We needed to create a standalone kiosk-type terminal that we could have workers use to track their work, efficiency, etc. for billing purposes. Something that should/could have been done years ago, but it didn’t. Well, now I’m here, so weird projects like that can finally take shape.
The First Iteration:
When we first decided to go forward with this concept, we decided to use a Dell Latitude 10-ST2e on a clamping arm-mount, mounted to an electric/CAT5 conduit. Finding an appropriate mount was a little bit of a challenge. Finding a compatible cable lock was more difficult. Then the worst part was locking it down into a kiosk mode so that the users couldn’t get on youtube/facebook, etc. Their limited permission in GPO/AD would have prevented that anyway, but we figured that removing the navigation bar would remove any temptation. In its first form, it was inside a wooden box and looked like a Commodore 64. That got vetoed by the CEO, so we went with the arm-mount.
Well, for whatever reason, it never really worked. Part of the problem was the wireless connection. It’s something that needs work, but that part of the factory does not get good wireless at all. Despite our/their best efforts, that department can’t get on Pandora on their phones. So we bought an ethernet-to-USB converter. That worked. Not sure what happened at that point, but I guess they just didn’t want to use it. So it sat there, battery dead, for a few weeks.
The Better Iteration:
My boss had the idea to get a Raspberry Pi and strap it to a touchscreen monitor, and use that instead. So we did just that.
Took a while to get the correct storage medium, but eventually we had the Pi, a case, a microSD card, an Asus touchscreen monitor, and all the cables and adapters needed. Not the most exciting thing in the world.
I tried using Porteus Kiosk for this. It worked well running from a USB stick, but it isn’t ready for ARM processors, so it wouldn’t boot on the pi. Disappointing, but it’s alright. I decided to go with Raspbian instead. It has the advantage of remote administration that Porteus Kiosk doesn’t allow. There’s some kind of remote admin feature built-in to Porteus, but it didn’t look promising. And you have the issue of not being able to change things like the landing screen once it’s deployed. Using Raspbian instead, we can manage the thing via VNC, SSH, and make changes on the fly. It’s less purpose-built, but it works well on the pi.
I used Dan Purdy’s excellent blog post about this very subject. It really explains the whole process down to a T. After that, I used the instructions from eLinux.org to set up VNC server on the pi for remote administration. The one thing I had to do differently was set up VNC on :1 instead of :0. I guess :0 is taken by default on Raspbian.
Then yesterday, I finally deployed it. It wasn’t the prettiest thing in the world. Part of the problem was the curved back to the pi case. It left only 2 vertical strips about 0.5cm thick for double-sided tape to adhere to.
Part of the problem was supplying power to the pi. For this whole thing, I had to make do with what we had, for the most part. We had to buy the pi, the monitor, and the microSD card, but everything else was laying around collecting dust until this project began. As you can see above, it’s more than just the pi and a monitor. I ended up using a POE injector at the switch (TrendNet 5-port desktop switch), running a CAT5 cable to the mounting location, connecting it to a POE splitter, setting it to 5V, converting the DC out to USB, then running both network and power from the splitter. It’s a really roundabout way of doing what your run-of-the-mill $2 cellphone charger does, but it’s what we had on hand. Waste not, want not. Then we noticed the monitor only supports DVI and VGA input, so we needed a DVI-HDMI adapter for the pi. Since this screen is considerably larger than the Dell tablet, we bought an articulated VESA mount from some no-name dropship site.
Finally, I had everything put together. It wasn’t pretty, but it worked.
I came in this morning, went out to have a look, make sure everything was going smoothly, standard stuff. Nothing on the screen. I walked over and realized that the pi had fallen off the monitor (not surprised, really). But the cable zip ties had kept it off the ground. Someone had managed to pull the HDMI cable so hard that the connector ripped off inside the DVI adapter. Well that blows.
Cable Management Matters
I’ve been a subscriber of /r/cableporn for years. I don’t claim to be OCD, but there’s something really calming about what those folks do. What I made yesterday was nowhere near worthy. What I made today was also unworthy. But it’s a little closer.
My boss had the idea to zip-tie everything to the mounting hardware instead of relying on double-sided tape.
Okay, on the surface, it sure isn’t anything worthy of a centerfold. But I managed to sneak about 40ft. of assorted cable into 2ft. space, with slack to move the arm, but tight enough that it doesn’t hang down (so it won’t ‘accidentally’ get yanked again). All said and done, this probably took me two or three months to complete. However, all but two or three days of that was waiting on parts. Here it is, installed, on the factory floor, in operation: