66 replies to this topic

[lebrett]

Mat Wellington, on 01 March 2012 - 07:50 AM, said:

issue is the mass/gyro forces of the prop assembly are large compared to the mass/distance from props

Would you please explain a bit further, I don't get it .

Is it a problem of slowness  ?

[Adverse Effects]

lebrett

try to push a spinning top over and get it to stay laying down

it keeps trying to stay where it is and not move

i hope that translates in french


essayer de pousser une toupie et d'obtenir plus il rester fixant

il continue d'essayer de rester là où il est et ne pas bouger

Edited by Adverse Effects, 01 March 2012 - 09:46 AM.

[Adverse Effects]

mat i think the trick is going to be more computer power to control the speed of the movement of the gimble

maby even small control veins to help

Edited by Adverse Effects, 01 March 2012 - 09:50 AM.

[lebrett]

Adverse, I understood the gyroscopic effect.


I got it : the issue is the  moment of inertia (wrong translation so, slowness isn't inertia )

Technic english words are differents, I have to read the english wiki about stability.Forgive me for my bad english

Edited by lebrett, 01 March 2012 - 12:19 PM.

[Adverse Effects]

the force it takes to move it because of its mass or gyroscopic stability

inertia = in outer space throw a ball and it keeps going till it hits something


if this is annoying just tell me to shut up

i have a reading and writeing problem my self (dyslexic)

Edited by Adverse Effects, 01 March 2012 - 02:39 PM.

[lebrett]

It's ok


I'm concerned with all theses gyroscopic/mass/inertia/moment involving forces.

I will do some tests tomorrow with my birotor's servo+motor mechanism, trying to set the lightest and simplest thrust vectoring design.

[Mat Wellington]

Haha, here is a well written explanation for what I have experianced between props above and props below the CG

http://www.rcgroups....531&postcount=4

This causes trouble when the CG is below the nacelle, causing an initial tilt that is the opposite direction than the intended one, while works better if the CG is above the nacelles