Help needed on the best way to control a 8 position lathe turret

[jumps4]

You currently are using the 1 Output only Turret PLC, it is designed for a turret that only moves in 1 direction, which is suppose to be connected to Output 2. Having it connected to Output 1 is going to cause the turret to spin, as Output 1 "NoFaultOut" will stay on (Green) for as long as the control is not in fault.

Your inputs 1234 and 7 have a line over them, as you may have Inverted those inputs. You can do this by pressing ctrl-alt-I on any input to invert the input.

Chris
Do i need to take the inversion off those inputs
I'm not sure what inverted means
Steve

[martyscncgarage]

Thanks Marty
I don't hurry
as in the title I'm looking for the best way not just what may suffice
I might fail but not without a struggle, so that's OK with me.
Steve

It won't fail...you'll get there!

[jumps4]

I have been working on replacing all of the electronics for the gray logic sensors on the turret.
Everything has now been replaced by this encoder wired directly into Acorn inputs 1234.
Thank You for viewing
Steve
A Video and a few pics:
https://www.youtube.com/watch?v=7e66hcB ... e=youtu.be

[jumps4]

I have been testing the encoder for a while and I really like it.
My electronics would return all input states to low when not on a tool position.
This encoder stays on the previous tool number the entire time until it reaches the next tool. This allows for 4 low inputs to be counted as a tool
number .
By working this way it can also be used for 16 tools. With a life expectancy of 25,000 rotations.
Steve

[jumps4]

Today I made good progress.
gray logic 2 output would not do anything it locks up cnc12 and you cannot get to mdi. All you can do is exit.
but after installing gray logic 1 output the turret runs and changes tools as it should.
Now if I can get some help with a little code work.
the program is supposed to be using only one output but it is using 2 . relay 1 comes on as soon as cnc12 starts, I have no idea why but it is not being used by me at the moment.
I would like relay one to reverse to lock the turret If someone could help.
If I could set a time to reverse on relay one after it has reached the position, just like it is supposed to in the gray logic 2 output, then I can lock the turret.
here is a video and a report
Thank You
Steve

https://www.youtube.com/watch?v=7P9ODEB ... e=youtu.be

report_38D2697CA033-0611180974_2019-10-03_14-27-57.zip

(374.11 KiB) Downloaded 120 times

[thermo44]

This post is awesome, I just bought an Acorn and I do use arduino, so I'm pretty excited about what you have wrote. Once I connect my acorn to my mill, I will try to upload all the info that I can and ask if I may, a few questions, but so far, you deserve a big hug! Cheers!!

I left one detail out in my previous post. Somehow the external logic needs to know which tool position is desired. Unfortunately, that uses I/O. Two bits can define up to four positions. Three bits can define up to eight positions

Tool Positions using three output signals
000 = 0 No Tool
001 = 1 Tool 1
010 = 2 Tool 2
011 = 3 Tool 3
100 = 4 Tool 4
101 = 5 Tool 5
110 = 6 Tool 6
111 = 7 Tool 7

Tool change required output
0 = No change required
1 = Change tool

Tool change state input
0 = Tool change completed
1 = Tool change in progress

So, you would set the tool desired by changing the three outputs that define which tool to use. Then you would turn on the change tool output. When the outside logic saw the tool change command, it would set the tool change state output to 1. That would signal the Acorn to turn off the tool change command and to wait until the input bit was turned off before continuing. The outside logic would move the turret until the desired tool was in position and then it would turn off its tool change output to signal to the Acorn that the positioning was complete.

To recap: Six positions on the turret would require 4 output signals from the Acorn, 1 to command a tool change and three to define which tool to use. One input on the Acorn would monitor the status of the tool change operation.

If four outputs are not available, then you could "bit bang" an outside logic device by using two outputs. One output would serve as a data line and one output would serve as a clock line. The data line would be set high (on) and the clock line would be toggled On then Off three times to signal that a tool change command was coming. The Acorn would use the table above so that bit 0 is the least significant bit in the table above and bit 2 is the most significant bit in the table. The Acorn would set the data line to the value of bit 0 and toggle the clock line On then Off. The Acorn would set the data line to the value of bit 1 and toggle the clock line On then Off. The Acorn would set the data line to the value of bit 2 and toggle the clock line On then Off.

Bit banging is more complicated, but it would allow you to use more tools without using up all of the output lines.

[jumps4]

THE encoders i bought are junk.
I put a degree wheel on the turret after noticing the tools looked off
It got 0,44,92,131,177,222,270,313,360.
My tool heights are all over the place.....
Aarrrrgggg
Steve

[martyscncgarage]

THE encoders i bought are junk.
I put a degree wheel on the turret after noticing the tools looked off
It got 0,44,92,131,177,222,270,313,360.
My tool heights are all over the place.....
Aarrrrgggg
Steve

That was that inexpesive Gray logic encoder you bought?
How about making it an axis driven tool changer? Use a closed loop hybrid stepper motor.
Just a thought.....

Marty

[jumps4]

I'm going to just stare at if for a while...
I don't like to loose when it's not my fault.
I haven't found anyone to help me change the 1 output code to reverse yet so i ordered a reversing relay timer. The 1 output code works perfect if I had a dc motor and used the type of relay in the wiring diagram.
If i can't change the code to fit my needs I'll add more electronics and a real encoder.
It has become a challenge now.
Steve

[jumps4]

Another Idea:
I have noticed that my lathe tools are not all holding the cutting edge of the inserts at .500 over the base of the tool. This was going to be addressed by finding the highest tool and shimming the others to match when mounting.
I'm now hashing a plan to save the tool positions as way points and naming the way point the tool number. By doing it that way i can set the tool height for each tool with a height gauge. By using a Arduino and a 8000 pulse per rev encoder I should be able to assign a tool number to a saved location. Arduino would then return the proper gray logic code to Acorn for the requested tool and lock the sprag clutch. Arduino does not need to know tool number requested, Acorn is stopping the motor when it see's the location it wants. When the motor forward rotation is stopped, Arduino reverses the turret to lock.
This seems like a really good idea and the Acorn gray 1 output code i have now won't need to be modified. Changing Acorn looks a lot harder than learning Arduino. I will even be able to set tool height automatically by tool touch off.
All my problems I'm having could in the end produce better results and ease of use.
OK only one problem left, I have to learn how to write Arduino code.
Steve