[Animats]

Gazebo with Mike Sherman's physics engine might be good enough. DARPA paid to get a decent physics engine into Gazebo; the ones from games were never quite right.

[Nican]

Which physics engine is that? ODE?

[Animats]

Stanford (Simbody) is the new one.

The game engines don't do complex friction, as between gripper and target or foot and ground, very well.