Sunday, August 18, 2013

Arduino Trivia Buzzer System Update

So a quick update on my Arduino Trivia Buzzer System.  Last time, I gave you a basic schematic for the handheld buzzers.  Since then, I've completed 8 more handheld buzzers that are ready to be painted.

I needed a break from the handheld buzzers, so I thought I'd work on the control box.  One of the issues I'm having is that I don't really have the space/tools available to make the finished, shoe-box sized control box in my apartment.  Unless I can con my brother into making one for me, I'll have to find the room sooner or later, but in the meantime, I wanted to get some other work done for it.

Wednesday, July 17, 2013

Basic Arduino Triva Buzzer System Schematic

So it had been a while since I'd checked the comments to see if there were any non-spam comments.  Turns out at least two people wanted a schematic for the circuit I was using for my trivia buzzer system.  I whipped this together using gEDA on Ubuntu.



To find the value of the resistor needed, use an LED resistor calculator.  The pins used with the Player Buzzers would include any of the pins listed in the "user" array in my sketch, and the LED pins are in the "led" array.

If you're looking for some cheap circuit components, I'd suggest Thai Shine.  If I recall correctly, I ordered these LEDs and these pushbutton switches.  Unfortunately, Thai Shine doesn't list the forward voltage and current for the LEDs, and I don't remember them offhand.  When I can con my girlfriend into helping me make the rest of the handheld buzzers, I'll put up a new post with the schematic for that and provide additional details for the LEDs and resistors.  This should be enough to get you started.

Tuesday, February 26, 2013

Shapeways (Not a Women's Gym)

As you may have read about, I've been on something of an Arduino kick lately.  I've slowed down a lot on my trivia system, partially because for a while I considered a change to how I make each of the handheld buzzers.  I've been using PVC pipe and having to file out a rectangular hole in the endcap for the network keystone jack, but that leads to kind of an ugly, irregular cut out that doesn't perfectly fit the keystone jack.

This led me to Shapeways, which as the title of this post suggests, is indeed NOT a women's gym.  Instead it's a 3D printing service that will let you print your designs using a HUGE variety of materials for relatively cheap (they charge by the volume of your printed object).  I've been experimenting using Blender on Ubuntu to try to make my own endcap that will act like a wallplate and allow the keystone jack to simply snap in.  I haven't done any 3D modeling in over a decade, and I've never tried to do something that had to be a precise size for a real-world application.  Still, it's been fun.  My current prototype, which I haven't printed yet, is shown below:

My first attempt at an endcap.  It's shorter and has thinner walls than the ones I've bought from Home Depot, but it would still cost $3.21 +shipping to print at Shapeways.  This one just has a more precise cutout.  It doesn't have the full geometry to act like a wallplate for the keystone jack to simply snap into place.
Unfortunately, even with some of the changes I've made it would still cost $3.21 per part to print at Shapeways, which isn't quite worth it considering the ones at Home Depot cost less than $0.50 each.  Still, it was a worthwhile experiment and I've learned a lot about how to use Blender in the process.  I'm far from being an expert, but I'm definitely going to be on the lookout for cool ways to use Shapeways in the future.  I purchased the material samples kit from their website for $30 so I could see what the different materials looked and felt like before blowing a bunch of money on some actual prints.  It came with a $25 credit for 3D printing though, so now I have that credit on my account just waiting for me!

Seeing as I have all the materials for the trivia system already, I'll probably stick to filing and drilling the endcaps rather than printing them.  The cost just isn't worth it for the larger parts when I need so many of them -- at least not until I get my Replicator 2.  Please feel free to donate to the cause!  ;-)

Tuesday, January 15, 2013

Arduino: One Trivia Handheld Buzzer Complete

I've completed the first of my 25 planned handheld buzzers for my trivia buzzer system.  I've embedded a short video showing that it actually works below:



Tuesday, January 01, 2013

Thievery Caught by Geekery

So I live in a less-than-stellar part of town.  When me and my roommates talked to people about the area, they said they felt relatively safe, but if you have an aftermarket stereo, don't park on the street because someone will definitely smash in your window to get it.  I have a factory stereo and never leave anything in my car, so I wasn't too worried (my apartment back in undergrad wasn't much better).

