…what do you want to make today?
Project 2

What’s better than the click-click-click of a typewriter? It’s so much more physical than a computer keyboard – you have to press with more force, your hands have to move up and down more, and then you’ve got the carriage return and paper rollers – it gets you much more involved with whatever text you’re producing. I’ve got nothing against keyboards – they’re incredibly efficient little things, and there’s a lot that gets accomplished from them being around. The keyboard and mouse are the two instruments we use to create this binary symphony of information we have within computers(a little too far? maybe). But what if we were able to make a keyboard as physical as a typewriter? Yep, you wouldn’t be able to type as fast, yep, you’d have to interact with it in a much more conscious manner, but (I should make this my motto) Wouldn’t it just be so cool???!

So that’s what I’m doing. In fact, this was my first electronics project ever. I found this guy’s attempt at it, and I’ve already created two prototypes that have kind of worked. We’ll say that at least 50% of those keys worked, but my latest attempt is probably my best (and most presentable). The first one was grossly messy and took at least 80 hours of work to make (I was out of a job at the time, so it was a good way to pass the time). The second one was part of a school project, and I made my own circuit board for it, but it still wasn’t fully functional. So the latest one was great (in my mind) until I found this: USB Typewriter. NOOOO!!! Someone stole my idea! Well, someone stole an idea from me, that I also kind of borrowed from someone else…

After finding that, I put the project on hold because I lost my motivation. So fast forward a year or two, and here we are, ready to finish it. I’ll get some pictures or video up once we hit that point, and for those geeks out there, I’ll now talk about how it works.

How It Works:

The basic concept is that when you strike a key, I want it to complete a circuit, much like pressing a switch. Now, this is simple in theory, but when you’ve got over 40 “switches,” you have to find a way to make everything work. Rather than connect this to a circuit board taken out of an existing keyboard, I plan to use my Arduino (it’s so Ardreamy!) to emulate a keyboard, and it will use its inputs to figure out what switch was pressed. Now, to do this, there are a multitude of ways, but I’ve decided (or rather, I decided a couple years ago when I made the circuit board) to use the analog inputs and a voltage divider approach. I’ve created a circuit that uses four analog inputs and about 40 resistors to create four resistor networks that will output a unique voltage when a key a pressed. The circuit in its default state is all open, so once you press a key, the Arduino will see a voltage on input #4, and because that voltage is 3.7V, it must be the letter “E.” This is the easy part. The code will start up and prompt you to press each key so it has a reading to go off of, and then it will go into “keyboard mode.”

The hard part is getting the shift, space, and carriage return to work. These things don’t have a secure surface on which to mount any kind of sensor, so I’m still trying to figure out how to make this work. The USB Typewriter guy uses reed switches, but those things (to my knowledge) only close when in a magnetic field, so I don’t know how that would work unless you put a magnet in the surface that passes it. If anyone has any ideas, I’m open!