Budgetcopter

Not surprisingly the X525 frame has sold out already, and the next best price I could find it for was 150% the price. So while I wait for it to be restocked, I'm researching the best combination of components to make a stable quadcopter for the minimum cost. Obviously a scratchbuilt frame would be cheapest, but considering what you can get off the shelf for very little money and the importance of a rigid frame, I have gone for a pre-built frame.

I chose the x525 frame which looks excellent quality. I have seen another, which is better...
The Turnigy Talon V2 is similar size but all carbon fibre chassis, and thus weighs in at 280g vs the x525's 385g. That's over 100g difference.
However - it costs twice as much. Decisions decisions...

I will try the 39g FC2822 motors, as I have an FC2805 that has run well for over a year. Should get 700g+ thrust on a 10x4.7 at 14A, for $6 per motor. That gives 2.8kg max thrust on a 1kg setup, so 9x5 props could work as well.


Parts for 'Budgetcopter 1' will be:

1 x X525 V3 Glass Fiber Quadcopter frame 600mm              $21.77
4 x FC2822 - FC 28-22 Brushless Outrunner 1200kv             $27.96
4 x TURNIGY Plush 25amp Speed Controller                       $47.24
1 x HobbyKing Multi-Rotor Control Board V3. Atmega328     $19.99
Total $117
(With the Talon frame it would be $145)

I'll add a build log as I go.

How much beer would a multicopter lift if a multicopter could lift beer?

Now here is a fun idea. Hobbyking's Multirotor beerlift 2012 competition! You can win Turnigy Talon Carbon Fiber Quadcopter Frames and a ton of store credit. Hopefully I can get mine ready in time. This should both be instructional and hilarious.

Who's taking a copter to SEFF 2012?

If you've forgotten SEFF 2012 is coming up on April 22-25, this is a reminder - REGISTRATION CLOSES TODAY, April 1. Go Here to register.

What is SEFF? ... Well, it's arguably the most fun weekend a flyer can have, and if you've never gone it's something you really must experience. This video probably describes it best:

X525 Foldable Quadcopter Frame

After looking around for the parts for my new Quad, I think I may have found my Quad frame here. Fibreglass / Aluminium alloy, shock absorbing spring loaded landing claws, 600mm - perfect.

Even better, it's only $22 ! Since my entire RC budget will be going toward this project for now, I'd like to keep costs down.
It looks good, appears quite rigid and also folds for easy transport. Now I will source the electronics and report back. I want to see how inexpensively I can build this while still making it fly well, and I think this frame is a good start.

Later I will upgrade to a high level controller board and eventually add FPV capability! But first, we have to make it fly well, and I will document the process as I go.

Quadcopter History 101

I would like to correct my statement last week that we have recently achieved manned flight with Multicopters. This was achieved nearly 100 years ago!

The de Bothezat helicopter was an experimental quadrotor helicopter built for the United States Army Air Service by George de Bothezat in the early 1920s, and was said at the time to be the first successful helicopter. Although its massive six-bladed rotors allowed the craft to successfully fly, it suffered from complexity, control difficulties, and high pilot workload, and was reportedly only capable of forwards flight in a favorable wind. The Army canceled the program in 1924, and the aircraft was scrapped.
Working almost entirely without models or wind tunnels, de Bothezat's helicopter was completed in December of 1922. Featuring four six-bladed rotors at the end of massive, bridge-like girders braced with piano wire, the craft had two vertical propellers – "steering airscrews" – for lateral control, and two additional three-bladed propellers mounted horizontally above the Le Rhône engine to provide airflow for cooling. The rotors tilted in towards the craft's center at an angle of five degrees, enhancing stability. The aircraft had two control wheels, a control stick, and foot pedals for control, with each rotor featuring variable-pitch blades for individual collective control.
After initial ground testing, the de Bothezat machine made its first flight on 18 December 1922, piloted by Major T.H. Bane of the US Army Engineering Division, and hovering to a height of 1.8 m (6 feet). The propellers for lateral control were soon found useless and removed. Its original Le Rhône engine proved underpowered and was replaced by a Bentley rotary type. Over the next year, over one hundred flights were made, carrying up to four passengers in addition to its pilot, and setting records for duration (2 minutes 45 seconds) and altitude - 9.1 m (30 feet) for helicopter flight.

I do believe if he just had a gyro /accelerometer based control board (now available for about a hundred bucks), I'd be driving to work in a quadcopter tomorrow.

What is a MultiCopter?

So what is a multicopter, and why are they cool?


A multicopter is a small remote control aircraft with two or more rotors. Control of vehicle motion is achieved by varying the relative speed of each rotor to change the thrust and torque produced by each, and by doing this they can climb, spin and roll. Even perform back flips.
Due to their ease of construction and the huge drop in price of RC gear recently, multirotor aircraft have become popular in radio control aircraft projects. Quadcopter, hexacopter and octocopter are frequently used to refer to 4, 6 and 8 propellers.
Radio controlled multirotors are increasingly used as an inexpensive way to create aerial photography and videos. Or just to experiment and have fun flying something you created. FPV has become very popular, where the pilot has a live First Person View through a small camera mounted on the aircraft, viewed on a screen, laptop or goggles. This provides a virtual reality experience of actually flying the aircraft! They are something different and challenging. Plus they look like a UFO.

In the next update I will start to look into how you can build one at home, what the best parts are and how they work. But for now here is a video of some FPV flight (I highly recommend going fullscreen) :

Swarming Quads

A great TED talk on the uses for multi copters in the real world, and how the technology is advancing. Most of this kind of progress has been made at universities and by the multi copter community.