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Posted by RotoRex | Dec 04, 2016 @ 12:22 PM | 2,316 Views
I have set myself a goal to develop my YouTube channel some more. I want to commit to posting once every other week and producing higher quality and more engaging content. To kick things off I made a new trailer for the channel. Consider subscribing if you want to keep up to date with the new things coming to the channel.

RotoRex Channel Trailer - Design Build Test Fly! (0 min 36 sec)

Posted by RotoRex | Apr 06, 2016 @ 12:40 PM | 4,030 Views
Revolving Selfie Stick with QAV250 FPV Racing Quad (1 min 15 sec)

The Idea
Ever since I saw the video of an rc plane flying with two keychain cameras revolving around it as it flew, I have always wanted to do something similar. A few weeks ago my friends and I were chatting about this and we came up with the crazy idea to put it onto one of our Lumenier QAV250s. So I designed a 3D printed mount that fit onto the QAV250 and allowed two RunCam 2s to spin freely around the copter.

Flying and Modification
After the first test flights we noticed that it didnít spin very much. So I took a Ping-Pong ball and split it in half and mounted the halves to the ends of the arms. Then the mount spun way to fast! It was crazy looking in the air and the video made everyone who watched it sick to their stomachs. So we moved the Ping-Pong balls in toward the center gradually and got it to spin at a more acceptable speed.

The Mount
The 3D printed mount is based around two bearings and a shaft that fits inside the bearings. The bearings and the shaft were obtained from (links below). On the shaft mounted a simple piece that holds two carbon fiber arms out at 20 degrees. Overall the system is silky smooth and spins even better than I first imagined it would.

...Continue Reading
Posted by RotoRex | Apr 03, 2016 @ 09:39 AM | 13,549 Views
I wanted to have a larger battery for my FatSharks so that I didnít have to charge them as often and not worry so much about accidently forgetting to turn them off while changing batteries. To do this I made a 2 cell lithium ion (Li-Ion) battery with Panasonic NCR18650B cells. The completed battery has a capacity of 3200 mAh and is roughly the same size and weight as the FatShark 1800 mAh LiPo. The higher energy density of the Li-Ions does come at a cost of not being able to output as much current as a LiPo (2C max continuous). The low discharge rating is not a problem though when powering the FatShark goggles. Below I have included some pictures of the build and a schematic to help you make your own Li-Ion battery for your FatSharks.

NCR18650B Cells:
Posted by RotoRex | May 20, 2013 @ 05:33 PM | 4,542 Views
Put together some shots that I have taken over the past 9 months.

Rc Flight Montage 2 (4 min 13 sec)

Posted by RotoRex | Sep 14, 2012 @ 08:20 AM | 5,173 Views
I sliced together some of the best shots I have taken with my scratch built plane. Hope you enjoy. Make sure to watch in HD.

Rc Flight Montage (2 min 7 sec)

Posted by RotoRex | Aug 24, 2012 @ 07:36 AM | 5,417 Views
After the not so great success with with my scratch built flying wing, I decided to build something else. Due to the fact that I live on a college campus, it is really hard to find time and space to fly. So I decided I wanted to build a smaller more portable plane and this is what I came up with.

It has a 3 foot wingspan. Uses a Hacker A30-22sV2 motor, 30 amp e-flite esc, 2100 mah 3 cell Hyperion battery, hextronic 9 gram servos, carbon fiber tail boom, and balsa wood construction.

Overall, it flies very well. It does pitch up a little with throttle, that was fixed via some mixing. I might try and add in some down thrust later. I am very pleased with how this plane turned out!
Posted by RotoRex | Jan 03, 2012 @ 01:08 PM | 5,365 Views
Here is a video of me building my first flying wing. I have done a few glide tests and the plane flies! I still need a motor and then it will be finished.

Make sure to watch the video in 720p. Enjoy!

Flying Wing Time Lapse Build (6 min 12 sec)

Posted by RotoRex | May 09, 2011 @ 02:52 PM | 5,786 Views
The inspiration for this plane came from a desire to take aerial videos with a forward facing view that didnít have a propeller in the shot. After a few days of thinking, a design finally came to me and I then modeled the plane in Google Sketchup. The construction time for the plane was approximately a month.

The plane has a wingspan of 64 inches and weighs 3 pounds 10 ounces with the battery. The plane uses an E-flite 15e motor and a 30 amp speed controller and carries a 3200mah 3s battery pack. The plane has five channels: elevator, rudder, aileron, throttle, and flaps.

The first flight was a success! The plane only needed a little bit of aileron trim. Besides that it flew perfectly. I also performed a few flights with a camera mounted on the front of the plane. The video turned out ok, but I need to get a better video camera due to the fact that the video quality of my current camera is not up to the quality standards that I would like.

I also came up with a name for my aircraft. I call it the BX-1 Surveyor. B for the first initial of my last name, X for experimental, 1 because it is the first plane that I have ever built and Surveyor because the plane is designed to carry a camera.

If you would like more info on the plane, feel free to contact me....Continue Reading
Posted by RotoRex | Dec 05, 2010 @ 10:16 PM | 6,832 Views
I am currently a student at the University of Michigan and am currently enrolled in an intro to aerospace engineering class. The final project for this class is building a RC blimp and competing with it.

Eight teams, consisting of five people, were given two months to build and test a blimp that would be worthy for the competition. We had several restrictions on our blimp construction. We could only use two motors, three servos and 10 volts of power. The blimp also had to fit in a small enclosure and have a mass of less than one kilogram. All of the blimps had a balsa or bass wood gondola structure and utilized a lightweight polymeric membrane material for our envelopes.

The competition consisted of a speed and maneuverability test. The speed test was a simple down and back course that was a total of approximately 40 meters long. For the maneuverability test, we were required to fly under a laser and use a video camera to get an image of a box on a ledge and then race back to the start finish line. We then had to count how many objects were in this box.

My team took first place in both the speed and maneuverability courses at the competition. Here are some pictures of our construction and the competition....Continue Reading