The history of flight goes back over 100 years, but until recently, the basic types of aircraft hadn't changed much. The Mavic Pro is a quadcopter, a totally new kind of aircraft. It has many advantages over traditional aircraft, and a few disadvantages as well.
The main advantages of the quad are its agility and its ability to be precisely positioned. This makes it ideal as a camera platform. The main disadvantage is that it's terribly inefficient, with short flight times. It can't be scaled up to compete with commercial aircraft.
Airplanes have wings and flaps. They're very good at going from point A to point B, and that's about it. Helicopters are more agile, can hover, and have been used as camera platforms for years. Think of those breathtaking scenes from Lawrence of Arabia, or car chases, or a view of the city at night. But helicopters are expensive to operate and they can't go just anywhere. They're agile, but they can't do things like easily moving sideways or being able to be programmed in advance.
Another problem with helicopters is that they are mechanically complex. The main rotor has a series of mechanical linkages that continuously varies the pitch of the rotor's individual blades. This part requires lots of maintenance, adding to the cost of operation.
Nevertheless, helicopters will still be used by the movies for their advantages, like being able to carry heavy cameras, or staying airborne for long periods of time.
A quadcopter can duplicate the helicopter's moves, but with a very big difference. Flying a helicopter to do these sorts of moves is very difficult and requires years of training and practice. Quadcopters like the Mavic have an onboard computer that takes most of the skill out of these maneuvers and presents a beautifully simple interface to the flyer.
Compared to a helicopter, a quadcopter is quite simple. No tail rotors, or adjustable-pitch rotors. All it has are the four motors and the four propellers, arranged roughly in a square. The only thing the quad's little brain can do is change the individual speed of each of the propellers. By doing this one simple thing, it can set the quad in the most complex of maneuvers. Let's see how that works.
Imagine the quadcopter hovering motionless in the air. All four motors running at about the same speed. Now imagine that the onboard control system raises the speed on the two motors at the rear of the craft. The back of the quad now has more lift and it raises up and starts to move forward. Speed up the front motors instead and the copter moves backwards. The same thing for moving side to side. Or even for moving at an angle by speeding up one of the motors at the corner.
These forward/backward/sideward moves are all handled by the right joystick. But, thanks to the interface, you don't have to think about individual motors going faster or slower. All you do is push the joystick in the direction you want the quad to fly.
Pushing the left joystick forward or backward causes the quadcopter to go straight up or down. It does this by speeding up or slowing down all four motors at the same time.
Pushing the left joystick to the left or right causes the quadcopter to turn on its axis. The theory behind how it can do this with just its four untiltable motors is left as an exercise for the student.
All the time that the quadcopter is in flight, even when it's just hovering, the flight control system has to make sure that the craft stays stable, without bouncing around too much. This is done with an accelerometer that feeds into the control system, with the same sort of inputs as the optical image stabilizer in your camera, with much the same effect.
It's impossible for the flight control system to smooth out all the nastiness as the quad goes zipping around. This is where the three-axis gimbal that holds the camera come into play. The three motors in the gimbal can pan, tilt, and roll the camera so that it always stays on target. I've seen the Mavic bouncing around during flight, especially during a landing. But the videos that I shot were always rock-solid.
The beauty of this is that all of this technology has been used to present a very simple interface so that you can concentrate on your photography instead of the nastiness that a pilot would see while putting an aircraft through complex maneuvers.
I hope that this has helped to explain how the Mavic, and similar multi-rotor craft, manage to leverage a lot of technology to make the ideal camera platform.
Copyright 1958-2017 Tony & Marilyn Karp