"Smart" Multipex Tattoo Power Supply Project.

Hello Arduino Community! My friend, and I want to make a device that outputs to 4 different tattoo machines. We wanted each to be able to be set to different voltages and have the output voltage displayed. We also wanted to switch between the machines easy and conducive to the tattoo artist. Like having ink or other pathogens on when operating and being able to cover and/or sanitize the buttons or knobs or whatever "human interface" we went with.

After some research I had an analog circuit drawn up and ready to have the different modules printed up. When I found out how expensive it was to print out proto boards I had someone comment that everything already made and mass produced will always be the cheaper way to go. So I started looking into that and found many pre made modules that would fit the bill, as I kept looking into it they kept saying "compatible with arduino", so I googled it...
Blew my mind! So I went out to my nearest electronics shop and bought a starter kit. Blew threw all the example sketches, started modifying the code, put them together, and then wrote my own to start fitting into what I wanted to get done.

I haven't gotten very far to say the least... But, it's a learning process and at least there is progress on that front. I read forums and blogs and watch videos every day whenever I have some spare time.
But I'm sticking to it because I see how powerful this little thing can be if I can just tap into its true potential.

So, what I thought about doing is getting his "Tattoo Machine Power Supply"(that I will call TMPS for short from now on), turning it all the way up, sticking a shorted out MONO plug into the foot pedal socket and interfacing with it using an arduino. What do you guys think? Then I could do some really cool stuff like adding batteries so he can go wireless for a while, adding a wireless footpedal, smart lighting, emergency "bump" alarm, clock/timer, smart cooling fan, capasitive touch or touchscreen interface covered with glass to easily disinfect, completely get rid of knobs and selector dials, and so on...

So far I got a relay that runs the fan to go on and off with a temp sensor that I mocked up with a POT(actual sensor and fan on the way). I've also installed a KA05 shield made by velleman. It is an i/o shield, it has six relays that take up pins 8-13 and pins 2-7 has pull up resistors with leds on them as well as pins A0-A5.

I thought it was a good place to start. relay six will be for the fan and relay 5 I was going to use to switch the power to the TMPS on and off. Got that part working as well. But I found out about "SLEEP_MODE" and I've been trying to figure that one out. I have a topic about that going already. You can check it out here: Sleep Mode for Newbies? - Programming Questions - Arduino Forum

I"m planing on using a capasitive touch sensor for every button, I found one on ebay that is backlit and you can put behind thin glass.

http://www.ebay.com/itm/3pcs-lot-HTDS-SCR-Capacitive-Touch-Switch-Button-Module-Anti-interference-/162193195741?hash=item25c377c2dd:g:V1gAAOSwgmJXzmNp

I'm going to use a button for each channel or output. so that shouldn't be to hard to program but I still haven't been able to get only one to turn on at a time. Then I started to think about how I was going to control the voltage with touch buttons too, I haven't found a definitive answer yet but I have one option now. I have another topic going for that here: How to replace a potentiometer - General Electronics - Arduino Forum

Then I thought I could write something for a "BUMP" alarm. Basicaly, all of this is going to be housed on a cart that he already uses to house his power supply and a surgical tray that he sets his inks and machines on. So I thought I would add a speaker or something and a gyroscope and if someone accidentally bumps into the tray an alarm will go off and whatever tattoo machine was on would shut off until the alarm was reset by a push of a button.

Next big task I think will be trying to set up an i2c "pin extender". I realized that if I have an on/off button, "-"/"+" button for the voltage for each channel, and a selector button for each channel, Im at around 13 buttons, so I ordered this:http://www.ebay.com/itm/351608126297?_trksid=p2060353.m2749.l2648&ssPageName=STRK%3AMEBIDX%3AIT
When it comes in I will start to tackle that subject.

It would be cool to eventually add Bluetooth to it so they can control it from a phone as well.

Then I realized that the arduino isn't very good at keeping time so I'm going to have to figure that out after I figure a few more things I already have going on out first. But, I would like to be able to display the time clearly and with a timer on it, because they charge by the hour sometimes, or have other clients coming in at a certain time.

My friend also mentioned to me how it would be cool if I could add a touchscreen to interface with for all the other features like the timer, dialing in amperage or checking internal temps or even display ambient temp. It can also display battery levels, operating time left, and even a low battery reminder and alarm. But that is so beyond my level that I don't even know where to start.

I still haven't actually figured out all the power stuff out yet either. I'm going to need 5v to power the arduino and relays, 12v for the bigger relays and fan, 24v for the TMPS, and make all a UPS (uninterruptible power supply) controlled by the arduino so you can turn it on and off but still keep power just to the arduino to hold the voltage settings for the different channels.

Then there is the whole foot pedal that I have to figure out. We want it to be versatile, have options. To use it wired or wireless, or a different foo tpedal all together. I thought I could use a separate arduino all together like a lillypad or something tiny like that and Bluetooth that can talk to the main one and control a relay that switches the tattoo machine on and off. maybe I can connect that same relay circuit to a cable that will connect the two physically and charge the on-board battery of the tiny one.

Ok, I think that's enough ideas from me for the moment. I would like to hear what you guys think, how I should go about this? Do you think that I will be able to achieve all of my goals with the arduino uno?

I could also use all the help I can get on sketches and coding as well as ideas on circuits and shields and stuf thats out there. I haven't found anybody that has done what I am trying to do so finding info on some stuff has been difficult. Sorry if I rambled on or made this to long, I was just trying to be thorough and informative. I wil try to keep everyone updated on my progress.

That is certainly one long requirements statement. Can you draw a schematic (by hand would do) showing the major components and their interconnection and post a picture of it? It may then be easier for everyone to visualize.

TheMunkee:
After some research I had an analog circuit drawn up and ready to have the different modules printed up. When I found out how expensive it was to print out proto boards I had someone comment that everything already made and mass produced will always be the cheaper way to go.

Have you looked into hobbyist prototyping serviced like OSHpark.com? Two-layer boards are $5 per square inch (with 3 copies of your board included in that price) and ship in under 12 calendar days from ordering.

I did not know of that websites existence! Thank you for introducing it to me! I will look into it a little more but will probably use them for some of my stuff. That definitely the kinda help I can use.

6v6gt:
That is certainly one long requirements statement. Can you draw a schematic (by hand would do) showing the major components and their interconnection and post a picture of it? It may then be easier for everyone to visualize.

I haven' drawn out all the components out yet. But I will share what I have and will draw out the rest the best I can when I have the time.

Here is the output module I'm going with.
I also had the analog "dial" module circuit that I was trying to replace but I can't find it right now.

I'm sorry about that guys! I posted the wrong picture. Here is the schematic, might make more sense...

I'm attaching the schematic I was given in another thread here. It allows me to take a high voltage of about 24v and step it all the way down to about 1.5v with a PWM signal. At least that's what I understand. I still don't know how to write the code for it... lol But the hardware is half the battle right... :frowning:

:o Sorry! Forgot to attach!

You can use this Kit as a basic of the power supply, it is cheap platform.
0-28V 0.01-2A Adjustable DC Regulated Power Supply DIY Kit

http://tuxgraphics.org/electronics/201005/bench-power-supply-v3.shtml

Thank you! That is going to be extremely helpful! Lots of info to digest.

I drew out most of my idea. It's a little sloppy with a few mistakes, but I think you'll get the idea. Only thing is, It won't let me post it....