Justa learning to fly
Learning to fly
After getting home and replacing a prop (and ordering shitloads more), it was time to start taking flying lessons.
The KK2.0 has a nice feature called 'auto-level' which will keep the copter mostly level when no other inputs are being sent to it. I soon found out that i had to adjust some P/I gains down to prevent the copter from oscillating when in that mode. Currently, it flies quite nice with it enabled.
Auto-level is rather awesome in that it keeps the copter from trying to fall over all the time. It is rather like trying to balance a broom on your fingertip, otherwise. You constantly need to adjust to prevent it from going somewhere you don't want. This is true for auto-level flight, too..only just not as much. The challenges are as such:
Controlling Height
This is first thing to work on. It's already exciting/nerve-wracking to watch your propellers spin up and your aircraft trying to get off the ground... Will it work ? Will it fly properly ? Nothing is preventing it from crashing and burning to the ground EXCEPT YOUR NON-EXISTENT FLYING SKILLS.... Great.
The issue here, though, is to get all four legs off the floor as simultaneously as possible. If one sticks to the ground while the others are airborn, the aircraft will start to turn around that one leg, changing your orientation and require you to adjust that soon after takeoff.
The first flight of a new copter can be challenging for the above reasons, but once you know that the device is basically flight-worthy, it's best to simply pull it off the floor as quick as possible without giving TOO much impulse... because....
... once you're airborne , you're "loose" and subject to all kinds of effects.
When flying low ( 50CM or less) you are subject to extra lift generated by the wind generated by your propellers hitting the ground and reflecting back up, giving your copter an extra push up. Your copter gets pushed up higher than that point , loses the extra lift, descends again.. gets lift, goes up, loses lift, descends...and there you continue oscillating, unless you compensate just enough for this to stop.
When adding thrust, it's easy enough to see how much you need to add to increase the rate of climb. When removing thrust, this isnt always as clear. Going up is kinda a linear thing. Going down is more of a logarithmic thing. Soon gravity starts pulling you down faster and faster and before you know it, you have to compensate to prevent your aircraft from hitting the floor hard. Sometimes, you need to REALLY hit the throttle to prevent it from smacking down hard. If you do, be careful to also RELEASE the throttle quickly enough when it's clear you're rising, or else you'll find yourself flying at 30 meters height, giving you an impulse to quickly release the throttle.. and so on.. and so on.
Another challenge that you'll deal with soon enough is the reduction of lift when making other maneuvers.. When banking forwards/backwards or left/right, you will also loose some height. This is also partly true for spinning around your axis. So in all these cases you need to add a little of throttle to compensate.
