Development of Mine Detection Robot System
The Mine Detection Robot supports the mine removal work in countries where mines are buried, such as Afghanistan. The development started from September, 2003. Considering running on rough terrains, the robot has four crawlers, and hydraulic motors in front and rear were serially connected by piping so that they could rotate synchronously. Two work arms were mounted on the robot, one was a horizontal multi-joint SCARA type with motorized 2-link arm, while the other was a vertical multi-joint manipulator with 6 degrees of freedom. Also, domestic evaluation tests were carried out from February to March, 2005, followed by overseas validation tests in Croatia from February to March, 2006. These tests were conducted with a mine detecting senor mounted on the Robot, and the detection performance was evaluated by its mine detection rate.
Robot Navigation Based on Multi-sensor Data Fusion
This paper mainly focuses on a multi-sensor system for combining data from infrared and ultrasonic sensors in the navigation of coal mine rescue robots, meanwhile a navigation method is presented. A multiple infrared and ultrasonic sensor system has been developed for complete coverage navigation of a robot. By fusing the aspects of different sensors with different beam-widths, more efficient colLision avoidance behavior in robot control can be obtained. A navigation method using TOF, ampLitude characteristic and trigonometry are appLied to solve such problems as obstacle detection, obstacle avoidance and path-planning. Simulation results demonstrate that the robot is capable of bypassing obstacles agilely and reach the destination smoothly and reLiably, at the same time the precise position and orientation information of the robot are updated using the previous robot locaLization studies.
The microscale obstacle-resolving meteorological model MITRAS v2.0: model theory
Abstract. This paper describes the developing theory and underlying
processes of the microscale obstacle-resolving model MITRAS version 2. MITRAS
calculates wind, temperature, humidity, and precipitation fields, as well as
transport within the obstacle layer using Reynolds averaging. It explicitly
resolves obstacles, including buildings and overhanging obstacles, to
consider their aerodynamic and thermodynamic effects. Buildings are
represented by impermeable grid cells at the building positions so that the
wind speed vanishes in these grid cells. Wall functions are used to calculate
appropriate turbulent fluxes. Most exchange processes at the obstacle
surfaces are considered in MITRAS, including turbulent and radiative
processes, in order to obtain an accurate surface temperature. MITRAS is also
able to simulate the effect of wind turbines. They are parameterized using
the actuator-disk concept to account for the reduction in wind speed. The
turbulence generation in the wake of a wind turbine is parameterized by
adding an additional part to the turbulence mechanical production term in the
turbulent kinetic energy equation. Effects of trees are considered
explicitly, including the wind speed reduction, turbulence production, and
dissipation due to drag forces from plant foliage elements, as well as the
radiation absorption and shading. The paper provides not only
documentation of the model dynamics and numerical framework but also a solid
foundation for future microscale model extensions.
