Helicopters, Tricopters and Quadcopters

[redpoint5]

For some reason I have recently been obsessed with the idea of aerial video and photography, and it got me thinking about what would be the ideal setup for me. Helicopters seem the logical choice since they are way more power efficient, having fewer motors and a larger lifting disc. For some reason they don't seem to be very popular, and I don't see the same gyro stabilization that is utilized on quads. It's beyond me why they wouldn't have similar gyros and automatic systems. If they did, I assume they would be the best platform since adjusting a swash plate is much faster than adjusting rotor speed, and the flight time would be much higher.

It seems the next best thing would be a tricopter since it has 1 fewer rotor for efficiency, and can turn with more agility. I'm tempted to build one myself, but then I see great deals on the DJI Phantom. I like the built in features of the Phantom such as follow me, return to home, position hold, etc, but I don't like that it isn't very modular. I'd like to swap cameras as tech improves along with batteries and such. I also don't appreciate the Apple-like restrictions they place on customers, such as altitude ceilings and such. Let me decide what is acceptable use of the product.

Can a Tricopter be built with some of the same features as the Phantom? I'm handy with electronics, but don't really know what is possible to build. I'd want return to home and position hold at minimum.

I finally got the guts to start flying a Blade CP Pro that a roommate gave to me. Yesterday I hovered for the first time, but lost a tail skid in the process. Lots of fun, I just wish there was more automation available for the platform.

[hamsterpower]

There are a few flaws in your hypotheses. First a helicopter is not really the best camera platform. A helicopter has fewer and slower moving rotors but that leads to more vibration. In small scale (as in not carrying people) the inherent stability and vibration canceling of a quad (or greater) is a benefit.
Another is the misconception of electric motor efficiency. Having more lightly loaded motors is not noticeably worse. At light loads and higher RPM electric motors are more efficient that more heavily loaded or lower RPM (within reason). A tri-rotor is not going to be as maneuverable or stable as a quad. Quads yaw (rotate on axis) by varying the torque of opposing rotors. Tri-rotor will be harder to fly without equal number of opposing rotors. Many remote controlled camera platforms go one further, stepping up to 6 or even 8 rotors.
Where a conventional helicopter wins out is safety. A helicopter can glide without power, where multi-rotor aircraft can not. For carrying people that is a must.
The "Apple" like restrictions on altitude (at least in the US) is a regulation you will be required to comply with whether the computer is in control or a human is piloting the craft. Please leave the higher altitude filming to maned flying platforms and keep the "drones" below 400 feet above the ground (AGL). It's the law.

As far as building your own, anything is possible. The part combinations are endless. From 1/4 pound FPV racing quads to automating full size aircraft.
Hope this helps.

[jamesqf]

Originally Posted by redpoint5

...I assume they would be the best platform since adjusting a swash plate is much faster than adjusting rotor speed...

Not really. Depending on the type of motor used, changing speed could be a matter of milliseconds or less, as the computer just changes the pulse width modulation. And it's simpler, since it's just computer commands over existing circuitry. With a swash plate &c, you need to add the mechanism & actuators.

[botsapper]

Just had the International Drone Expo come through here. The largest UAV trade show. From $10 toys to specialized $100,000 law enforcement versions. It had the latest rotorcrafts, UAV innovations, applications and reveals the development trends of the tech. Some could take drone photos with your smartwatch, with one key control and with voice-control. From beginner, enthusiast and professional grade; aerial photography drives the huge number of multi-rotor companies and technology.

https://www.youtube.com/watch?v=eMn99UIHycM

[freebeard]

www.drone-registration.net/‎

Regulation of drones in the hands of civilian pilots took a big step forward today. The Federal Aviation Administration announced that all units weighing between 0.55 pounds and 55 pounds must be registered by February 19th, 2016. Anyone caught flying without proper registration after that date could face stiff penalties. The FAA says civil penalties include a fine of up to $27,500. Criminal penalties include a fine of up to $250,000 and up to three years in jail.

http://www.theverge.com/2015/12/14/10104996/faa-drone-registration-register-february-19th

Forward? Surely, they mean upward.

[oldtamiyaphile]

Quads have the advantage of (optional) ducted rotors which at least in theory can add massively to efficiency.

E-Flite has their new auto correcting "SAFE" panic button on some of their helis.

Cyclic is faster than changing motor RPM, that's why good helis have cyclic tails in favor of the cheaper/ simpler separate tail motor option. You won't find any pros flying motor driven tails.

[hamsterpower]

Originally Posted by freebeard

www.drone-registration.net/‎


http://www.theverge.com/2015/12/14/10104996/faa-drone-registration-register-february-19th

Forward? Surely, they mean upward.

As a professional pilot I support regulating all aircraft. However the registration measure was negated the very day it took effect, The very first time a fool posted a picture of his certificate on facebook. Anyone can now write that fool's number on the model intending to misbehave with.

[freebeard]

Facespook ruins everything it touches.