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General Mach Discussion / Re: programming novice (and I mean NOVICE)
« on: November 28, 2016, 05:03:21 AM »
Hi Rob
Many thanks for looking i at this I will try to explain further:
The job is to overlay weld material inside a pipe. Basically the pipe is held in a very large rotating chuck. This rotator is a separate machine and requires a start stop signal to operate and will give a movement signal in the form of a tacho signal which we need to count the tacho pulses to ascertain the pipe position. I intend to count the number of pulses it takes to do 1 full 360 deg rotation and then we can use this figure to calculate the overlap of weld on each rotation. The weld process is to be as continuous as possible (the problem will be the tungsten point erosion which is why we need the ability to change the tungsten from time to time). So the welding head is mounted on a long arm (X axis) which goes inside the pipe (4.5M long) and starts welding at one end and works its way back to the open end where the arm went in, this is the step over after each 360 deg + some overlap say 1 or 2 deg (this needs to be tested and could possibly do with being made an input variable) the x axis will move 3mm to 10mm dependent on weld procedure hence why the step over distance has to be a variable input by the user. The torch mounting will have 2 axis which are motorised and moved via a joystick, it is only a small amount of movement say 60 mm up and down and 50 mm left and right. These will be the Y and Z axis Z being up and down.
The jogging movement will require x,y,z
The crash detect is only required for the manual movement into the pipe (some pipes will have an end cap so we don't want the operator to crash the torch head)
The torch height and left right position have to be manual controlled - unfortunately and torch height THC is not possible because there are 2 independent voltages being used in the weld pool and this confuses the hell out of THC systems. The weld head will have a camera system which the operate will use to monitor the torch height - but in theory once the machine is welding this height shouldn't really need to change because the pipe is perfectly centered.
So the output procedure is quite critical in order of operation, i.e Starting the welding machine will initiate the main arc this needs a time to establish (around 1 to 2 sec) the arc initiated signal would have be present on input 2 before the establish delay. If input 2 is not present the machine must display a NO START error on screen and the user will then restart the process. Then the wire feed needs to start and then following another 1 sec delay the rotation needs to start hence the output 3.
The input 4 was a typo my error sorry for the confusion. Input 2 is the arc monitor and must be present at all times for the operation to continue, if at any point this signal is not present the machine must ALL STOP.
With regard to ALL STOP using the e stop does this mean the operator can restart from where the weld left off? - he may have to reverse the rotation a little bit but this will be controlled via a completely separate system controller so we don't need to worry about it in the program here. The important thing is that the weld can be restarted after an all stop, but there may be a requirement to change the tungsten so the machine would have t know where it stopped and still monitor the tacho feed for the rotational value.
The machine operation is a mixture of manual and automatic process. The weld part is the automatic bit this needs to have a button on screen that the user presses when the torch is positioned at the start of the pipe, the program will then control all the weld operations which is basically described above as the starting order of what is effectively 4 separate entities:
1 welder
2 wire feeder
3 rotator
4 x axis control (this is the g code controlled bit and the complex bit is being able to stop the process and move the x axis to a home position outside the long pipe, change the consumables and then send it back into the pipe to the exact poss ion that it left at)
I hope i have explained a little better this time. If you would like to talk to me about this (and I think if you are going to help me that would be a good idea) then my phone number is 07785 750660, or let me have yours and I can contact you.
Very kind of you to take the time you have on this and like I have mentioned before I don't expect you to do anything for nothing.
I have re done the process list below and hope this one is a bit clearer.
Manually drive to start point and set as ZERO. Proximity sensor for crash detect stop all movement ensure manual override cannot drive forward only dive away from proximity sensor. (INPUT 1)
Determine STEP OVER (step over is a movement of the X axis) and enter (+ or - for direction user to enter into a dialog box on screen)
Set TORCH HEIGHT (user to manually position using joystick control)
START weld starts (OUTPUT 1), receive signal WELD ON (INPUT 2) then 1 sec delay wire filler feed starts (OUTPUT 3) 1 sec delay rotation starts (OUTPUT 2),
360 deg rotation, signal step over (INPUT 3) (rotation signal provided by a tacho encoder)
Move step over distance (all weld and rotate signals remain on)
If weld on signal not present (INPUT 2) ALL STOP
If ALLSTOP(button on screen and possibly stop button on control panel (INPUT 5) or if arc detect signal is lost. Immediate – stop feed - stop weld – stop rotation, lift torch to home position. Remember x axis position. Operator to decide what action to take.
1) restart weld procedure
2) extract torch and then send back to where it stopped and restart
operator must be able to manually adjust x,y,z axis using joysticks or onscreen buttons.
If TUNGSTEN CHANGE button on screen - continue weld to step point. Stop rotation Stop wire feed Stop weld wait for slope out approx 4 seconds.
