[ODE] Initial conditions problem

[Bram Stolk]

Thomas Paviot wrote:
> Hello,
> 
> A human being throw a stone far away : i want to simulate the movement 
> of the stone. When the stone leave the human's hand, the velocity vector 
> is 1m/s with an angle of 45° with gravity vector.
> 
> Before starting an ODE simulation, at initial time, all velocities are 
> equal to 0.0. Is it possible to apply initial velocity to a joint (or a 
> body) before starting simulation? It seems there is no builtin function 
> to do that.

>From the manual, section 6.2:

void dBodySetLinearVel  (dBodyID, dReal x, dReal y, dReal z);

These functions set and get the position, rotation, linear and angular velocity
of the body. After setting a group of bodies, the outcome of the simulation is
undefined if the new configuration is inconsistent with the joints/constraints
that are present.

I would try that one.
Also, look at the test_crash example, where a cannonball is fired
with initial speed.

A physically correct specification would probably be that you specify
a force, and a duration that this force acts upon the body.

 Bram

> 
> Anyway, do you have any tip to go around the problem?
> 
> Thomas
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-- 
Bram Stolk, VR Engineer SARA, Amsterdam.   tel +31 20 592 3000

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