Touch sensor Box Mod

[MonkeyTokes]

I'm working on a new box mod and wanted to try something a bit different. Instead of having a master switch or button to allow switch two to fire the mod I was thinking maybe a touch sensor or something similar placed in one of the sides. I've come across arduino touch modules for super cheap but I have no experience with these. Does anybody have ant idea If they'd work or of some other sensor that could work?

 

[Zanderist]

I have done a non v aping related experiment with a touch sensor, and from what I can remember is that it does work. I used a single mosfet to accomplish this.

The problem faced by this is that if you hands are very moist as in lightly sweaty and you touch the sensor you risk having some moisture deposited which will keep the unit firing.

So I'd say give a go but figure out how to make it safe.

 

[Visus]

Zander check out the ego touch board
on ft its capacitive so wet hands won't missile it. wire it to nfet good to go with on off etc... really cool how those ego boards can monitor and function our mods.

 

[Zanderist]

Are you talking about something like this?
https://www.youtube.com/watch?v=TFo2Wy5yDtA

See when I here people talk about touch switches in mods I instantly think to the experiment in one of radio shacks electronics kits.

Now for that to have a fail safe maybe design it with AND logic, as in you need to have more than one finger touching across copper or any conductive metal plates to turn in on. How I see it

+V----(||)------(||)------Gate Pin

 

[Visus]

Ya thats the one, the evod touch its a capacitive switch so moisture doesn't affect it like issues with fets; if wet it makes it harder to fire just like our smart phones, so no misfires because of..

ya a bridgeable conductor will misfire if wet or e juice on fingers and ya gotta dial it in...

$3.96 eVod 3.7V E-Cigarette Battery Touch Control Module (3-Pack) 3-pack at FastTech - Worldwide Free Shipping

 

[tehdarkaura]

capacitive touch sensors are affected by water and moisture... just like our phones since that is what they use...

Atmel is the company that produces the best touch sensors, and its also the company who produces the AVR's that power the arduinos so most AVR's have this functionality in them.

you can likely find a dedicated atmel touch sensor that will be tiny if you just need a simple touch -- its not super complicated -- power the chip run a line to the "sensor" plate and run a line to your power control,

you could get really fancy and add a slider or rotary type touch sensor then it might make it worth getting a tiny arduino like the arduino pro mini to power that logic. but this is complicated and you will likely get best results using the atmel IDE instead of the arduino IDE.if you do decide to do so. so unless you know C or ASM this isn't really an option also the fancier touch sensors require a special copper pcb with to be made with you button patterns. a simple touch sensor typically has this built in or will work when attached to a small piece of double sidded pcb thats isolated from everything else and has a non-metalic path to your finger.

 

[DrBeaker]

I did a thread on the adafruit touch switch. I got it to work with an sx-350. I posted pictures and how to wire it up....

 

[MonkeyTokes]

Ya thats the one, the evod touch its a capacitive switch so moisture doesn't affect it like issues with fets; if wet it makes it harder to fire just like our smart phones, so no misfires because of..

ya a bridgeable conductor will misfire if wet or e juice on fingers and ya gotta dial it in...

$3.96 eVod 3.7V E-Cigarette Battery Touch Control Module (3-Pack) 3-pack at FastTech - Worldwide Free Shipping

Put these on my last order along with some conductive pads for video game buttons.

 

[MonkeyTokes]

I did a thread on the adafruit touch switch. I got it to work with an sx-350. I posted pictures and how to wire it up....

Awesome!! I'll definitely check it out!

 

[MonkeyTokes]

capacitive touch sensors are affected by water and moisture... just like our phones since that is what they use...

