Simharry3's Ramblings

Sound Reactive LED Schematic

Simharry3 — Fri, 20 Apr 2012 16:13:26 +0000

Lots of people have been asking me for a schematic for my sound reactive circuit shown here:

So without further delay, here’s the schematic:

Note: You’ll have to add resistors based on your supply voltages and your LED voltages. The two LEDs I used ended up not needing a resistor, but if you use a higher input voltage, or have less-powerful LEDs you’ll need to add a resistor between the + voltage and the LEDs.

Woodward Internship

Simharry3 — Wed, 15 Feb 2012 04:58:01 +0000

Recently I did an internship with Woodward, INC. I learned a lot from the experience, especially about how to work with integrating machinery with people, and how to make devices that are user-friendly(ish). During my internship, I developed an Arduino-based torque recording device to take input from a torque driver (a machine that screws bolts in with very precise tightness), count the number of torques, and then export it to another employee’s project, which was a database to store all of the torque values. The prototype was named (creatively) the Arduino Torque Recorder, and there is currently a prototype machine out on the assembly line. Surprisingly, the hardest part of this project was developing a way to make the ATR able to communicate with the humans running the machine, and it took me the longest amount of time to develop the GUI that allowed the user some flexibility. The project was very frustrating at times, but I am glad I persevered, because I think it was a valuable learning experience, not only about how to work through difficult problems, and being able to learn new things to get a project to work, but also how the work environment is, and how to deal with deadlines effectively. I’ve attached my formal presentation, product proposal, and bill of materials if anybody is interested in looking.

Product Proposal

Product Presentation

Bill of Materials

Pulsejets and more!

Simharry3 — Wed, 15 Feb 2012 04:47:37 +0000

Here’s some video of the latest project a friend and I are working on: Pulsejets, and other forms of producing thrust! While the project started out as trying to make a pulsejet, since the final product can’t sustain itself without compressed air to feed it, I’m not sure it can really be called that.

In the first video, the engine failed because the epoxy we used to join the pipes together (JB Weld) failed at such a high temperature:

In the second video, we made some changes. First, we sanded off as much of the JB Weld as we could, then crimped the pipes together. The smoke coming off of the engine about halfway through is the rest of the JB Weld burning off. Second, we coiled the propane intake tube around the combustion chamber in an effort to A) cool down the combustion chamber with the liquid propane, and B) heat and pressurize the propane as it entered the chamber. This design worked much better, and was able to sustain itself without melting:

We are currently working on a third design, which totally abandons the pulsejet design in favor of a much simpler system.

Arduino Powered Mini-Bot: A 24 Hour Robotics Project

Simharry3 — Mon, 06 Feb 2012 17:12:02 +0000

We had a lot of snow this Friday. This meant that I was snowed in, and since the snow meant I couldn’t work on my Sparkfun AVC (Autonomous Vehicle Challenge) Vehicle (even frozen water is not kind to electronics), I decided to busy myself with a new project. It started out as just some experimenting, but then I decided to turn it into a full robot, and here’s the result. Enjoy:

3D Printed Rocket Part 4: The Launch

Simharry3 — Mon, 06 Feb 2012 17:06:53 +0000

Well, the moment you’ve all been waiting for is here. Unfortunately there may have been some slight instability issues, so the launch didn’t go exactly as planned. However, this means you can look forward to parts 5 and 6 where I fix the rocket and relaunch it! In the meantime here’s the video:

3D Printed Rocket Part 3: Fins

Simharry3 — Mon, 06 Feb 2012 17:02:55 +0000

In this video, I design and print the fins for the rocket. Unfortunately my camera ran out of battery about 1/3 of the way through the print process, so the whole thing wasn’t captured, but you get the idea:

Sound Reactive LEDs with TIP31 Transistor

Simharry3 — Sun, 06 Nov 2011 17:21:34 +0000

Recently I built some sound reactive LEDs to put into my gaming computer:

They are on a custom etched circuit board, and it is the first circuit board I’ve successfully etched. I think it came out pretty well:

It was a simple circuit, and I used a really thick sharpie to act as the resist. The transistor is actually already attached, it’s just on the back, since I didn’t want it on the same side as the LEDs:

Here’s a picture of it on it’s 3d printed bracket:

And finally, here it is mounted in my computer:

3D Printed Toilet Paper Tube Rocket Part 2: Nosecone

Simharry3 — Fri, 07 Oct 2011 17:43:52 +0000

Here’s part two of my latest project:

In this video, I design and print the nosecone for the Toilet Paper Rocket. The print took 1 hour and 5 minutes total.

Printable Toilet Paper Tube Rocket Part 1: Engine Mount

Simharry3 — Mon, 03 Oct 2011 00:57:01 +0000

Time for a new project!

I will be designing and building a rocket that uses only 3d printed parts, a parachute, some string and a toilet paper tube. Here’s the first video in this 4 part series:

The engine mount was designed in Autodesk Inventor, and then printed on a modified Cupcake CNC 3d printer. The print took 57 minutes in total.

Canon T1i Remote

Simharry3 — Sun, 21 Aug 2011 16:27:37 +0000

I like to take pictures of lightning and stars, but the only problem is that these require relatively long exposure times (15 sec – 2 min) so holding down the shutter button for that long causes some camera shake from my hand. Therefore, I decided to build a remote to control my camera so that I don’t have to actually touch the camera itself. Here’s what the remote looks like:

The bottom button auto-focuses the camera (although, since lightning and astrophotos are in the dark, manual focus is normally used). The middle red button takes a picture for whatever length is set on the camera. It’s just like pressing the shutter button. The toggle switch on the top acts like holding down the shutter button. If a shutter time is set on the camera, then it will continuously take pictures for the set time. Otherwise, if the camera is set to “bulb” mode, it will lock the shutter open for as long as the switch is toggled. Here’s a picture I took using the remote:

To see the full-sized picture, please visit: simharry3.wordpress.com