Schaublin 125-CNC retrofit.

More
23 Feb 2021 07:50 #199802 by RotarySMP
Since these resolvers are reported to be the wrong style to integrate with these Granite drives, I guess that is a dead end.
Mark

Please Log in or Create an account to join the conversation.

More
23 Feb 2021 09:20 #199806 by tommylight
Not glad about it, but welcome to the club !
I have a Mazak that has something that i can only describe as "reversed resolvers" that i have to replace with encoders, and since i gave the small lathe to a "friend" i have to go to another frined to make the new shafts.
Regards,
Tom, the "not helping guy" :)
The following user(s) said Thank You: RotarySMP

Please Log in or Create an account to join the conversation.

More
23 Feb 2021 09:21 #199807 by RotarySMP
Adding encoders to the existing motors is also an option, I need to work through.

Please Log in or Create an account to join the conversation.

More
23 Feb 2021 10:04 - 23 Feb 2021 10:41 #199810 by anfänger
What resolution do you need for the encoders?
There is one converter with an nicrosontroller in the wiki:

wiki.linuxcnc.org/cgi-bin/wiki.pl?ResolverToQuadratureConverter

With this you could move to a simple retrofit with keeping the drivers and just switch the control. Cause everting look really nice and neatly organised.
Last edit: 23 Feb 2021 10:41 by anfänger.

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 02:16 #200366 by andypugh

anfänger wrote: What resolution do you need for the encoders?
There is one converter with an nicrosontroller in the wiki:

wiki.linuxcnc.org/cgi-bin/wiki.pl?ResolverToQuadratureConverter


That never really worked.
Certainly not up to the standard that you would want on a Schaublin.

I ended up using a 7i49 instead.
The following user(s) said Thank You: anfänger

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 08:58 - 28 Feb 2021 09:00 #200380 by db1981
Replied by db1981 on topic Schaublin 125-CNC retrofit.
Hi Mark,

i have took a quick look at the 7i49 manual. From the hardware layout (Ananlog INs and Outs ) it should be capable to interface Synchros.
But for this a firmware mod is needed. don't know if this card has an own subprocessor FPGA/DSP or everthing is done by the mesa master card. if the hardware site fits moding the detection in vhdl should be no big problem.
https://www.researchgate.net/publication/287582285_A_new_FPGA_prototype_for_synchro_to_digital_converter_using_CORDIC_algorithm

i have no overview of the hostmod firmware, because i haven't need it before.

Maybe PCW could tell if this would be a time consumption task or an ten-liner....
Last edit: 28 Feb 2021 09:00 by db1981.

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 09:29 #200382 by Muzzer
Replied by Muzzer on topic Schaublin 125-CNC retrofit.
You could simply replace the synchro resolvers with a conventional encoder and drive the motors with a DC servo drive. I have the cncdrive DG4S servo drivers in my 1983 Shizuoka mill . They work fine with the SEM brushed motors and Heidenhain clone encoders originally fitted. The original tachos are no longer required with modern digital drivers, but I left those where they were due to the way they are fitted within the motors.

The original controller in the Shizuoka drove analogue servo amplifiers and DC brushed motors but the Micon control software dealt in digital units of course. So the initial output from the controller was step/dir, with a "positioner" module to compare that with the encoder feedback and generate an analogue (+/-10V) signal for the amps. So step/dir interfaces in analogue servo systems are not unheard of.

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 12:46 #200399 by andypugh

db1981 wrote: i have took a quick look at the 7i49 manual. From the hardware layout (Ananlog INs and Outs ) it should be capable to interface Synchros.


I am using a 7 wire Synchro Resolver with a 7i49 as the spindle position feedback on my lathe. That has 4 primary coils and a centre-tapped secondary. I managed to get it to work but can't remember the details.

I think that the STMBL hardware is capable of driving a DC servo. And it works with conventional resolvers, so might be capable of doing what you need with only a minor software rewrite.

Of course the really cool solution would be to port LinuxCNC to the Data General Nova.

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 13:06 #200401 by RotarySMP

Of course the really cool solution would be to port LinuxCNC to the Data General Nova.


LMAO :) That would be a serious port. Stuff Linux into 16kb !

Here is the latest video:


I am going to be seriously short of space once I cram everything into the pneumatics space. AC servors direct use of single phase is another advatage, so I wont need transformers. I am tending towards AC servos interfaced with analog +/-10V, so I can use a 7i97 and add linear encoders.
Mark
The following user(s) said Thank You: arvidb, Clive S, J Green, Aciera

Please Log in or Create an account to join the conversation.

More
28 Feb 2021 13:22 #200407 by db1981
Replied by db1981 on topic Schaublin 125-CNC retrofit.

LMAO :) That would be a serious port. Stuff Linux into 16kb !


That's stuff for an "old rabbit" :-)

in 1997 i coded an complete FAT32 file system / atapi and ide managment in an ATMega with 4Kb .... to play mp3 through an texas 320 dsp.
mempage switching due that you only had an 8 bit data bus, write own mem compression routine because of minimal ram .....

most of todays guys sadyl code memory waste from morning till evening ....
The following user(s) said Thank You: Mike_Eitel

Please Log in or Create an account to join the conversation.

Moderators: piasdom
Time to create page: 0.159 seconds
Powered by Kunena Forum