IR frame or Touch-foil

broberg · Jan 8, 2018, 1:36 PM

@tomster I have looked at that before, but didn’t want to throw away the money if it didn’t work. How far up does the touch reach? And are you running it with the Raspberry Pi?

tomster · Jan 8, 2018, 2:05 PM

I had the same concerns regarding money-wasted, but once again curiosity beat reason ;-)

I am using a RasPi 3 and the bar works OOTB. The airbar will come calibrated for a 15.6" (laptop) screen. That is exactly the size of the available touch area.You might be able to see the dust marks on my screen. The bar will reach approx. up to the top of the news headline (“Des Politikers…”). There is a slight horizontal line I drew with my finger. The lateral limits are depicted by the 2 vertical lines on the airbar.
Regarding the mapping ratio, I hope the following is somewhat comprehensible:
With the standard configuration you will be able to use the whole touch area, but the mousepointer will be mapped to the full screen height. In my case that is 1920 pixels as I am using portrait mode.
So if I move the finger from the bottom to the upper touch area limit, the mouse pointer will actually move from the bottom of the screen all the way to the top. That way it is kinda impossible to accurately touch a virtual button on the screen. After some tweaking I found a setting that would map any input kinda 1:1 on the screen a.k.a. touch area.

Any other drawbacks?
Yep. Of course you will see fingerprints on the mirror from touching the surface. But since the bar is held in place by magnets it is quite easy to remove the bar and wipe the mirror with a cloth. Besides you will have to find a way to route the cable from the bar to the Pi. The cable is only about 20cm long…

tomster · Jan 8, 2018, 2:27 PM

Here’s a picture of my setup so far to illustrate how short the cable really is.
There are ventilation slats in my wooden case on top and also on the bottom. I routed the bar cable through one of the lower slits (marked in red). So the cable will be partionally visible.
I decided not to drill a whole in the mirror and disassemble the bar to get the cable “properly” routed through the glass because I was afraid to break the mirror while doing so.

I also found a SD card reader that will fit exactly the height of the ventilation slit. That way I will be able to replace the card without thee need of disassembling the whole mirror.
The loudspeakers will be connected to the Pi with a soundcard and a PAM8403 amplifier, because the screen’s speakers would not come out clear when hidden in the case and below the mirror.

cruunnerr · Jan 8, 2018, 5:06 PM

Maybe a silly question:

Does the Airbar sits under the Mirror glas or over that?

Different asking:
I my point of View it seems, that the Bar has to been installed “on the front”. So it has to been set on the mirror glas, right?
So i would be able to install it additional to my current Mirror?

tomster · Jan 8, 2018, 5:46 PM

The bar sits on top of the mirror and can thus be easily retrofit.
It comes with 2 small self-adhesive magnet plates that can be sticked directly onto the mirror.
I decided to drill 2 holes in the wooden frame and sunk 2 strong cylindric magnets (10x10mm, N45) into it. The mirror is scotch-taped onto that frame and lets the magnets be invisible after install.

yawns · Jan 8, 2018, 9:31 PM

Looks very interesting, nice alternative.
Would you mind making a short video demonstrating its functions?

tomster · Jan 8, 2018, 11:30 PM

I’ll have to ask my son on how to (properly do) do my first youtube video. But I will try to fly-wire my setup and show you how it works. Just give me a couple of days until I am back home mid-Jan.

tomster · Jan 10, 2018, 4:18 PM

I guess I’ll have to postpone the video. I wanted to get everything assembled and was rushing a bit too hard. Now the display is broken. Bummer.

yawns · Jan 10, 2018, 4:41 PM

@tomster
Oh my gosh. Now I feel guilty for having asked you :(
I’m very sorry

tomster · Jan 11, 2018, 3:34 PM

No need to have hard feelings. All I can blame is my-damn-self.
But there’s a German saying: There’s no bad thing that doesn’t also have something good to it.

At least I can now upgrade my display to a WQHD 2560 x 1440 one. I didn’t like the glitchy Full HD font rendering of the old display anyway ;-)
Downside is that the display I chose is yet not available.
But I’ll keep you posted!