This paper discusses how joint clearance influences robot end effectorpositioning accuracy and a robot accuracy analysis approach based on a virtual prototype isproposed. First, a 5-DOF(Degree of freedom) neurosurgery...This paper discusses how joint clearance influences robot end effectorpositioning accuracy and a robot accuracy analysis approach based on a virtual prototype isproposed. First, a 5-DOF(Degree of freedom) neurosurgery robot was introduced. Then we built itsvirtual prototype, made movement planning and measured the manipulator tip accuracy, through whichthis robot accuracy portrait was obtained. Finally, in order to validate the robot accuracyanalysis approach which is based on a virtual prototype, the result was compared with that from amodel built by robot forward kinematics and robot differential kinematics. The robot accuracyanalysis approach presented in this paper gives a new way to enhance robot design quality , and helpto optimize the control and programming of the robot.展开更多
The present study aims at developing high speed steel (HSS) as roll materialsto replace traditional roll materials such as the alloy cast iron and powder metallurgical (PM)hard alloy, because low-cost alloy cast iron ...The present study aims at developing high speed steel (HSS) as roll materialsto replace traditional roll materials such as the alloy cast iron and powder metallurgical (PM)hard alloy, because low-cost alloy cast iron rolls have poor wear resistance and the cost ofhigh-quality PM hard alloy rolls is too high to be accepted by some users. By means of a centrifugalcasting method, HSS rolls with excellent wear resistance have been developed. Its hardness is 65-67 HRC, and its variation is smaller than 2HRC; its impact toughness excels 15J/cm^2. Usingpre-finishing stands of a high-speed hot wire-rod rolling mill, the wear rate of HSS rolls per onethousand ton of steel is 0. 25mm. However, the manufacturing burden of HSS rolls is obviously lowerthan that of PM hard alloy rolls; it is only 30% of that of PM hard alloy rolls.展开更多
文摘This paper discusses how joint clearance influences robot end effectorpositioning accuracy and a robot accuracy analysis approach based on a virtual prototype isproposed. First, a 5-DOF(Degree of freedom) neurosurgery robot was introduced. Then we built itsvirtual prototype, made movement planning and measured the manipulator tip accuracy, through whichthis robot accuracy portrait was obtained. Finally, in order to validate the robot accuracyanalysis approach which is based on a virtual prototype, the result was compared with that from amodel built by robot forward kinematics and robot differential kinematics. The robot accuracyanalysis approach presented in this paper gives a new way to enhance robot design quality , and helpto optimize the control and programming of the robot.
文摘The present study aims at developing high speed steel (HSS) as roll materialsto replace traditional roll materials such as the alloy cast iron and powder metallurgical (PM)hard alloy, because low-cost alloy cast iron rolls have poor wear resistance and the cost ofhigh-quality PM hard alloy rolls is too high to be accepted by some users. By means of a centrifugalcasting method, HSS rolls with excellent wear resistance have been developed. Its hardness is 65-67 HRC, and its variation is smaller than 2HRC; its impact toughness excels 15J/cm^2. Usingpre-finishing stands of a high-speed hot wire-rod rolling mill, the wear rate of HSS rolls per onethousand ton of steel is 0. 25mm. However, the manufacturing burden of HSS rolls is obviously lowerthan that of PM hard alloy rolls; it is only 30% of that of PM hard alloy rolls.
