Monday, April 16, 2012

Lebanese OCTO Copter built by Mounir Zoorob

A few days ago, I bumped into Mounir Zoorob's OCTO copter project. It is a very impressive flying monster that Mounir designed entirely by himself. It is 1m in diameter and it has a 3 axis camera Gimbal, all designed from scratch. Apparently he has spent over 4 months very hard at work to finish it on time. I must say he did a pretty amazing job. So I invited Mounir on DepotBassam to write a small review of his OCTO copter flying machine, and here is his post:

Before starting, I would like to mention that the materials used are not the best choice. However, since there was nothing available in this part of the world and shipping carbon fiber parts was not possible I had to go with aluminum and Plexi glass instead. (on that subject, review DepotBassam's post on Lebanese electronics shops for more info)
I used 2cm * 2cm * 1 mm aluminum square tubes and the motors are from DIY drones with 35cm wires 2836/9. Each engine has a thrust of 1300g approximately.


I'm using Ardumega from DIY Drones as the main controller with magnetometer + sonar. So far it has proven to be the best thing I have ever bought for this hobby. i enjoyed it so much i bought it as a kit and soldered everything together


I designed and laser cut the case from a 3mm black plexiglass to hold both the Ardumega and the receiver.


As for the motor controllers, I bought 8 25AMP Turnigy ESC's from HobbyKing.
I am currently using 11*4.7 props but will go with the 12 later on down the road. All well balanced


Ardumega will be responsible for the compensation on the roll/pitch axis at the moment. Later on, I will upgrade it to control all three axis.

This is my camera gimbal. It currently has 2 active axis , but later on I will upgrade it to 3 axis. Currently I'm working on finalizing roll and pitch, but I am still waiting for the right parts to arrive.   
Wires were also taken into consideration during the design phase :) very neat :) 
Wires from the ESC's  to main power source are all well soldered and added heat shrink.
Here's the OCTO almost ready for a test flight :)

Here is the OCTO after couple of flights. I modified the design of the Gimbal and I integrated a new landing gear design on it
I promise the next design will be more elegant. With the cash at hand and the time this is the best I was able to come up with.

Here is a sample picture from the video I'm taking from the OCTO


Here is the first video from the OCTO, of course it looks better now but this is just a sample.



For those who love beer, here's one for you :) Note: I got rid of that beard
Feel free to ask me anything, your feedback is important to me. It better be a good one though!

Saturday, April 14, 2012

Wall Mounted Double Pendulum for Experimental Photography

(or how we went to outer space shot some galaxies and came back)
Through the lens of Abir Ghattas

My first interest in chaotic behavior can be traced back to this post. This time however, instead of simply developing a simulator I decided to build a real double pendulum. Watching a double pendulum dance erratically was worth a million simulation. If you are follower of this blog you will realize instantly that I could never let this opportunity pass without transforming it into some sort of a crazy experiment (-mostly photographic-).
 
The first step in the process was the design of the pendulum. The dimensions were chosen such as to maximize the chaotic behavior. Click here to download the AutoCAD .dwg file.

All dimensions are in cm
The material was chosen to be transparent 2mm thick plexiglass (4mm would have been ideal-but it was not available). The reason I chose to use a transparent material was so that the light can pass through in photography. I would definitely choose another material if I was using the pendulum for decorative purposes.

As for the components needed:
- 6mm ball bearings x4
- 6mm Hex Screw with nuts and washers  x2
- 3mm wall mounting screws and screw anchors x2

The following slideshow displays the assembly process


Here's a video of the double pendulum in action


After the assembly, Abir Ghattas and Patrick Abi Salloum came over for the photoshoot. We used LEDs of different colors connected to 3V coin batteries and we took long exposure pictures in the dark.
Left to Right: (1) Abir painting the pictures with LEDs (2)focusing (3) Patrick vs. Abu Ali
Courtesy of Patrick Abi Salloum

"Angel of Death" courtesy of Patrick Abi Salloum
For the result check Abir's website: http://abirghattas.com/double-pendulum-experimental-shoot/
and Patrick's flickr: http://www.flickr.com/photos/patrickas/7072749767/in/photostream