So, the STAR TREK DOOR has been a slow, “back-burner” project for a while. Recently, I got a little time, so I sat down and figured out how to hook up the air valves to a set of relays, and control those relays with an Arduino.

Here’s a video overview of the physical doors themselves and how we plan to open and close them with air valves.

This is a joint project, working on this with my brother-in-law, Fred. The doors are between his garage and workshop. Fred has been working on the doors themselves, the wall and framing, and mechanical connections. I’ve been working on figuring out the software, controls, and electronic magic that will drive everything.

IMG_6655IMG_6610The physical doors themselves are done, except for paint. Fred has also been making a pretty neat frame for the garage side. He cut alternating widths of wood and then glued them together for the nice light-colored wood on the inset of the planks that will frame out either side of the door. A similar piece will cross the top of the door.

I got all the main components – Arduino, breadboard, relay board, 12V power fuse panel, and air valves themselves all screwed to a piece of plywood. At this point, it’s not pretty, but it is functional.

IMG_6652We have a nice industrial door control with OPEN/CLOSE/STOP buttons on it. Those are momentary on buttons, but through the power of the Arduino, I can make them be whatever I want. I started with a Button Tutorial, and then modified it to suit my purposes, and added a Delay(1500) command after activating the air valve. That way, the valve will stay open long enough to fully open or close the door, even if the button is just pressed for a moment.

I programmed the pin for the STOP button to test out a sequence to open the door, pause (long enough for a person to walk though,) and then close the door. It seemed to work pretty well. If the timing is wrong for the real-world application, all I have to do is simply change the delay times. (It will also need a safety. We don’t want the door closing on a person!)

IMG_6520At this point, the basics of the control panel are working. The STOP button is just wired up as a “stand-in” for a single button we already have installed on the garage side of the door. It’s a capacitive touch button that lights up either blue or white with internal LEDs. It’s a neat looking button, but it’s only a SINGLE button. So, it needs to have functionality to both open AND close the door. I’d also like to explore using a variable in the Arduino that states whether or not the door is open, and then changes the functionality of that button based on whether the door is open or not. The air cylinders themselves also have built-in position sensors, which would be neat to use possibly as both a safety AND a “Is the door open or not?” sensor.

Here’s a video clip showing all the components actually working together. At this point, if the panel was simply mounted above the door, and air connected between the compressor and air cylinders, we would actually have functioning doors.

IMG_6653I don’t like the look of how the air valves and tees are held together right now. I was able to find some not-too-expensive push connectors (similar to PEX Sharkbite style) for air, which might make it a little easier to connect all the air components and look cleaner. Once I really have everything finalized on what’s going on at the breadboard, I also need to decide if I want to pull the breadboard out and replace it with a custom circuit  board. One thing I DO need is a simple way to connect the tiny pin connectors to the larger wires going to the buttons AND provide strain relief. For the moment, I just used staples to nail the 18 ga lamp cord wire to the plywood and then made the electric connection with alligator clips. What would be the BEST/CLEANEST way to do this? Some sort of small screw down terminals?

I also have a rather large fuse panel mounted on the plywood. It was free, and I already had it. It supports many separate circuits, but for this project, a single DC fuse would probably be fine. I’m also using a bit of an overkill 12V power supply. I’ll want to replace that with a simple wall-wart. Lastly, the Arduino is running from USB power. I’ll need to solder up a 12V DC barrel connector so that it can run off the same power as everything else. I think we will make a switched electric outlet, and plug the wall-wart in to that. If the system is ever not working right, just switch off the power and manually open and close the door as needed.

I’ll definitely want to hang out with the guys at the Makerspace sometime soon talking Arduino, specifically how to integrate some more sensors and get feedback used to activate the doors fully automatically.

-Ben Nelson

Let’s Detonate!

Dan Loves Fire!

Dan loves fire! It’s a fact! For Maker Faire Milwaukee we made a fire poofer which was triggered by pressing a button. Tons of kids (and adults) pressed that button over the course of the weekend.

While Dan the Blacksmith (and John McGeen from BBCM) were the primary builders of the fire poofer, I did the trigger electronics and enclosure.

The Detonator

I’ve written up a blog post with lots of images explaining the (somewhat rushed) build of the device. It’s Arduino powered, has some relays and a beeper, and looks semi-nefarious. Read more about The Detonator.

The Detonator Insides

The Turndrawble

The Turndrawble

The Turndrawble is a drawing machine I designed, based loosely on an old vinyl turntable, but instead of playing records, it creates drawings.

The construction was done using stacked layers of wood and acrylic. I wanted to avoid using the typical laser-cut “box” enclosure I usually use. I’m pretty happy with how it turned out.

The Turndrawble

The Turndrawble is meant to be used to create 12″ circular drawings. One of the knobs controls the platter speed, and the other sweeps the arm in and out. Since it’s a new drawing device, it hasn’t been mastered yet, but we’re working on it!

Here’s a short video showing the turndrawble being operated. I’ll probably have it at some future art events for people to try out and see what they can create with it.

There’s a bunch more info about this thing on the Turndrawble project page on my web site.

QWERTY (and nothing else)

QWERTY Keyboard

I built a QWERTY keyboard that types the letters Q, W, E, R, T and Y, and nothing else. No space, no return, no escape.

It’s a fully-functional USB device, you know, as long as you just want to type words that can be composed with Q, W, E, R, T and Y. (WET, WRY, YET, TRY, there’s a bunch of them!)

I wrote plenty more about this project on my blog, and if you want to read about the history of the QWERTY layout, and its connection to Milwaukee, and why the way we interact with technology is interesting and sometime ridiculous, well… I got that too.

The never-ending 3D printer project

MegaMax has been and continues to be my main project for the last 2+ years.  I am currently working on some upgrades that will make him more Mega and even more Max.  The Y axis is being converted from belt drive to screw drive and the round guide rails are being replaced with linear guides and bearing blocks.  The X-axis will also get converted to linear guide and bearing block and change from 5mm pitch belt to 2 mm pitch belt drive.  I feel confident saying that once these modifications are complete the flaws/errors in prints will be due primarily to the nature of liquid plastic squirting through a nozzle, not positioning system errors.

I recently updated my web site with a sort of historical look at the project, including all the mistakes I’ve made along the way and the often failed attempts at correcting them.  Here is the page that shows how it all started, how it has ended up, and where it is going.

Don’t ask me why I do this-  I have no choice.

MegaMax beginning

From this…






















MegaMax present state...

To this…