Things were fine for the first year we lived here, no incidents at all.  But several months ago, at the end of July, something was stolen from our front porch.  My roommate ordered a used iPhone online, and it arrived in a plain cardboard box, nothing on the box or label to hint that it was anything valuable.  His wife came home to see that the box was not on our porch, but instead was sitting by the sidewalk, EMPTY!  It appeared that someone had walked right up to our porch, ninja'd said package, stolen the iPhone, and tossed the empty box on the ground.  The craziest part is that this happened in the middle of the day!

But unbeknownst to this thief is that they messed with what is arguably the most wired house in the neighborhood.  For shits and giggles, I set up a $60 wireless IP camera to watch our porch when we first moved in. It's mounted on the inside of the house, looking at the front porch through the small window above the front door.  I set up my media server to perform motion capture using Zoneminder, which would save a picture whenever it detected movement in the image.  My friends gave me crap every time they would come visit, asking "why the hell do you have a camera sitting above your door?"    Well, it turns out that being a nerd comes in very handy in situations like this.

The camera caught our thief: a young girl probably no more than 8 years old.  As the timestamp shows, this happened on July 31st, 2012 at 4:36 PM -- right in the middle of broad daylight!

Arduino: Trivia/Game Show Buzzer System

So I have a new addiction: Arduino.

The Arduino is a programmable microcontroller. It's a way to create your own electronics projects at home.  Ever wish you could have you garage door automatically close if you leave it open?  With the Arduino, you can (and I did).  I set up a small sensor that will relay to the Arduino when the garage door is opened. If it is left open for more than 5 minutes, it will close the garage door via a relay switch connected to the garage door opener.  Others have done similar projects in which they even hooked theirs up to their web server so they could close the door via their smartphone.  I didn't have much use for that feature, so I'm perfectly satisfied with my setup.  I've also read about other people making Pumpkin Tetris, security systems, windows that close themselves when a train is coming, and all kinds of cool stuff.  It's for the hobbyist nerd, definitely, but that doesn't make it any less cool.

For my current project, I'm making a trivia buzzer system, like in Jeopardy.  My girlfriend's family plays a few games of trivia like this every Christmas.  It's a lot of fun (I'll admit, I was very skeptical at first), but it's very low-tech in that everyone just raises their hand and her uncle is the judge of who raised their hand first.  It's all for fun, and [usually] no one gets too upset if they think their hand was actually up first.  But because I'm a nerd, I thought about how much cooler it would be if I could set up a system with handheld buzzers that would take some of the heat off her uncle.  At this point, I'm not planning on including scorekeeping, so he won't be entirely without a job.

Here's a short video of the prototype I built:



Wednesday, August 24, 2011

Oh, Hi There

As you've probably noticed, I've been neglecting Verbatio for quite some time now.  After finishing boards, I had barely a week before starting up with my clinical rotations.  My time is more limited now than it ever was during 1st and 2nd year, so my posts will likely be shorter and few and far between.

Rather than get into a long EBM post right now, I thought I'd say a little something about the HP TouchPad and how HP abandoned all WebOS hardware (though they say they haven't given up on supporting WebOS... we'll see about that).  As you might have read, HP has stopped production of all WebOS hardware (as in the Palm Pre line and the HP TouchPad).  Because of this, there was a firesale of HP TouchPads going for $99 over the weekend.  I was lucky enough to snag 2 of the 32GB versions at $149 a piece, as I'm hopeful Android will be ported over to the device soon to make it more useful.  At least I think I was able to snag them.  HP says they have my order and that they're slowly working their way through them, but I won't be entirely convinced until it shows up at my door!

It's been my opinion for a while that Palm's WebOS had the strongest UI of any mobile OS out there -- it's just a shame that their hardware sucked and there was so little developer support behind it.  WebOS just never got enough users to get people interested in developing apps for it, which is really too bad.  I preferred WebOS over Android (even CM7, though I do love the widgets and customization options), but WebOS just didn't have the apps I needed for school (Epocrates stopped supporting it shortly after I switched to Android).  I could talk at length about all the mistakes HP made when they purchased Palm, and how I wish Google had purchased Palm so as to integrate some of WebOS's features into Android, but Ars Technica had a pretty good article last week about what HP should have done with WebOS that is probably more worth your time.

I'll try to post more often, though for better or for worse, I wouldn't expect any really long posts any time soon.  So far I'm enjoying 3rd year, but I'm a little busier most days than I expected.  I'm almost 3 months into it, and I'm still not used to waking up early and working a normal/long work week!