Motion planning for a robot and a movable object amidst polygonal obstacles. A new geometrical approach to planing manipulation tasks. the case of a circular robot and a movable circular object amidst polygonal obstacles. Figure 23: The problem of rotational pushing. (A) describes a square object aligned to the grid. The dots show all possible (discretized) conngurations that the robot can take...

We show that the typical wind-tree model, in the sense of Baire, is recurrent and has a dense set of periodic orbits. The recurrence result also holds for the Lorentz gas : the typical Lorentz gas, in the sense of Baire, is recurrent. These Lorentz gases need not be of finite horizon! In 1912 Paul and Tatiana Ehrenfest proposed the wind-tree model of diffusion in order to study the statistical ...

[Purpose] This study examined the relationship between the center of pressure (COP) displacement time during the stance subphases and dynamic balance ability when elderly cross obstacles 0, 10, and 40 cm in height. [Subjects] Fifteen older adults were enrolled in this study (≥65 years of age). [Methods] An F-Scan System was used to measure the COP displacement time when subjects crossed obstacl...

Inertial microfluidics manipulates and separates microparticles based on the finite inertia of fluid at high flow speed. In inertial microfluidics, modifying geometry by embedding periodic micro-obstacles into curvilinear channels is emerging as a promising strategy to improve focusing separation. This work systematically investigated influence developed high-resolution microfluidic device for ...

This special issue encompasses the experimental and theoretical investigations on transport phenomena of nanofluids in cavities. The contributions are classified as follows: (1) nanofluid flow square/rectangular cavities, (2) cavities with obstacles, (3) wavy enclosures, (4) trapezoidal/circular/annular (5) enclosures.

In unlabeled multi-robot motion planning several interchangeable robots operate in a common workspace. The goal is to move the robots to a set of target positions such that each position will be occupied by some robot. In this paper, we study this problem for the specific case of unit-square robots moving amidst polygonal obstacles and show that it is PSPACE-hard. We also consider three additio...

We take some parts of a theoretical mobility model in two-dimension grid proposed by Greenlaw and Kantabutra to be our model. The has eight necessary factors that we commonly use mobile wireless network: sources or signal providers, the directions source can move, users devices, given which define user's movement, source's velocity, coverage, obstacles. However, include only sources, obstacles ...