Showing posts from October, 2015

How to measure top speeds of multirotors

How fast can your multirotor fly? The simplest solution for this question would probably be to attach a GPS device (tracker / OSD) to your multirotor and to read out the maximum speed.

But hey, this is pretty imprecise...!
GPS devices suffer from measurement noise (e.g. through signal degradation), which becomes problematic on rapidly accelerating objects like our multirotors. More advanced GPS chipsets (e.g. u-blox LEAx) have the option to choose between different filtering modes (e.g. pedestrian, car, airborne), that make some assumptions on the maximum accelerations and movements of the sensor and filter the results accordingly. That will most likely improve the accuracy of the measurements, but still noise might remain. Here is an interesting article on GPS speed measurements, which states that the classical methods to calculate velocities in GPS receivers have an accuracy in the order of a few meters per second, due to significant noise.

I was recently attaching a pretty good GPS …