A new castor wheel mechanism for omni-directional mobile platform is presented. A motion of translation is transformed into a rotation to steer the wheel with the help of a helical path fits into a translation joint a...A new castor wheel mechanism for omni-directional mobile platform is presented. A motion of translation is transformed into a rotation to steer the wheel with the help of a helical path fits into a translation joint and three rollers whose axes are connected to the driving shaft of the wheel. When the path moves in translation it acts on the rollers for steering. The path-roller friction transmission, the wheel kinematics and the maneuverability have been analyzed.展开更多
The aim of this investigation was to improve power performance of Savonius hydraulic turbine utilizing small stream for electric generation.An attempt was made to increase the power coefficient of runner by the use of...The aim of this investigation was to improve power performance of Savonius hydraulic turbine utilizing small stream for electric generation.An attempt was made to increase the power coefficient of runner by the use of flat shield plate placed upstream of the runner.The difference of the power coefficient is discussed in relation to clearance between the runner and the bottom wall and the rotation direction of the runner.The flow field around the runner was also examined visually to clarify influences of setting conditions on the power performance.From this study it was found that the power coefficient is achieved for 0.47 by only using a flat shield plate,the increase is up to 80% over the runner without the plate.Moreover,it is the proper condition that clearance ratio is 0.73 in this study.展开更多
文摘A new castor wheel mechanism for omni-directional mobile platform is presented. A motion of translation is transformed into a rotation to steer the wheel with the help of a helical path fits into a translation joint and three rollers whose axes are connected to the driving shaft of the wheel. When the path moves in translation it acts on the rollers for steering. The path-roller friction transmission, the wheel kinematics and the maneuverability have been analyzed.
基金supported by KAKENHI No.2231004 and Ministry of Environment
文摘The aim of this investigation was to improve power performance of Savonius hydraulic turbine utilizing small stream for electric generation.An attempt was made to increase the power coefficient of runner by the use of flat shield plate placed upstream of the runner.The difference of the power coefficient is discussed in relation to clearance between the runner and the bottom wall and the rotation direction of the runner.The flow field around the runner was also examined visually to clarify influences of setting conditions on the power performance.From this study it was found that the power coefficient is achieved for 0.47 by only using a flat shield plate,the increase is up to 80% over the runner without the plate.Moreover,it is the proper condition that clearance ratio is 0.73 in this study.
