Recent content by nburo

Thank you, but I think one of your 6 equations might be dependent of the others. (equation 6, I think)

F, H and J are fixed. I'm studying this particular case.

I get why IB = IC, but not the IB = IC = 2r

Here you go.

I must admit I am very interested by your solution. I'm looking forward for more hints you might have. Thanks to both of you for taking your time. It's really appreciated.

Oh well, thank you!

I misspelled theta, sorry. You might want to ignore them, if they are not necessary (sorry for the confusion). They might become handy later on, when this problem is solved. The context of this problem is related to pool/billiards. To make long story short, A is the ball you want to pot...

"Simple" geometry problem Hello everyone, I need your help in this "simple" geometry problem. I need to find the delta angle, knowing everything else given into the image (see attachment). It might even not be possible at all, for all I know. I've tried very hard, but I still have no...

Wow thanks guys! Your responses are very interesting and useful! Unfortunately, I don't really know much about the Runge-Kutta method =/

Thanks, but ok, le's say I decomposed it in 3 differential equations. Here I'll have : \frac{d}{dt}\theta_1(t) = F(\theta_1(t), \theta_2(t), \theta_3(t) ) \frac{d}{dt}\theta_2(t) = F(\theta_1(t), \theta_2(t), \theta_3(t) ) \frac{d}{dt}\theta_3(t) = F(\theta_1(t), \theta_2(t), \theta_3(t) )...

Hello everyone, I have the following differential equation : \dot{\theta}(t) = \omega(t) - \frac{1}{2}\theta(t)\times\omega(t) + \frac{1}{\Vert\theta(t)\Vert^2}\left(1-\frac{\Vert\theta(t)\Vert}{2}cot\frac{\Vert\theta(t)\Vert}{2}\right)\theta(t)\times[\theta(t)\times\omega(t)] where...

Thank you D H. In my problem, I need to rotate, not to transform, i.e. every equation must be in a global/fixed frame. Which notation should I use?

WHAT? You know that? :biggrin: WOW Thks, but I already knew =) I was too lazy to type it, that's why :P I use LaTeX every at work. It's a so powerful tool!

You're one quaternion beast! :wink: Before using our new equation, my research boss told me to do something. David Baraff published some article in Siggraph '97. He developped a proof that even when û(t) is not constant, a quaternion time derivative can be expressed this way ...

Haha =) I get it, sorry =P Also, with B = [cosφ/2, êsinφ/2]A, does that mean I can simply substitute B by that in my main interpolation equation? What about my time substitution in interpolation? Is it alright? :cool: