为提高注水管道中数据提取效率,缩短现场作业时间。面向基于RFID(Radio Frequency Identification,射频识别)的注水控制系统,设计了一套近场数据传输系统,包括无线接口、硬件实现以及通讯协议。利用该系统可以省去管道拆卸和密封等步骤,完成管道内数据的提取,大幅度缩短单口井作业时间,降低了作业成本。系统在江汉油田得到应用,可以在管道指令传输和数据传输等场合推广使用。
This paper presents an approach to algebraic detection of relative form closure for a multi-fingered grasp G and gives an attention to the classification of relative form closures.Whether or not a grasp G is of relative form closure has been verified by the geometric criterion 0?rintC[G](Xiong Y L,Xiong X R.Algebraic structure and geometric interpretation of rigid complex fixture system.IEEE Trans Autom Sci Eng,2007,4:252–264;Xiong Y L.Theory of point contact restraint and qualitative analysis of robot grasping.Sci China Ser A-Math,1994,37:629–640).Our aim is at transferring the geometric criterion into an algebraic formulation by a theorem that a grasp G is relative form closure,if,and only if the origin 0 can be represented as a positive convex combination of G.So we develop a constructive procedure called ri-simplex algorithm to find a positive convex combination of G when it has relative form closure.Form closure is considered as a special case of relative form closure,when the grasp G can affinely span the whole space,while partly relative form closure is referred to as form closed relative to a subset G1 of G.