Atmel is the company that produces the best touch sensors, and its also the company who produces the AVR's that power the arduinos so most AVR's have this functionality in them.

you can likely find a dedicated atmel touch sensor that will be tiny if you just need a simple touch -- its not super complicated -- power the chip run a line to the "sensor" plate and run a line to your power control,

you could get really fancy and add a slider or rotary type touch sensor then it might make it worth getting a tiny arduino like the arduino pro mini to power that logic. but this is complicated and you will likely get best results using the atmel IDE instead of the arduino IDE.if you do decide to do so. so unless you know C or ASM this isn't really an option also the fancier touch sensors require a special copper pcb with to be made with you button patterns. a simple touch sensor typically has this built in or will work when attached to a small piece of double sidded pcb thats isolated from everything else and has a non-metalic path to your finger.

Doesn't sound as complicated as I'd expected really. It seems like the hard part will be finding a way to install and conceal it neatly since it will have to be mounted outside of the box since most all premade touch sensors I've found have components on both sides of the PCB making it mostly impossible to mount it inside the box with a hole for the touch sensor which was my initial idea. Though I'm thinking maybe something like the Dimitri box mod with a copper plate on the side under the fire button or the reverse side would look snazzy and function properly. I suppose I should start getting myself acquainted with these little atmel guys.

BTW I have a basic grasp of c++, lua and java so I guess I should be alright in that respect. We'll see where I end up, right now I'm just getting a bit of everything to test and see what will work best!

 

[DrBeaker]

The adafruit touch switch is fairly flat and you can put it anywhere in your box and use a wire and a target on the outside of the box. I found in my testing that if you licked the actual board it would keep closed until you dried it off. But if you use a wire and a target that didn't happen. There is a place on the board to solder a wire for remote target fireing. I used a brass paper fastener. The only reason I didn't implement it into my mods id the fact that my bodys are made of carbon fiber and any part of the contact plat or wire would cause it to fire. I am sure there must be a way to insulate it so that doesn't happen but I don't have time to figure it out.

 

[tehdarkaura]

I can't say that I've ever used a carbon fiber housing with a touch sensor but from what I can find its behaves a lot like metal -- so you can not sense capacitance through the material

but taking carbon fiber out of the equation you can make it a narrower point of activation by using double sided pcb and have the bottom ground plane much larger than the top sensor plane. it will also make it a bit less sensitive in all when you do this. length and path of wires to these types of sensors are important too. Atmel has a document describing "QTouch" that you might want to check out -- give a bunch of example buttons and things to watch out.

They also have a table of permittivity -- but it only covers types of plastics and glass , I don't remember carbon fiber being described...

 

[MonkeyTokes]

I finally got the evod touch PCB the other day but I'm kind of having a problem. Because this isn't just the touch module its the entire control of the evod device it has the 10 second cut off, etc. Its not just a switch. So how would I wire this into a MOSFET box mod so this is just working as a switch in line with the fire switch, basically like the and gate previously mentioned. This switch, and the fire button have to be pressed simultaneously to fire instead of having a master switch. It seems simple in theory but these evod devices this is made for can't go below something like .8-1.2ohms so it won't fire my devices, plus I feel like its going to burn out if I do it wrong and wire it along side the mosfet because then much higher amps and wattage will be pulled through the device than it is made to handle. Any ideas? I know this threads old so I mat just start a new one but the people who answered seem to have a ton of knowledge on the topic.

For the record the wiring is as follows;
Black-Battery negative and has a piece of the coating in the center missing to splice to the 510 negative.
Red - battery positive
Yellow - 510 positive
Blue - touch switch

 

[ayopassthat]

Join Box Modders on Facebook and search "touch switch" - one of the admins outlines how to do it with two MOSFETs. Here is the diagram.

https://fbcdn-photos-f-a.akamaihd.n..._=1437604074_2fc896e53f6043e46b9478b02f4881bc

 

[DrBeaker]

Well
This type of touch switch can be used to pull a + to a ground or a - to + if you wire a biased transistor up to it.
Your right this thread is old and when I first wrote it it was fresh in my mind.. Now not so much. Either way your going to need a fair amount of electronic knowledge to pull it off. I don't know the evod method of firing? Does it do a pull down or pull up? That's the first thing...

