Thursday, April 30, 2015

Making a shape out of wood.

So, I regrettably don't have a lot of photos still of the first project we did this year, but I do have a couple of photos from the process of making my octagon, so I figured I would make a quick write up. 

The first step was cutting all the boards to the length of an outside edge! Then, beveled edges at 1/2 the angle of the shape you're making. I also cut this wedge of the bottom to make space for tuners. All of this is done on a table saw and is relatively straightforward if you go slow and have a miter gauge!

When working with plywood, you're usually good to glue with no fancy joinery up to a miter of 45 degrees. However, solid wood requires either a finger joint (easy for a square) or a tongue and groove joint in the case of the octagon. This is to keep our ratio of end grain to long grain in check. Long grain is good for glue joints and end grain is useless!

With all the sides cut, I put them end to end and used packing tape to go over every joint.

Which allows flipping the whole system over! Then it's time to apply the glue.

After glue is on every edge, the tape is used to tension the boards into shape, but "closing" the loop. Then tape goes across, around, back and forth and everywhere.

That's pretty much it!

Installation Project documentation!

Here is a blog post detailing the process of making this installation:

The original concept here was to build an environment for meditation, and I was enamored with the idea of a box for quite some time. I spent a lot of hours in my basement prototyping joints that I didn't end up using, but it was definitely a valuable experience in terms of refining a process! This is a glue up I did of the joinery that I will use eventually to make the box:

After some friendly prodding from Eric, Takumi, Kevin, co. I was convinced that a box is NOT an interactive art installation, and that I should build the interactive, functional part of it first. So, I worked with my test rig from last project (the old trusty guitar amp) and found a few sheets of metal that I really liked the sound of, and that I could glue a magnet to in a place of actuation. From there, building a reliable and simple mounting solution was the next step. I tried a few ideas, but the sturdiest and best sounding was simply a 2x4 with the end recessed for the magnet. Here's a prototype in action:

One of the stupid little bugs of this project was not having the right size of screws! But I fixed this with a whole saw. It also keeps the screw out of the way for when I finally but these in a larger structure.

The next (daunting) step was finally conquering the amplifier question. One of the problems I had with the last project was dealing with the complicated "mute" and "standby" pins on the LM1876. It also had a pretty fussy power supply window of operation. For this project, I opted for the simpler, one channel LM1875. I was able to assemble the circuit below, which is basically just running the signal through the amplifier with a few filters. I also have capacitors used to bias the power supply into true -12v, 0v, 12v submission. This is done with a large and small cap (1000uF and 0.1uF) in between -V/+V and GND,  respectively. 

Once this was done, I made nicer versions of the mounts and reduced the noise with some rubber stoppers. The final systems came out really nicely, with the perfect alignment between magnets and a good amount of structural integrity. Also, some sanding and nice stain. Polycrilic is to come!

Not pictured here is the journey of creation I took with the meditation object (aka pokey pyramid). This was a super important part of the interaction so I dedicated a lot of time and thought into how it should feel and look. I ended up cutting a design on the band saw out of sheet metal, bending it into shape, and texturing it with weld material. Then I sandblasted it, used gun blue to get a darker finish and waxed it to seal the metal from oxidization.

Tuesday, April 28, 2015

Wireless Arduino-To-Arduino Communication

For my project, one of the arduinos needed to freely rotate, so I couldn't just run a wire from one to the other. So, I started looking at different wireless modules and found this post on stackexchange really helpful in explaining the differences between all of them. In my case, I could have gone with the XBee, the Nordic nRF24L01, or a barebones radio transmitter and a receiver. The latter might have been too unreliable due to interference, and the XBee was a bit expensive (also I had heard they were hard to configure.) So, I ended up going with this nRF24L01 breakout from Sparkfun, and I'm really glad I did. (You can even get them way cheaper on amazon if you're fine with an on-chip antenna).

The first step is connecting to your arduino. To figure out which pins to use, read the Connections section here. I used the muli-purpose IO pins (11, 12, & 13) for one arduino and the ICSP pins for the other; either works fine. Also, the library I used defaults to pins 7 and 8 for CSN and CE, respectively, but you can change these to whatever you want. I used 8 and 9.

Speaking of libraries, here it is. I like this one better than some of the alternatives because it seems like the interface is as simple as possible, while still using the nordic's auto-retransmit and auto-acknowledge features to ensure your packet always gets where it needs to go. The first link in the github readme gives some example code, which is more or less exactly what I used. To see specifically what I did, check out my code on github here.

Monday, April 27, 2015

Hiding the Menu Bar

Here is a quick post about something I found very useful for this project.

Since I'm displaying video feeds on my laptop screen, I needed a way to hide the menu bar.

The way to do that is very simple...
Just create two message objects as shown in the photo.  Then click on them to hide/unhide the menu bar.

UPDATE:  You can do the same with mouse cursors!

Sunday, April 26, 2015

Jitter Journey - Detecting Movement

My project mainly consists of Jitter, so I'm going to make some blog posts about what I did with it.

For the interaction, I wanted Max to detect motion and use the motion data to manipulate sound and visual.  Luckily, somebody made a patcher that fulfilled my need.

Hold Still is a patcher that uses frame-differencing to detect movement.  This simple and straightforward patcher uses video sensing to control sound synthesis.  

Hold Still is #32 in the Jitter Recipes. Download the patch here
You can read more specific details about how it works on that link.

I mapped the movement values to groove~ object to manipulate a glitch audio file.  The amplitude of the outputted sound is then mapped to jit.sprinkle object to manipulate the video feed.  

I also used Hold Still patcher to sense if a person is looking into the peephole or not.  I set the threshold very low in order to detect slight eye movement.

