kinematics library?

[Ares2600]

I'm more of a software engineer than a physicist, so I'm hoping someone here might be able to point me in the right direction. I'm developing some software that could benefit greatly from some kinematics analysis function and I can't seem to figure out exactly what to search for.

What I've got is a series of xyz coordinates sampled at fixed intervals and I'm hoping to programmatically get a series of velocity/acceleration numbers from those coordinates. Probably quite simple to those here who are more well versed in physics. Specifically I'm hoping to find the velocity of the object and the acceleration forces that are acting upon it at that particular time. I'm tracking the dynamics of a moving car and want to be able to get information regarding it's acceleration/braking as well as turning.

So two questions I guess.. Do you know of any software libraries that I might be able to utilize in my project that can accept this sort of information? (I'm trying to trigger this from php or java, but I can make anything work I suppose) Or secondly, is there a set of equations you could point me to that I could implement programmatically? (this isn't much of a problem.. calculation in software I can do, as long as I know the equations).

Thanks for any help or ideas you can shoot my way.

 

[MercenaryForHire]

Open Dynamics Engine?

- M4H

 

[Ares2600]

Yeah that kept popping up in my searches too.. I've read through the manual and faqs and it seems to simulate things more than give feedback on a recorded object, but it's possible that some support libraries within it are up to the task. I posted on their boards.. Still hoping there's something more suited to the task though.

 

[Matthias99]

I don't have a nice package to tell you about, unfortunately. But if you want to calculate things yourself -- velocity is just distance/time, and acceleration is velocity/time (so take your current and previous velocity values and see how quickly it is changing).

If, say, you have samples every 1/10s, and at time 0 you're at <0, 0, 0> and at time 0.1 you're at <1, 1, 1> -- your average velocity there is ((<1, 1, 1> - <0, 0, 0>) / 0.1) = <10, 10, 10>. If you want a nondimensional "speed", it's sqrt(x^2 + y^2 + z^2), or in this case sqrt(300) ~= 17.3 units/second.

For acceleration do the same thing but subtract between velocities rather than positions.

Things get trickier if you want rotational velocity/acceleration as well. You have to convert to something like polar coordinates.