Revision history [back]

What's happening is your robot model is "exploding": see here, here, and here for what I mean by exploding.

Essentially, what's happening is the model (the PR2 in your case) is colliding with something (either itself or the plane since its and empty world) and the physics engine is not updating fast enough to catch the collision. The models wind up slightly inside of each other and, in an effort to fix the collision, the physics engine pushes the two models away from each other (sometimes at VERY high speeds making the mode "explode). That explains why the PR2 is disappearing. When this happens, the physics engine essentially stop working properly and causes the error message you are seeing. Try modifying your world file with the parameters defined here. In particular, contact_max_correcting_vel defaults at 100 and can be lowered to a smaller value (e.g., 1) to slow down this violent collision correction. You can also update the update rate of the physics engine (iters).