Automated Welding Set Up

Hello All,

I am extremely new to the Arduino scene but I've been involved in a fabrication capacity with robotics and automation for some time. I have a project that I've been working on for a few months that i would like to automate to a certain degree. Below is a little information about the project.

Small Automated Welding Machine

The basic function of the machine will be to multiple settings (presumably set by a 12 position switch) that will control a large motor rotating on its Z axis that will turn a tabletop, a small DC motor (motor 2) rotating on its X axis that will turn a cam at a constant speed to oscillate a welding gun.

So I would think i would need the following parts: *DC Motor controller that could be controlled by Arduino for Motor 1 (speed and start/stop) *DC Motor controller that could be controlled by Arduino for Motor 2 (Speed and start/stop) *12 position switch that would select a certain setting (motor 1 speed) *A rotary encoder or some sort of sensor that will tell me how far my Table top has turned *A relay that will start the arc/gas flow on my welding machine (just a relay that i will cut inline on the trigger) *Start Button

I've written an outline of the sequence below

-Select setting on 12 position switch -Activate Start by depressing start button -The following would happen at the same time: Motor one start at pre-determined speed (Based on 12 position switch) and rotate for 360 degrees Motor two start and rotate at a constant speed until motor 1 reaches 360 degrees Relay for welding machine closes starting arc and stays closed until motor 1 reaches 360 degrees

The welding isn't critical here, but I do a lot of it. I'm not as interested today in writing all of the code as I am getting all of the correct parts so that when i do enlist some programming help, all of the pieces are correct, installed and working. I see a long process of setting up the proper rotation speeds on each, but once set, I think this will help me immensely.

Any help from the community would be great. Feel free to post questions and I will try and answer them timely. I may try and make a quick diagram later and post. I will also be posting the motor information for the large DC motor that i already have later today.

I'm currently working on a project that is similar to yours. but i'm running a drill press/mill instead of a welding gun. But that sounds fairly simple. how big of turntable are you turning? and roughly how much weight are you spinning?

is the welder at a fixed position? if so, are you welding a circle? or just tacking certain areas around a axis?

Could be rather difficult to get a standard dc motor to run to exact places as you say ( 360 degrees) even with encoders to track position.

As the motors are driving tables which may be heavy, there would I imagine be some acceleration and deceleration times required.

If you can overcome the above, then a "home" switch may be required so the program knows where each table is at the start and then rotate to a given point.

Relay for the "weld" would be whatever rating is required but the coil would need to be driven via a separate supply via a logic level mosfet or transistor ( perhaps a 2n7000 mosfet)

Any "speed and start and stop " would be written in the code. If using dc motor then pwm via logic level mosfet. Actually position is more of a stepper drive or servo drive arrangement. Speed set could be "selected" again by writing to a variable with a tactile switch and an LCD readout.

Rather large overall project to begin. Would suggest you do some simple basic motor speed /position exercises to begin with.

A welder will emit rather large amounts of noise which will interfere with any micro so look at that as well.