“35 Hz” at W.A.V.E.S. 2016

Last month I was asked if I had any ideas for an illuminated art piece to temporarily install in the sculpture garden. I had no ideas, so I declined. A week later I submitted an idea and with the help of Sarah from Windsor’s HackForge, I was able to get some grant money to make it.

Lots of Bike Lights!

The design required 100 rear flashing bicycle lights. They were supplied ‘at cost’ by local bike shop City Cyclery and it took almost 3 hours to open each package and install the batteries. My idea was to attach the lights onto the riverfront fence in a sine wave pattern that accurately represented the wave length of a 35 Hz sound. The frequency was chosen because it was the same as the “Mysterious hum that is supposedly originating from Detroit’s Zug Island” (More Info).

Lots of rain!

I installed the sculpture during record rainfall that flooded the city. Unfortunately I didn’t have time to prepare a spreadsheet that would outline each light’s location on the fence, so I had to use a tape measure and calculator. I got pretty fast at using the SIN() button, but the installation did take over 3 hours.

Less Dead Cyclists!

Now that the sculpture has been taken down and an art grant paid for 100 bicycle lights, we will be donating all of the lights to places that can properly distribute these lights to cyclists who need them. I’m sure it’s not just a Windsor problem, but there are a lot of folks on bicycles at night that have no lights. Having recently started driving, I found it very startling the first time I came across a bicyclist on the road at night without lights. Hopefully these lights find their way onto the seatposts of some of these bicycles.

DIY Bedroom Workbench and Shelves

Over the last few months I’ve been working on a small electronics workbench and shelving system that can fit into my bedroom. I started out with a floor plan in inkscape until I rearranged all of the furniture to maximize space and then designed everything in CAD. Everything is made out of plywood and assembled with a brad nailer and glue, the supports for the shelves are made from 1.5″ aluminum angle stock with holes drilled every 3″.

The desk height adjustable and appropriate for standing and has a self-closing drawer for hand tool storage. There is an integrated shelf for test equipment and this also holds a rackmount power bar that powers everything on the bench. The surface of the desk is covered with an ESD mat with attachments for grounding straps.

Underneath the desk fits a storage cart that holds 6 divider bins and also has a drawer for more hand tools. The cart is on industrial locking casters to be pulled out as a second work surface. After my first late-night stubbed toe I added glow-in-the-dark markers to the corners as well. The shelves are 1/2″ plywood and held together with t-nuts and bolts. I also used 1/16″ stainless steel aircraft cable and turnbuckles for stability and casters for easy moving.

So far I’ve been very happy with the setup and so has nin and bubs.

Stuffomatic – manual “pick and place”

I finally got a chance to test out this little invention I call the “Stuffomatic”. It is used for stuffing circuit boards with components by lighting up the correct part bin. It is activated by a footswich, and uses a Teensy 2.0, buzzer, OLED 2×16 character display and a MAX7219.

While manually stuffing and hand-soldering Therevox circuit boards, I wanted something that would speed up the process and cut down on errors. On first test, the stuffomatic seems to speed up the “stuffing” process by close to 30%. Grabbing a component directly out of the lit bin is also a lot less prone to errors, compared to the normal way (reading the reference off the board, cross referencing it with the Bill of Materials to get the part value, find the right value part bin, grab the part).

The stuffomatic advances to the next part when a footswitch is pressed. I used a buzzer to make a small “click” noise when the footswitch is pressed for some audio feedback. There is also an “up” and “down” switch on the stuffomatic to quickly go through the list of parts.

The only problem with this project was that the Teensy couldn’t store the entire BOM (bill of materials) in memory. Instead, larger amounts of data need to be stored in PROGMEM which requires very messy code to declare the variables. To get around this, I wrote a PHP script that reads a CSV file and outputs the PROGMEM variable declarations as a 2 dimensional array. This also makes it easier to recompile the stuffomatic code for different projects.

On the front of the stuffomatic is a “note” LED to draw attention to the display if there is a special note or instruction being displayed. The stuffomatic can show messages like “flip board over” or “solder”, or a specific component might have a note with it.

So far I’m happy with the stuffomatic, it did take a lot longer to finish than I expected, but building it was more fun than stuffing circuit boards.

Garage sale speakers, counter top and dust

Nice luck = finding a pair of studio monitors for $10 across the street at a garage sale several days before starting to mix an album!

This is a counter top I made out of some maple. It is finished naturally, but I probably should have stained it a bit “colder” to remove the pink-ishness that maple seems to have under cfl.

From the winter, very dusty! I gotta say that a full face mask for wood working is pretty awesome. It makes you feel like an astronaut and you can never forget your safety glasses – Norm would be proud.

Super Fan prototype #1

Some pictures of my first prototype window fan. Trying to not use the AC again this summer, but my crappy garage sale window fan ain’t cutting it. I’m using a 12″ diameter 12V 80W automotive radiator fan and a high efficiency 100W switch-mode power supply. The fan is rated to be 1600 CFM, I can’t measure to verify but it definitely moves a lot of air.

I was hoping to make something that moved a lot of air but didn’t use a lot of electricity. These radiator fans were the most efficient I could find, and the total draw is 88W which is less than my off-the-shelf fan and a lot windier (breezier?).

One toggle switch for power, another for fan direction. The off-the-shelf fan I was using previously had to be removed from the window and put in backwards to change direction, so this is a very satisfying $3 direction switch.

I also added a metal frame to hold a 2″ air filter and foam pre-filter. The hope was to filter the air before it gets sucked into the room through a MERV 13 filter since we live on a very busy street. The metal frame was laser cut and bent on a small brake.

Unfortunately the filters really affect how much air the fan moves, almost stopping it entirely. That’s prototyping though, otherwise the fan is working great. The air isn’t being filtered before it comes in though, but I scored a second-hand austin air healthmate for cheaper than I could build something similar.

The fan motor surface temperature got up to 60C after being on for about 30 minutes, not sure if that’s a problem yet though. Woo, prototyping!