I finally got the evod touch PCB the other day but I'm kind of having a problem. Because this isn't just the touch module its the entire control of the evod device it has the 10 second cut off, etc. Its not just a switch. So how would I wire this into a MOSFET box mod so this is just working as a switch in line with the fire switch, basically like the and gate previously mentioned. This switch, and the fire button have to be pressed simultaneously to fire instead of having a master switch. It seems simple in theory but these evod devices this is made for can't go below something like .8-1.2ohms so it won't fire my devices, plus I feel like its going to burn out if I do it wrong and wire it along side the mosfet because then much higher amps and wattage will be pulled through the device than it is made to handle. Any ideas? I know this threads old so I mat just start a new one but the people who answered seem to have a ton of knowledge on the topic.

For the record the wiring is as follows;
Black-Battery negative and has a piece of the coating in the center missing to splice to the 510 negative.
Red - battery positive
Yellow - 510 positive
Blue - touch switch

 

[mcclintock]

^^-- that should be simple -- may need a load resistor, could need to invert the signal to another transistor, but a MOSFET is easy to drive. The 10 sec cutoff is not something I'm a fan of in use, but is good for safety.

I had sent a PM about a sensor -- then realized it was a non-contact proximity type -- cool but unneeded. What would be the simplest would require hand contact to circuit ground, that is, the case. Simply a 10 Mohm pull-up resistor to the contact into comparators (need rail-to-rail input type, e.g. TLC2272 op-amp). Trigger on less than 1/2 power supply voltage. To improve, use a second comparator to look for very near ground, indicating it's shorted by metal not skin. Could require more to avoid noise on output (hard on MOSFET).

 

[MonkeyTokes]

Update:

I've finally had some time to work on this and will post a wiring diagram and photos of my 'prototype' in the coming days. Basically I've used an aluminum plate which I intend to either engrave or stamp with a logo and put on the side (sort of like a dimitri box) under the fire button. So when you grab the box at least one finger will be touching the pad essentually putting battery voltage through to the switches first terminal, then when you press the button it passes the voltage to the mosfet switching it on. Bingo! Exactly what i wanted, a touch master switch.

Unfortunately for simplicity I used the evod touch module so there is the 10 second cut off, but with my mods 10 seconds is too much anyway. The only down side to this is you need to remove your finger and replace it again to fire a second time. Obviously I will be using an actual touch module for the final but the evod touch has the touch capability and indicator LED that i needed, all wrapped up in a nice package.

 

[Visus]

That ego touch module also has on/off 5 clicks.. Wondering why two switches seems kewl setup tho..
No one would figure out how to fire esp if you 5 click it lol.. Win ya some good drinkin wagers at the bar lol..

 

[MonkeyTokes]

Oh yeah I forgot about the five clicks on and off. That's actually a bit of a pain, it seems like about one in four times you try and turn it on or off it doesn't work. Not a huge hassle for me but couldn't sell a mod with that. I kind of like it though that it can be completely shut off without a physical switch.

You could easily use this design to make a completely touch powered mod without the two contact points the other ones use, I just wanted to eliminate the need for a physical master switch so you don't need to pop the lid off to put it in your pocket or whatever. Also I'm not sure if its because the plate I'm using or if I'm supercharged but it activates the sensor even if you're finger is a few mm above it, including if some fabrics are between the plate and my skin. I'm one of those people that can't wear watches without them breaking so maybe I'm very conductive, or the aluminum threw off the calibration, not sure. Even as it stands, for me it's a lot better than one with two contact points.

 

[MonkeyTokes]

Here's a very simple wiring diagram. The evod modules are color coated, and the black and red wires are negative and positive of course. If you want to make it completely touch just omit the momentary switch and either connect the yellow wire directly to pin 1 on the mosfet or solder a 22ish gauge wire to pin 1 and connect the yellow wire to that wire since wires are incredibly thin and don't make for great wire to pin soldering.