Thanks, I will have to find my schematics I did in eagle and upload it, but they already are in my posts on the forum, as I built both of those circuits by the help and support of this great forum. They are simply one Arduino board copy and an L293E motor driver with standard components of datasheet, nothing more.
I have D terms now, actually, after filtering angle, currently I get a PID this way:
output= angle * 3 + rate * 2 + angle_integrated * 0.0
I tried a lot, in fact 2 whole days in changing various possible P.I.D. values. Giving even a 0.05 to "I" term introduces wildness: motors start to run fast and never stop. Values of P and D terms other than what above, also introduce wildness.
I think I'd anyway need a reconstruction of a chassis with first designing a 3D model, based on some model I still don't know of! So that at least the body gives me room for applying suggestions: adding weight, removing weight...
Please have a look at where my sensor is. The accelerometer X axis is horizontally placed, toward the forward movement of the machine, and is the only axis of the accelerometer being used (I have a Y axis too).
