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Author Topic: WIRE LENGTH MEASURE AND CUTTER  (Read 3148 times)
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I don't think you connected the grounds, Dave.
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I have no idea if it will help you further, but if you want someone else to write the software, I'd suggest that is a better place.

Your call.
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Ok please do d needful.
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JIGNESH DHARIA

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Accuracy as you said 1% is ok.
How do you plan to measure the wire to that degree of accuracy?
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Thanks,
Accuracy 1% is OK.
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JIGNESH DHARIA

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Accuracy 1% is OK.
That wasn't the question. The question was how you intend to achieve that accuracy? Over what range of lengths? At what speed?
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Ok!
1)   Length range will be:
50mm to 20000mm
2)   Smaller the length more accuracy require and large length accuracy maximum should be 1%
3)   Speed I will consider Slow speed for small length, and little fast at large length.
4)   I require your assistance to select the speed respect to type of motor i.e. stepper or Servo.
5)   First manual feeder of wire till the tube end where we will keep sensor. Which control the length after every cut. Feeder motor work reverse to till the sensor (or tube end) and stop. The length of reverse will be manual feeding data respect to the distance of cutter edge from the (sensor) tube edge.
6)   On start feeder motor start feeding till the predefined length achieved and stop feeder motor.
7)   As soon as feeder motor stop cutter motor start to cut and returned to its open position once again for second cut.
smiley-cool   We put sensor to stop cutter motor.
9)   And again the new function will start (repeat the same cycle) till the pre-decided number of cut pieces of wire  require.
10)   One more sensor we will keep on starting of feeder tube to sense the wire is feed or not. If there is no wire or wire can over the entire process will stop. And start once wire will insert inside the tube.
11)   It will continue with the previous cycle if any cut is pending, once wire over from spool. Or we can reset for new cycle.
12)   **Cutter will start once feeder motor stop after feeding predefined length.
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JIGNESH DHARIA

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Ok!
On start feeder motor start feeding till the predefined length achieved
How will you know when the predefined length has been achieved?
How do you propose to measure how much has been fed out?
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Good Morning
1. How will you know when the predefined length has been achieved?
I will keep sensor near rear end of feeder tube. And co-ordinate with the programme.

The diameter of feeder roller is 50mm, In one revolution it will feed the wire is 50mm x 22/7=157.143mm.
Now we need to count revolution of the feeder roller require with respect to the length.

For example :- if I require to cut 100mm length then revolution will be 100mm/157.143=0.63636.
One revolution=360 deg.
One step = 1.8 deg
So one revolution has 200 steps of 1.8 deg each
Now I want 0.63636 revolution = 0.63636 x 200 = 127.27 steps.
In brief:-
To cut size L=100mm==Steps is 127.27 nearest steps will be 127
(if statement require or Rounded Off or Absolute value)

Total Number of Steps after which Feeder Motor Stops with respect to Length  is equal to

(( ( L / ((Diameter of feeder roller x 22)/7) ) * 200)

In this diameter of feeder roller is fixed i.e. 50mm.

2.How do you propose to measure how much has been fed out?
In this case We keep constant value i.e Distance between Cutter and Feeder Tube rear end.
I have made rough diagram, can I have your email ID so I can send you.
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JIGNESH DHARIA

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The diameter of feeder roller is 50mm, In one revolution it will feed the wire is 50mm x 22/7=157.143mm.
Assuming no slippage. Which is a lousy assumption.
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Which is a lousy assumption.

Which might be a lousy assumption. If it's a valid assumption in this environment then there's no problem using rotation of the rollers to determine the dispensed length, as long as it's calibrated correctly.
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Which might be a lousy assumption. If it's a valid assumption in this environment then there's no problem using rotation of the rollers to determine the dispensed length, as long as it's calibrated correctly.
Fair enough.
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The diameter of feeder roller is 50mm, In one revolution it will feed the wire is 50mm x 22/7=157.143mm.
Assuming no slippage. Which is a lousy assumption.
That was what I was getting at, but he could be using a pinch roller which would reduce (but not eliminate) the possibility of slippage. The other problem is with thinner, softer, wires tending to bend and 'bunch' in the feeder tube.
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INDIA
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Please give me code for measuring the length of wire. I will rectify with respect to my requirement. i HAVE ARDUINO uno AND A5020E SENSOR.
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JIGNESH DHARIA

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I would use a set of passive rollers to measure how much has been pulled out, with a separate set of drive rollers pulling the cable through the passive measuring rollers.

Do you really mean that you need better than 1% accuracy at 50mm? So 50.5mm or 49.5mm would not be close enough?
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I would use a set of passive rollers to measure how much has been pulled out, with a separate set of drive rollers pulling the cable through the passive measuring rollers.

Do you really mean that you need better than 1% accuracy at 50mm? So 50.5mm or 49.5mm would not be close enough?                        If possible for small size we require more accurate but for the size 10 mtr to 20 mtr 1% accuracy is perfect. If possible ......otherwise we work for 1%accuracy for all.
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JIGNESH DHARIA

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