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I am Iron Man

June 28th, 2008

When I saw the new Iron Man movie, I instantly knew I had to build some part of the suit (I like to wear gadgets). Luckily for me, I found an old hard drive that had just the pieces I needed for building a repulsor-like LED flashlight.

(This picture comes from IDontLikeYouInThatWay.com)

Objective

To build a very powerful LED flashlight mounted on my hand palm that would turn on and produce brighter light as I move my hand back (and the angle between my hand and my arm decreases and gets roughly to 90°). Also, the flashlight should be comfortable, allow my hand to move freely, be very sturdy, and of course look as much as possible like the repulsor Tony Starks wears on the picture above.

For those who have not guessed yet, this is what I was building.


Materials

  • An old (aluminum) heat sink (from a broken computer monitor I believe)
  • A long and thin aluminum piece from a copy machine
  • A street cleaner brush bristle (like the one used to build a Bogota Rake)
  • An aluminum disk and a thick aluminum ring (they were the holder and separator for the plates on a very old hard drive)
  • 6 5 mm and one 10 mm ultra bright LEDs
  • A linear potentiometer (from an old sound system equalizer)
  • A switch
  • An old laptop battery
  • Some cable, some female and male headers, heat shrink tubbing, a paperclip, a plastic cable tie, and lots of love.

How to do it

Since my materials are pretty specific and it is quite unlikely that some reader may get the exact same set of materials, I won’t give a detailed description of how it is built, but rather how I did some of the key parts of this contraption.

Shaping and shining the metal:
Since the heat sinks and the other peace of metal I found were not flat (they had many 90° bends) I hammered them on a piece of thick steel until they became perfectly flat. Then, they were sanded with a fine sand paper and polisher until they where nice and shiny with some tell wool (the kind used for cleaning). I always sand and rub the metal along the same direction so it gets a consistent brushed look .

I bent the metal with my hand and worked the bends with a heavy steel rod so they are round and smooth instead of straight edges.

Linking the hand and wrist pieces:
The wrist and hand pieces are linked together bu a street cleaner brush bristle. The bristle is bent in a “Z” shape and goes into a hole at center top of the hand piece. The other end of the bristle is slightly bent upwards (so it doesn’t go into my arm when I move my hand) and goes trough a wire tie loop on the top of the wrist. A paper clip is soldered into this end and is connected to the linear potentiometer. The I heated and Inserted the clip into the plastic potentiometer tab, this creates a nice and strong link. The paperclip provides flexibility and allows the and to move beyond the range of motion of the potentiometer.

I’m very proud of this link since it is flexible, robust, and is rather easy to build.

Light:

I used seven LEDs connected in parallel (since they have roughly the same voltage and current needs). They fit nicely into the seven holes in my metal disk. In order to avoid the LED leads to short when in contact with the metal, I applied a thick layer of transparent nail polish to the metal plate previous to inserting the LEDs. The nail polish works very well as an insulator and is, for all practical purposes, invisible.

The LEDs are connected in series to the potentiometer which in turn is connected to a regular resistor. The regular resistor is used to limit the current and set the appropriate voltage for the LEDs and the potentiometer determines the light intensity. You can determine the appropriate value for the resistor by using this LED calculator.

I hope you enjoyed the information and you like the end result.

Below is a video of the repulsor beam. I know it lacks the repulsive action but still, I think it looks nice. Enjoy.

Project

Inverted Pendulum

June 20th, 2008


My friend David and I implemented an inverted pendulum controller for the Quanser cart in th Control and Robotics Lab. The controller was implemented using Simulink and Matlab, which makes the tasks much simpler than dealing with microcontrollers and C.

We implemented many kinds of controllers, but the best turned out to be the full state feedback controller where we get to control the position and velocity of both the cart and the rod. The controller block diagram is shown below.


Below you can find the slides for a presentation giving a quick overview of this subject and a video demonstration featuring David as the presenter.

Project

Floppy Note Pad

May 28th, 2008

Inspired by this commercial product, my girlfriend and I did a small craft with her elementary school class (she is a teacher).

The main goal of this activity was to have the children make something useful by themselves by using everyday household materials and (what normally would be considered as) garbage.

Materials (per child)

Instructions

  1. Print the note pad paper model that is available in PDF or SVG. Make sure this is printed at the original scale. You may need to modify it to fit the margins of your printer.
  2. Take all the paper sheets and stack them while making sure they are well aligned together. Put the printed model on top of the stack and fasten everything with paper clips.
  3. Cut along the model lines. This should result in 48 small paper squares.
  4. Pierce the holes as shown in the model on every sheet.
  5. Bind the two floppy disks and the paper by using one (or more) pipe cleaner(s).
  6. Admire your creation!

Note: It turns out that the children are quite happy with their note pad and they even use it for taking notes (even if nobody prescribed them to do so).

Project

What am I building?

May 20th, 2008

I started building a contraption but I had to stop since I accidentally burned seven LEDs at once. Now, I have to wait until I get the new LEDs I ordered before I can finish. Meanwhile, you can try to guess what it is that I’m building.

My brother was kind enough to be the cameraman for this video.

Project, Work in progress

Home Automation

May 6th, 2008

Here is some information about a home automation system my team and I did some time ago. This was done for the Embedded Systems class and require two Altera UP1 FPGA boards, two computers and two USB-to-TTL wires.

- The nice picture above was done by Frank (see below) -

Although at the beginning of the project we were really motivated to do a robust and optimal design that could set an example on how to do home automation and that could be shared with everybody, the project quickly degenerated and the general design approach became: “We don’t care of how inelegant, inefficient or completely surrealist the system is as long as it works”. The main reason for this radical change was the implacable deadline that got closer and closer, and the usual lack of time Electrical Engineering students suffer from.

The system consists of a PC that takes high level decisions for the control of lighting, heating and power consumption in general for a house. This decisions are serially sent to an FPGA board that take some lower level decisions (such as debouncing switches, counting time, etc) and controls trough a very large number of IO pins (~90) the actual house hardware.

Since this is a small project, we do not have the actual house or its hardware, so we resorted to simulate it using a second FPGA board and another computer. The second computer controls the house status (temperature in each room, level of room light, motion in the rooms, status of the TV, etc) and offers an inteface so the user can turn on lights, move in a room, set the desired room temperature, turn on the microwave oven, etc. All this information is serially sent to the second FPGA board which then adjusts its pins status to mimic the house hardware.

- The GUI and the Java program was done by Yev and Ritvik -

All the coding was done in Java and VHDL and since it is not very well organized or useful to anybody else, I won’t be posting it. Nevertheless, the documents describing this project are very nicely done (all modesty aside) and give a clear description of what we did. Here you have: the SRS, the SDD, and the STC (not the final version). Please keep in mind that this documents are not published under the CC license, they have full copyright.Above you can see my friend Frank, he’s the leader of the group (transformed from the norm by the nuclear goop).

Just so you know, the project went well and allowed us to learn a lot. We even ended up having a very good mark, so everybody should be (and is) happy.

If you are wondering what did I do in the project (I’m sure you are): I did the serial communication protocol in Java.

Project