Gadgets

Parrot AR.Drone Teardown

Removing the motherboard from the Parrot AR.Drone
Removing the motherboard

We’ve had the Parrot AR.Drone — an iPhone-controlled, indoor or out, four-propeller rotorcraft — at the iFixit offices for months. We bought it for a teardown, but we just couldn’t stop playing with the flying bugger long enough to take it apart. Until now.

The AR.Drone is earth-shattering. It has blown away every drone expert we’ve talked to. It’s not just a toy: it’s a phenomenal piece of engineering that manages to solve some very difficult software problems in order to take flight. Hidden beneath the foam fascia lies some very sophisticated electronics, all of which makes flying the quadricopter very seamless. We were quite interested in seeing exactly what components Parrot used to make their awesome flying device.

We gave the AR.Drone a 9 out of 10 on our repairability scale. Tons of replacement parts are available directly from Parrot’s website, in addition to videos for common repairs for the device. We’ve never seen another consumer electronics device with this much advance planning for user repair. That’s a good thing too, since just about everyone we’ve let fly our drone has crashed it. Flying is hard, even with an iPhone!

Teardown highlights:

  • Each propeller assembly is made up of the propeller blade, gear, motor and motor controller board. These are not your run-of-the-mill propellers. The design team behind these won a micro drone design contest put on by the French Army. The propellers spin in different directions depending on the side they are mounted on, and are marked either C (clockwise) or A (anti-clockwise).
  • The propeller blade and gear are held in place by a small circlip on a stainless steel shaft. Parrot sells a special circlip removal tool, but we opted for a pick we had laying around the office. We learned very quickly that if you’re not careful, the little circlips are also capable of flight.
  • Each brushless motor runs at 28,000 RPM while the AR.Drone is hovering, and ramp up to a whopping 41,400 RPM during full acceleration! The speed of the motor is managed by the electronic controller, which includes an 8-bit microcontroller and a 10-bit ADC.
  • Much of the AR.Drone’s body is made of expanded polypropylene (EPP), a common substance that is both extremely light and easily manufactured into complex shapes. We like to call it by its scientific name, “foam.”
  • The two large mesh cylinders make up the ultrasound altimeter, which stabilizes the quadricopter within 6 meters of the ground.
  • The navigation board, which attaches to the motherboard via eight pins, contains a Microchip PIC24HJ16GP304 40MHZ 16-bit microprocessor in addition to a MEMS gyroscope (the Invensense IDG 500).
  • The motherboard itself hosts a Parrot 6 ARM9 468 MHz processor, ROCm Atheros AR6102G-BM2D b/g Wi-Fi module, a couple of Micron chips, and a vertical camera.
  • The battery is a 1000mAh, 11.V lithium unit that detaches easily from the quadricopter. It lasts about ten minutes. There’s a second connector on the battery for balance charging, which ensures that each of the three battery cells charges equally, thus optimizing capacity and prolonging battery life. The battery also contains a protection circuit module, which prevents it from discharging too rapidly, over charging, or short circuiting.
  • The 93 degree front-facing wide-angle camera can stream its video and images directly to your iPhone, iPad, or iPod Touch. With a resolution of 640×480 pixels, we doubt anyone will be filming HD movies with the AR.Drone’s camera.
Removing a motor from the Parrot AR.Drone
Removing one of the motors
Parrot AR.Drone teardown parts
Final layout