We investigate the homogenization limit of a free boundary problem with space-dependent free boundary velocities. The problem under consideration has a well-known obstacle problem transformation, formally obtained by integrating with respect to the time variable. By making rigorous the link between these two problems, we are able to derive an explicit formula for the homogenized free boundary v...

Remote labs are increasingly being used as an effective tool for letting students practicing with real experiments, with limited effort and cost. A multi-robot setup, based on the LEGOMindstorms technology and the Matlab environment, allowing students to experiment with real robots through the Internet, has been developed. In this paper, a novel feature of this setup is presented. The concept o...

In this paper, we present a novel methodology to perform collective transport in the presence of obstacles. Three robots are physically connected in a semicircle around an object to be transported from a start to a goal location. The task poses two main challenges. First, the presence of both a goal and obstacles requires appropriate negotiation of the direction among the members of the group. ...

This paper presents WOAH, a method for real-time mobile robot path following and obstacle avoidance. WOAH provides reactive speed and turn instructions based on obstacle information sensed by a laser range finder. Unlike many previous techniques, this method allows a robot to move quickly past obstacles that are not directly in its path, avoiding slowdowns in path following encountered by previ...

The focus of this paper is a numerical simulation study the flow dynamics in periodic porous medium to analyse physics symmetry-breaking phenomenon, which causes deviation direction macroscale from that applied pressure gradient. phenomenon prominent range porosity 0.43 0.72 for circular solid obstacles. It result instabilities formed when surface forces on obstacles compete with inertial force...

Predicting solid particle transport in the lowest parts of atmosphere is a major issue for man-made obstacles semi-arid regions. Here, we investigate effects on saltation, square ground with different spacings. The aerodynamic field determined by large eddy simulations coupled an immersed boundary method obstacles. Solid particles are tracked Lagrangian approach. Take-off and rebound models int...

In this paper a reactive and concurrent control framework for viewpoint control is developed. The viewpoint control task is decomposed into three control objectives namely; obstacle avoidance, visibility and precision. A moving object is tracked in two panoramic sensors using color, and a scalar uncertainty metric of the object position estimate is introduced. Individual control objectives are ...

Learning by observation allows a software agent to learn an expert’s behaviour, by examining the actions the expert performs in response to inputs, without the expert having to explicitly program the agent. Most learning by observation approaches only make use of the current inputs and actions of the expert and ignore any past inputs or actions. This limits the agents to only being able to lear...

Estimation of local second-degree variation should be a natural first step in computerized image analysis, just as it seems to be in human vision. A prevailing obstacle is that the second derivatives entangle the three features signal strength (i.e. magnitude or energy), orientation and shape. To disentangle these features we propose a technique where the orientation of an arbitrary pattern f i...

We consider an obstacle-type problem ∆u = f(x)χΩ in D u = |∇u| = 0 on D \ Ω, where D is a given open set in Rn and Ω is an unknown open subset of D. The problem originates in potential theory, in connection with harmonic continuation of potentials. The qualitative difference between this problem and the classical obstacle problem is that the solutions here are allowed to change sign. Using geom...