
Any plans to release the pic servo code? Good work!!!
for my design i can go to 1000 mm/min in three axis that the safest way for the first attemp with acceptable error
to increase speed i can change the axes with higher pitch or decrease the reduction
i beleive i can reach 3000mm/min with same electronic design and play with gears or axis
i will post design soon and hex soon
thanks
Great work :)...Will happy to see closeup pictures of encoder...
Also i see the encoder wheel but can you tell us where you get the encoder from?..can u post closeup picture of the encoder? what brand printer is that?
Did you program in C or Assembly?
Al.
programming is done in C with ccs compiler
the programme handle encoder resolution 1X to incremente timer0 and timer1 to get the count
it also able to tune P.I.D, max error , integral anti_windup,pwm_min,pwm,max through rs232
also enable/disable input and error output (case error too large)
it also handle current limting independant of µc
i will post picture of the encoder
all inkjet printer has encoder wheel (arrount 1400 ppr) an their quadrature reader ( 6 leads)
also they have linear strip encoder (about 30 cm length) can be used for z axis
hello again
this is the schematic i rush it little bit but it can give you idea about the hardware
Looks good! I use CCS compiler too and would like to see the code if possible. I have a few f88 boards laying around. It
ahsameh: Is there more info, I would like to build my own servodrivers.
If you want an open source PID servo controller, which is also available as a very low cost kit, this one is released, tested, and works:
BOBPID1: PID Servo Controller massmind
I don't know if anyone is still doing anything on this but this looks pretty interesting. My only problem is the lack of an H bridge that would support a 90 volt servo with a 120 volt input - has any seen something like this that would work with this board? I'd love to look at using these and an Acorn board to retrofit a mill that I have -
Best I can do is 40 volts:Quote:
Originally Posted by SEK22Hornet
DRV8701: 1HP DC Motor H-Bridge Driver massmind
But the BOB PID can run any H-Bridge that supports a PWM and Direction input.
BOBPID1: PID Servo Controller massmind
And can be modified to give 0-10 volt output signal in place of PWM.
A modification to support +/- 10 volt signaling is in the works, as is ENC / RC output. It's all open source, but the repo isn't up to date so talk to me if you want to make changes.
I made a120vdc H-bridge based on Tahmids iR2110 Tahmid's blog: Using the high-low side driver IR2110 - explanation and plenty of example circuits you just need to size the Mosfets accordingly.Quote:
Originally Posted by SEK22Hornet
Al.
was hoping to find something that didn't require a pcb layout - but the article looks pretty good. Right now in the middle of getting my new old Partner 1 Milltronics VM-17 up and running so this will go on the back burner.
Hey Al, do you have a sense of what the component cost was for that driver? I'd be interested in making a kit available if the price could be made reasonable.
I would have to look up my old Digikey invoices, I used a Pic 18F23K22 and communicated with RS485 serial Modbus type interface.
120vac mains powered with isolation for the 5v logic.
Al.