I had been thinking about building a lifesize quadrotor helicopter in the vain of my little blade mqx and I had a look to see if anyone had done it, and came up with this video. The team has publicly displayed this at the 2012 German Air Show and received Lindberg award for innovation. There is a couple of other images if you search this subject, but this is the only one I know that has been built.
This design uses 16 2 kilowatt motors. I am unsure of the other specifics of the vehicle other than estimated weight at 170kgs.
I believe that this type of design would be possible in a quadrotor configuration. By lowering the centre of gravity to the intersection of the chassis arms the vehicle would be more stable. By reducing the amount of motors the chance of failure decreases.
The Quadrotor would also offer a greater propeller thrust area. There is a lot of estimation involved in calculating the specifications of downward force required for sufficient lift. After some initial consideration my proposal is as follows..
PERFORMANCE and Specification GOALS:
A quadrotor vehicle capable of 1000 feet altitude and 100knots
48kw continuous,120kw burst
300kg gross weight
Battery pack capable of 30ish minutes flight time (giving 80km range)
Aluminium Frame/chassis + Carbon Fibre Fuselage and Fan shrouds
Under 5meters total diameter.
Stability software for safety and easier learning curve.
Driver position would be slung below the level of the rotors with head at a level just above, keeping CoG neutral. Driver also to be enclosed in high rigidity, enclosed shell in the middle of the four rotors (aka AR drone).
Premilinary sketch of the chassis i produced on sketchup is of dodgy quality but my main computer is being rebuilt so I have no Solidworks at the moment. IThe cockpit chassis is obviously unfinished, ill get to it when i have solidwords back. It should give a vague idea though.
There is about 18 metres of aluminium there worth about $1200 and about another 18m to complete the cockpit and supports, meaning around $2500 of materials for the chassis.
The sensor required by the software to level the aircraft could be the ARM UM6-LT Orientation Sensor (IMU) Autopilot w/ Arduino. It is around $150,
For motors, I am considering a pair of these kits:
These are from kellycontrollers, they are rated 12kw continous (150a) and 30k max. Retail at $2700 meaning 5400 for chargers,motors and controllers.
The controller is a 500amp kellycontrollers unit and the motor is the Mars ME0913.
For batteries Im looking at
24 packs will be required for the 288v. Hopefully these will deliver close to half an hour of flight. Unless under unusual circumstances, the system should run at under 150 amps which should mean a good battery life. Control input would have to be perfect and I thought something like this may fit the job when modified ($200)
There will be many other parts needed, such as instruments, software, seat, fibreglass or carbon-fiber cockpit and fanshrouds etc... I was thinking of building a naked prototype, as the cockpit/fanshroud design and fabrication could well be the most espensive part of the project.
If you add the costs already calculated you can see that this is no small undertaking and without any expertise in many of the areas required to complete this project (especially electrical systems) I'm wondering about what you guys think about the viability of this....
Major Concerns would be:
The performance of self levelling software.
Total Weight. (65kg Battery pack. 80kg for motors/controllers. Frame estimate 40kg). Only leaves 115kg for everything else...
Cockpit rigity and crash avoidance/systems.