We approach dynamic collision avoidance problem from the perspective of designing collision avoidance systems for unmanned aerial vehicles. Before unmanned aircraft can fly safely in civil airspace, robust airborne collision avoidance systems must be developed. Instead of hand-crafting a collision avoidance algorithm for every combination of sensor and aircraft configurations, we investigate au...

Collision detection is a fundamental issue for the safety of a robotic cell. While several common methods require specific sensors or the knowledge of the robot dynamic model, the proposed solution is constituted by a virtual collision sensor for industrial manipulators, which requires as inputs only the motor currents measured by the standard sensors that equip a manipulator and the estimated ...

We consider the first collision time for a set of independent one-dimensional zero-drift Wiener processes. For the 3-process problem, the first collision time corresponds to the first exit time of Brownian motion in a cone in W’, and we can apply the results of Spitzer (1958) and Dante DeBlassie (1987) to obtain its distribution. In the case where the processes have equal infinitesimal variance...

This article reports a model study aimed at the detailed description of the mechanism of formation of molecular hydrogen onto dust grain surfaces in the interstellar medium. Using classical trajectories (CT) and quasi-classical trajectories (QCT) calculations, the H2 recombination from the Eley-Rideal process has been studied. This reactive process, involving the collision between one gas phase...