Lift torch to home (home for Z axis will be fully up position just to make sure torch clears the pipe surface)
Remember X axis position. Return X axis to home (please note this is the extracted position not the very first weld position)
Operator changes consumables. Press RESUME X AXIS button on screen
X axis returns to last stop point +/- step over distance (very important). Set TORCH HEIGHT (manual operation using joystick). Press WELD RESUME button on screen- START continue with weld procedure
Whilst job is running
Manual adjustment made by operator on Z and Y axis by joystick this is torch height and position left/right
parts purchased so far
http://www.ebay.co.uk/itm/182039059876?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
http://www.ebay.co.uk/itm/121684677476?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
plus two smaller motors NEMA17 for the Z and Y axis controller complete with controller http://www.ebay.co.uk/itm/251117211299
Many thanks for looking i at this I will try to explain further:
The job is to overlay weld material inside a pipe. Basically the pipe is held in a very large rotating chuck. This rotator is a separate machine and requires a start stop signal to operate and will give a movement signal in the form of a tacho signal which we need to count the tacho pulses to ascertain the pipe position. I intend to count the number of pulses it takes to do 1 full 360 deg rotation and then we can use this figure to calculate the overlap of weld on each rotation. The weld process is to be as continuous as possible (the problem will be the tungsten point erosion which is why we need the ability to change the tungsten from time to time). So the welding head is mounted on a long arm (X axis) which goes inside the pipe (4.5M long) and starts welding at one end and works its way back to the open end where the arm went in, this is the step over after each 360 deg + some overlap say 1 or 2 deg (this needs to be tested and could possibly do with being made an input variable) the x axis will move 3mm to 10mm dependent on weld procedure hence why the step over distance has to be a variable input by the user. The torch mounting will have 2 axis which are motorised and moved via a joystick, it is only a small amount of movement say 60 mm up and down and 50 mm left and right. These will be the Y and Z axis Z being up and down.
The jogging movement will require x,y,z
The crash detect is only required for the manual movement into the pipe (some pipes will have an end cap so we don't want the operator to crash the torch head)
The torch height and left right position have to be manual controlled - unfortunately and torch height THC is not possible because there are 2 independent voltages being used in the weld pool and this confuses the hell out of THC systems. The weld head will have a camera system which the operate will use to monitor the torch height - but in theory once the machine is welding this height shouldn't really need to change because the pipe is perfectly centered.
So the output procedure is quite critical in order of operation, i.e Starting the welding machine will initiate the main arc this needs a time to establish (around 1 to 2 sec) the arc initiated signal would have be present on input 2 before the establish delay. If input 2 is not present the machine must display a NO START error on screen and the user will then restart the process. Then the wire feed needs to start and then following another 1 sec delay the rotation needs to start hence the output 3.
The input 4 was a typo my error sorry for the confusion. Input 2 is the arc monitor and must be present at all times for the operation to continue, if at any point this signal is not present the machine must ALL STOP.
With regard to ALL STOP using the e stop does this mean the operator can restart from where the weld left off? - he may have to reverse the rotation a little bit but this will be controlled via a completely separate system controller so we don't need to worry about it in the program here. The important thing is that the weld can be restarted after an all stop, but there may be a requirement to change the tungsten so the machine would have t know where it stopped and still monitor the tacho feed for the rotational value.
The machine operation is a mixture of manual and automatic process. The weld part is the automatic bit this needs to have a button on screen that the user presses when the torch is positioned at the start of the pipe, the program will then control all the weld operations which is basically described above as the starting order of what is effectively 4 separate entities:
1 welder
2 wire feeder
3 rotator
4 x axis control (this is the g code controlled bit and the complex bit is being able to stop the process and move the x axis to a home position outside the long pipe, change the consumables and then send it back into the pipe to the exact poss ion that it left at)
I hope i have explained a little better this time. If you would like to talk to me about this (and I think if you are going to help me that would be a good idea) then my phone number is 07785 750660, or let me have yours and I can contact you.
Very kind of you to take the time you have on this and like I have mentioned before I don't expect you to do anything for nothing.
I have re done the process list below and hope this one is a bit clearer.
Manually drive to start point and set as ZERO. Proximity sensor for crash detect stop all movement ensure manual override cannot drive forward only dive away from proximity sensor. (INPUT 1)
Determine STEP OVER (step over is a movement of the X axis) and enter (+ or - for direction user to enter into a dialog box on screen)
Set TORCH HEIGHT (user to manually position using joystick control)
START weld starts (OUTPUT 1), receive signal WELD ON (INPUT 2) then 1 sec delay wire filler feed starts (OUTPUT 3) 1 sec delay rotation starts (OUTPUT 2),
360 deg rotation, signal step over (INPUT 3) (rotation signal provided by a tacho encoder)
Move step over distance (all weld and rotate signals remain on)
If weld on signal not present (INPUT 2) ALL STOP
If ALLSTOP(button on screen and possibly stop button on control panel (INPUT 5) or if arc detect signal is lost. Immediate – stop feed - stop weld – stop rotation, lift torch to home position. Remember x axis position. Operator to decide what action to take.
1) restart weld procedure
2) extract torch and then send back to where it stopped and restart
operator must be able to manually adjust x,y,z axis using joysticks or onscreen buttons.
If TUNGSTEN CHANGE button on screen - continue weld to step point. Stop rotation Stop wire feed Stop weld wait for slope out approx 4 seconds.
Lift torch to home (home for Z axis will be fully up position just to make sure torch clears the pipe surface)
Remember X axis position. Return X axis to home (please note this is the extracted position not the very first weld position)
Operator changes consumables. Press RESUME X AXIS button on screen
X axis returns to last stop point +/- step over distance (very important). Set TORCH HEIGHT (manual operation using joystick). Press WELD RESUME button on screen- START continue with weld procedure
Whilst job is running
Manual adjustment made by operator on Z and Y axis by joystick this is torch height and position left/right
parts purchased so far
http://www.ebay.co.uk/itm/182039059876?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
http://www.ebay.co.uk/itm/121684677476?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
plus two smaller motors NEMA17 for the Z and Y axis controller complete with controller http://www.ebay.co.uk/itm/251117211299