Abstract: Methods and systems for executing a simulation of a multibody system are described herein. In one broad aspect, there is provided a computer-implemented method for executing a simulation of a multibody system, where a physics-based simulator is used to simulate the multibody system by: partitioning the multibody system into a plurality of subsystems, the multibody system comprising bilateral and unilateral constraints, and a set of interfaces that couple at least two of the subsystems is defined; at each of a plurality of time steps, employing a Schur complement method to compute an effective mass at each interface of the set of interfaces, and solving each of the plurality of subsystems to obtain a plurality of internal impulses.

Abstract: Methods of and systems for executing a simulation of a constrained multi-body system. The method comprises, using a physics engine, simulating the constrained multi-body system, wherein: the constrained multi-body system comprises articulated constraints, the articulated constraints are associated with a geometric stiffness matrix; the geometric stiffness matrix defining a geometric stiffness; a diagonal approximation of the geometric stiffness matrix is generated; and the diagonal approximation is used as part of a stability analysis in which damping is automatically adjusted so that the damping stabilizes the simulation of the constrained multi-body system.

Abstract: Methods and systems for executing a simulation of a multibody system are described herein. In one broad aspect, there is provided a computer-implemented method for executing a simulation of a multibody system, where a physics-based simulator is used to simulate the multibody system by: partitioning the multibody system into a plurality of subsystems, the multibody system comprising bilateral and unilateral constraints, and a set of interfaces that couple at least two of the subsystems is defined; at each of a plurality of time steps, employing a Schur complement method to compute an effective mass at each interface of the set of interfaces, and solving each of the plurality of subsystems to obtain a plurality of internal impulses.

Abstract: Methods of and systems for executing a simulation of a constrained multi-body system. The method comprises, using a physics engine, simulating the constrained multi-body system, wherein: the constrained multi-body system comprises articulated constraints, the articulated constraints are associated with a geometric stiffness matrix; the geometric stiffness matrix defining a geometric stiffness; a diagonal approximation of the geometric stiffness matrix is generated; and the diagonal approximation is used as part of a stability analysis in which damping is automatically adjusted so that the damping stabilizes the simulation of the constrained multi-body system.

Abstract: A parallel jaw robotic gripper and method for operating the gripper to grasp an unknown object are disclosed. The parallel jaw gripper of the present invention includes two pairs of light sources and sensors mounted on opposing extensions of each gripper. The light sources and detectors on each jaw are used to produce and detect the interruption of a pair of parallel light beams and/or a pair of crossed light beams by the object to be grasped. The gripper is rotated, translated, and/or closed in accordance with the detected status of the light beams in a simple table-driven manner by which the gripper is positioned to grasp the object with a stable grasping configuration. The gripper of the present invention can grasp an object of an unknown shape without disturbing or touching the object before grasping it.