机器人腕部力传感器的标定

力反馈是机器人控制技术中一种重要的反馈。位于机器人手臂和夹持器之间的腕部力传感器是最重要的力传感器。对力传感器进行标定就是找出其标定矩阵。作者提出了求标定矩阵的方法,并指出Shimino和美国机器人技术公司——RTI的标定方法是错误的。专门设计的实验表明,用作者提出的方法所得的标定矩阵进行计算,测定载荷与实际施加的载荷是相接近的,而RTI公司的结果与施加载荷相差甚大。作者还提出了一种简化的6×6标定矩阵,用其计算的结果也与实际施加载荷接近。     

三向力传感器标定算法的实验研究

为研究三向力传感器标定算法的有效性,设计一种非对称结构的三向力传感器,并对该传感器采用单向加载的方式进行大样本标定实验,将实验数据代入标定算法,得到该三向力传感器的标定表达式.再对传感器多次进行空间任意方向力加载,记录加载力大小和方向角,将加载时的三个应变输出代入三向力传感器标定表达式,得到标定结果.通过将标定结果与实际加载值进行比较,得出三向力传感器的标定误差.实验结果表明:该三向力传感器标定算法具有一定的标定精度.     

多维力/力矩传感器动态标定中若干问题的研究

动态标定实验是把握传感器动态特性的基础,是进行系统辨识、补偿和解耦所必需的.文章讨论了六维腕力传感器阶跃和冲击2种动态标定实验的设备和实验过程,求得其动态性能指标,分析了2种标定中存在的问题,并提出了改进多维腕力传感器动态标定实验的建议.     

基于拉丝法的线结构光视觉测量系统标定

 利用线结构光视觉非接触测量技术的大量程、大视场、高精度、光纹信息提取简单等优点进行非接触测量大型机器及轨道等。分析了线结构光视觉测量传感器数学模型,利用构建的位于光平面上的标定特征点,提出了一种基于拉丝法的线结构光视觉测量标定方法,即先标定传感器相机的内外参数,再利用激光线与铁丝相交形成的点作为特征点标定光平面在相机坐标系下的方程。该方法降低了标定设备的成本,过程简单。标定结果表明：该方法标定满足测量要求。     

一种基于双平行平面的激光雷达和摄像机标定方法

针对单线激光雷达和摄像头的外参数估计问题,提出一种基于双平行平面的标定方法,标定过程分为单传感器相对车体位姿的标定和多传感器联合标定2个部分.利用激光雷达在双平行的平面标定板上的扫描信息,获取激光雷达相对于车体的俯仰角度和偏转角度;通过黑白棋盘格获取摄像头相对于车体的姿态外参数;最后综合前两步的结果和两种传感器在车体的精确安装位置,对激光雷达、摄像头和车体进行联合标定.本文提出的方法只要让标定物放置于车体正前方,采集一次数据就能满足整个标定过程,实现多个传感器的联合标定.实验结果表明,该方法的标定精度较高,简单实用.     

多维腕力传感器静态解耦的研究

传感器的静态耦合是制约多维力传感器测量精度的一个主要因素。文章总结了腕力传感器静态线性解耦的主要研究内容,提出静态非线性耦合问题,探索静态非线性标定方法,给出了一种非线性解耦方法,仿真结果充分证明其有效性。     

圆结构光传感器标定方法

研究用于管件内表面三维测量的圆结构光传感器标定方法. 圆结构光传感器由激光发生器、反射锥镜和CCD相机组成,激光器发射的光经锥镜反射后与被测表面相交,通过分析传感器的成像几何关系,提出了一种快速的、采用多个圆环的标定方法,通过标定确定光曲面的关键参数. 采用标定后的圆结构光传感器对已知直径的圆环进行测量,直径测量误差为±0.2mm. 该标定方法实现简单,满足现场标定的要求,同时能够保证一定的精度.     

一种新的高精度的线结构光传感器标定方法

提出了一种新的高精度的线结构光传感器标定方法。这种方法仅需一个简单标定靶和一个一维工作台,且不用另外的仪器来测量光平面上点的光标,即可实现对线结构光传感器参数的高精度、快速的标定。该方法可对可见光和不可见光的场合均适用。     

线性压力传感器的静态标定

以静态标定理论为基础，对原航空工业部线性压力传感器静态检测标准存在的问题进行了研究，并提出一种线性压力传感器全自动静态标定方法，该方法能减少过去对压力标准源精度的依赖及检定循环次数，提高标定工作效率，降低标设备的成本，弥补现行标准中的不足。     

移动式防盗报警器

一种新型的、由传感器和报警电路组成的报警器试制成功。其特点是传感器上、下两端为U型金属壳,中部为玻璃管,它们构成一个封闭体,该封闭体内设有一细弹簧,细弹簧上端固定在上U型金属壳的内表面上,细弹簧的下端焊有锡头,锡头正好位于下U型金属壳内。上、下U型金属壳分别通过导线接入报警电路。报警器的传感器结构示意图如图1;电原理图如图2所示。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.