摘要:
This paper describes the development of the second-generation Spherical Underwater Robot (SUR-II). The new SUR-II has an improved propulsion system structure, resulting in better performance compared with the original design. This paper focuses on the characteristics of the water-jet thruster and the spherical hull of the SUR-II. To analyse its hydrodynamic characteristics, the main hydrodynamic parameters of the SUR-II were estimated based on two reasonable assumptions and a reasonable dynamic equation was proposed to describe the relationship between force and velocity. Drag coefficients were calculated separately for vertical and horizontal motions due to the fin on the robot's equator and the holes in the robot's hull. The holes had a particularly adverse effect on the horizontal drag coefficient. A hydrodynamic analysis using computational fluid dynamics was then carried out to verify the estimated parameters. The velocity vectors, pressure contours and drag coefficient for each state of motion were obtained. Finally, the propulsive force was determined experimentally to verify the theoretical calculations and simulation results.
摘要:
加州大学伯克利分校的Engine—ering7课程(Introduction to ProgrammIng for Eng—lneers,工程师编程介绍),简称为E7,每个学期都会招收400多名新生。该课程主要为学生讲授一些在整个大学期间,以及工作中,都能运用的编程技能。E7通过MATLAB0进行授课已经有超过15年的历史。除了帮助学生们快速学习计算机编程的基础以外,对于学习如何运用数学模型和计算方法,MATLAB也是一个非常理想的环境。
摘要:
Patterns of qualitative concepts are extracted from robot sensors in order to describe the shapes, colours, spatial orientations and topology situations of natural landmarks in the robot environment and also the distance to them. Those qualitative patterns are obtained at a low level sensor data processing and without using training on datasets or learning techniques. A qualitative distance integration approach is parametrized and applied to detect glass windows and mirrors. Corners and columns are detected by the laser sensor and described qualitatively as relevant landmarks. Images taken by the robot camera are described qualitatively for completing the description of the objects located in the robot environment. Experimentation carried out shows that the integration of the information provided enhances the robot perception. (C) 2012 Elsevier B.V. All rights reserved.