[lmm]

The multi-rotor drones are basically uncontrollable without computers; you need a reasonably powerful processor, which in turn means a fairly high-capacity battery. I think a lot of the innovation has come from mobile phone tech; there's now a lot more demand for small, light, high-performance processors, batteries and cameras, and so while much of the tech is not really new it's a lot more available to hobbyists than it was a few years ago.

[cscheid]

The set of (say) 4 motors consumes much more power than the on-board computers. Brushless controllers these days handle 20 amps at around 5 volts for a total wattage of 400W(!) . The on-board computer power doesn't even count.

Of course, you're right that powerful computers are needed. But it's more about miniaturization for weight purposes.

[fh973]

Most fly with 8-bit Arduinos actually. Their power consumption is nil compared to the brushless motors.

[Florin_Andrei]

> The multi-rotor drones are basically uncontrollable without computers; you need a reasonably powerful processor

True.

> which in turn means a fairly high-capacity battery.

Not true.

A microcontroller CPU is good enough. Take a look at the KK2.1 flight controller.

https://www.hobbyking.com/hobbyking/store/__49254__Hobbyking...

Its brain is an ATmega644, which only requires 240µA @ 1.8V, 1MHz, according to the spec sheet.

http://www.atmel.com/devices/atmega644.aspx

You do need energy-dense batteries, but all that energy goes into the rotors.