Re: [simspark-devel] Simspark Todo

[Sander v. D. <sgv...@gm...>]

Hey,

2008/5/18 Feng Xue <hen...@ma...>:

>     I'm not familiar with the motor parameters described in
> NaoHardWareSpec.zip. So please check rsg/agent/nao/hingejoint.rsg,
> is the new joint speed limit reasonable?
>

These look good (beware: I have not been able to actually test them yet, I
just looked at the numbers :) ), though to be complete, why not set the
correct max velocity on each joint as described in the documentation instead
of using the maximum for each? Besides that, maybe setting these maximum
velocities are enough for now, but we can also set the setMaxMotorForce.
Since ODE tries to achieve the motor velocities as fast as possible, without
reasonable torque values there can still be unnatural accelerations. As far
as I can tell from ODE documentation you can use the stall/nominal torque in
Nm directly from the documentation as arguments for setMaxMotorForce now our
model's size is in actual meters.

    And, I think there is another thing todo now. The collision
> between the two thighs, and the collision between the torso and the
> lower arm. With joint angle limit, we also have some bug state.
>

About the collisions, I think the disableInnerCollision parameter is a hack
that works now, but we shouldn't need it. The problem is that the
geometries/colliders in the bodyparts overlap in valid positions, because
the primitive boxes and spheres don't match the more complex visuals. Also
the double hip construction means two bodies at the same position.. why is
chosen for this instead of a universal joint in the hip?

It is possible in ODE to have mesh geometries. In theory it should be
possible to use the mesh data in the .obj files to create this. Though for
now it might be possible to try to use multiple smaller colliders and
TransformColliders to more closely match the body parts.

Sander