Three-dimensional (3D) reconstruction of an object (102) or of an environment (100) can create a digital twin or model of a given environment of a robot (100), or of a robot (102) or portion of a robot, which can enable a robot to learn skills efficiently and safely via simulations. A simulation system simulates peg-in-hole configurations in a mechanical system (100) that includes a cylindrical object (120) and an object body that defines a cylindrical hole.