Start here 9 min
Sizing a multirotor from scratch
How weight, thrust, propeller, ESC and battery are chosen, in the order they actually have to be chosen.
5 rules of thumb
Groundschool // Learn it before you buy it
Groundschool
A component database tells you which part. It assumes you already know which kind of part, and why, and which number to compare. These are the explanations that come first.
Written for people building their first aircraft or robot, and for anyone who has been handed a spreadsheet of motors and told to pick one.
The course
In order. Each one assumes the last.
Motors 8 min
Reading a motor datasheet
What KV, stator size, thrust tables and g/W actually tell you, and which figures to distrust.
4 rules of thumb
Power 7 min
Batteries: mAh is the wrong number
Why watt-hours and Wh/kg decide endurance, what a C rating is really telling you, and how to size a pack.
5 rules of thumb
Power 6 min
ESCs, and what the amp rating means
Continuous against burst, why cell count is a hard limit, and what firmware and BEC actually change.
5 rules of thumb
Actuation 6 min
Servos: torque, speed and splines
What kg.cm means, how to work out the torque you need, and why the horn from your last servo will not fit.
5 rules of thumb
Autonomy 7 min
Sensors and compute for autonomy
What a vehicle needs to know about itself, what it needs to know about the world, and what it takes to work it out.
5 rules of thumb
Then go and choose something
Every article links into the catalogue at the point it becomes relevant, filtered to the parts it was talking about.