It looks like Isaac is using Hold Still for his project as well!

Very useful.

Thursday, April 23, 2015

I apologize for the vertical camera footage, but progress has been made! Here I am having the program draw a red dot where I push-- calibration is still a little off, and I'm honestly not totally sure what I did to make this work (I had been trying so many things for the last 10 hours, and it just started working, with some combination of those things) woohoo!

Tuesday, April 21, 2015

This is more or less a proof of concept for the users' interface, as well as a demonstration of state change while users interact (or don't!) with her. Along with the two pushbuttons, the LCD object in Max will likely be the only interface that the users will have. I'm probably going to display LCD on a separate monitor next to the fish tank. This allows me to position my computer more conveniently to hook things up, and it frees up a lot of space for the buttons.

Monday, April 20, 2015


 Projection mapped in Processing and depth sensing, trying to combine the two now!

Rosella's Modern Life


These are some storyline sketches. This project will be story-based and "constructed." The things I will be lowering into Rosella's aquarium will be generic because I want the narrative to shape the interaction. The crux of the piece is that while all it really is is a fishtank with a snail inside, we're inclined to assign value and sentiment to Rosella and the things we drop into the tank.

Speaking of dropping things into a tank, I was able to use a continuous servo to drop an item in:

Since the screen will be the peoples' main interface, I want to do the project in Max. Maxuino fits my needs perfectly, since all the Arduino is doing in this project is lowering and raising objects. As shown in the video, all I need are some timed bangs on float boxes to get them spinning equivalent distances. That's also as fast as I could make the servos spin, but that's not a complaint. Don't want to crush Rosella.

Two buttons will be the primary mode of interaction, with each button deciding what Rosella "does" in her life. I want it to be similar to the King's Quest series, or maybe more true to the concept, Peasant's Quest by HomeStarRunner. The narrative will be completely ridiculous.
  • Rosella goes to the mall.
  • She (you) decides to fill out one of those "win a boat" sweepstakes forms you see all the time
  • She miraculously wins the sweepstakes two weeks later but the company fulfills the sweepstakes has since been foreclosed
  • As a "consolation prize," they give her the (now ex-) CEO's firstborn child, Frank
    • A generic snail toy model is lowered into the tank
  • Rosella goes about her business, encountering other events
  • 5 real minutes later, Frank runs away, leaving a note that says he left to "find his passion in above-water basket weaving"
    • The snail model is raised back up
Moving forward I would like to create a structure out of wood that holds servos securely and is able to securely sit on the top of the fishtank. I see laser cutting in my immediate future.

Sunday, April 19, 2015

This post is half project update, half rant about the Xbox Kinect/Windows Kinect, and the incredible struggle it has been to get the Kinect to "connect" buh dum chee!

It's now been about two weeks of wrestling with these products to talk to my computer. Basically, I tried EVERYTHING! I struggled to get them working on Mac, but had huge problems with out of date software and drivers. A basic summary: Two versions of Open NI: Simple Open NI and Open NI 2.0. After Open NI 2.0 was made the project was shut down, and this was several years ago. Since many new products have come out since, a lot of the tutorials have unanswered recent questions on how to get these new hardware devices to work with old software and old sample code. Also, almost everything you will find online about this is an unorganized mess!! It's scattered around by users instead of put out by the developers. Windows makes the Kinect and Windows or Mac do not really seem to want to make it work easily on a Mac. Fine, I get that. So I downloaded the Bootcamp Windows 8 Partition on my computer. That resulted in a whole slew of other problems, with drivers not working at first, internet not connecting as a result, blah blah blah, got that worked out eventually.

Got everything going and didn't have enough space to install the software. Moral of the story I learned- DO NOT give Bootcamp the minimum amount of space required for installation, cause then it's useless if you want to do anything on it. Reinstalled Bootcamp with more space. Okay! Should work now! NOPE.

I already hated Microsoft a bit, since memories of my insanely slow and old Dell computer at home are pretty much all I associate with the company. But the uninformative website, complete lack of helpful information in error messages, and totally incompetent help phone line has taken my burning hate for Microsoft to a whole new level. I digress, basically, if you have the newest version of the Kinect for Windows (2.0!! NOT IN THE TITLE! THEY DIDN'T NAME TWO VERSIONS DIFFERENTLY!) then, I would assume, if you download the software for the updated SDK 2.0 on the Kinect for Windows website, you will have it working perfect in no time. However, there is an older model of the Kinect for Windows, with a different model number, that is super easy to differentiate because it looks different, and yet there is no place to "click here if your Kinect for Windows looks like this and download the OLDER SDK drivers." Anyways, rant over, that was the solution. The older SDK drivers got the Kinect to connect! Still only running samples, have to figure out how to get the sample code into a compiler that I can pick up and run with for my project. Also still having issues getting Touch Designer working, I have the NIVIDIA graphics card you need, but it seems mine may be a different model. Overall, finally made some progress. Final thoughts: Mac needs to come out with an alternative to the Kinect or better integration! Windows is the worst, forever and always.

I hate Microsoft. Finally got the Kinect to be seen by the computer though.

Thursday, April 16, 2015

ESP Levitation (actually just a webcam and a fan)

For my project I decided to do an interactive alternative to Erwin Redl's "Ascension (thirty-one)"  using a pretty similar mechanism, a ball in a tube being levitated by a fan. The video above is me playing with the prototype, made with acrylic tubing, a squirrel cage fan (from sparkfun), plywood, a ping pong ball, a mosfet, an arduino and a webcam. Imagine its like the worlds fair or something, and stay tuned for the upscaled (not janky) version!