Experimental Momentum Cancelling Turned On
In the above flight, Arducopter 2.3 is being used with stock PID, basically no tuning at all. The INSTANT_PWM, is enabled. The propellers are not balanced, and nicked up, from rough flying. The framed use is my 3D Printed FireFly Mark One. As you can see, I'm purposely flying it really hard. Wish I could have recorded the stick movements. Basically, I am pushing the stick in one direction, and then pushing it back to neutral, and then past it. The feeling is that the quad is anticipating the direction change, and slowing down ahead of my movement, which is the type of behaviour that I'm expecting from the code.
Stock Arducopter 2.3 with No Momentum Cancelling
The above flight, is using the same code at the first, except the experimental Momentum Cancelling code is turned off. Same as the first flight, stock PIDs, INSTANT_PWM is turned on, as well. Again absolutely no tuning. What I notice is that with no Momentum Cancelling, it's much harder to change directions. The feeling of the quad responding ahead of the direction change is just not there, so I'm just not able to flick it around like with the experimental code.
Description of Momentum Cancelling
As you roll or pitch a quad, it will start moving in the direction of the stick input. It will continue in the direction of roll or pitch until you use input the roll or pitch in the opposite direction to counteract that motion. If the quad was a car, the equivalence would be applying the brakes to stop it. That's manual Momentum Cancellation.
The code that I've added does this automatically, when the joystick goes back to the neutral centre position. It's really that simple a concept. It's not rocket science. This very experimental code currently applies 2.5 degrees of pitch or roll, whenever the stick goes back to centre. This is in fact, quite small. Much more work needs to be done before it can be release to the general public.
The Ultimate Goal
I have a goal for the end game of this code. Ultimately, if I'm successful, my quad will fly like a hummingbird or a bee instead of a regular bird, or airplane. Many things need to be added to enable this to happen.
Details on building the Firefly Mark One Quad are available in my previous blog.
Of course the feel of a quad is a very subjective concept. Would love to hear what people think of the comparison videos.