为了提高双直线电动机驱动的同步直接进给轴的运动精度,对该类直接进给轴的全行程热误差在线补偿方法进行了研究。分析了双直接进给轴全行程热误差的影响因素,提出一种基于核偏最小二乘法(Kernel partial least squares,KPLS)和模糊逻...为了提高双直线电动机驱动的同步直接进给轴的运动精度,对该类直接进给轴的全行程热误差在线补偿方法进行了研究。分析了双直接进给轴全行程热误差的影响因素,提出一种基于核偏最小二乘法(Kernel partial least squares,KPLS)和模糊逻辑相结合的双直接进给轴全行程热误差的在线补偿方法。应用激光干涉仪测量其热变形量,使用热电偶和红外测温仪测量进给机构关键点的温度,以时间匹配温度和变形量数据建立统计样本,在均匀离散点位置建立热误差KPLS识别模型,通过在线计算得到离散点热误差补偿量,再根据任意位置与离散点的模糊关联程度,综合计算全行程任意位置处热误差补偿量。以此理论为基础,建立补偿决策函数和补偿系统,依据补偿决策函数智能推断补偿值,通过向数控系统发送补偿码实现在线补偿。在自构建的龙门双直线电动机驱动的直接进给轴平台上,进行全行程热误差在线补偿试验研究,结果表明:混合KPLS与模糊逻辑可以有效的对双直接进给轴全行程热误差在线补偿,经过随机测试验证,补偿后的进给精度提高了50%。展开更多
Modern VLSI circuits provide adequate on-chip resources. So that online testing and retry integrated into a chip are absolutely necessary for system-on-a-chip technology. This paper firstly proposes a general online t...Modern VLSI circuits provide adequate on-chip resources. So that online testing and retry integrated into a chip are absolutely necessary for system-on-a-chip technology. This paper firstly proposes a general online testing plus retrying structure. Obviously, although retry can mask transient or intermittent faults, it is useless for handling permanent faults generally. To solve this problem, this paper presents a novel dual modular redundancy (DMR) structure using complementary logic--alternating-complementary logic (CL-ACL) switching mode. During error-free operation, the CL-ACL structure operates by complementary logic mode. After an error is detected, it retries by alternating logic mode. If all errors belong to single or multiple temporary 0/1-error or stuck-at-error produced by one module, then these errors can be corrected effectively. The results obtained from the simulation validate the correctness of the CL-ACL structure. Analytic results show that the delay of the CL-ACL structure is dramatically less than that of a DMR structure using alternating-complementary logic mode.展开更多
基金supported by the National Nature Science Foundation of China(61304223)the Aeronautical Science Foundation of China(2016ZA52009)the Research Fund for the Doctoral Program of Higher Education of China(20123218120015)
文摘为了提高双直线电动机驱动的同步直接进给轴的运动精度,对该类直接进给轴的全行程热误差在线补偿方法进行了研究。分析了双直接进给轴全行程热误差的影响因素,提出一种基于核偏最小二乘法(Kernel partial least squares,KPLS)和模糊逻辑相结合的双直接进给轴全行程热误差的在线补偿方法。应用激光干涉仪测量其热变形量,使用热电偶和红外测温仪测量进给机构关键点的温度,以时间匹配温度和变形量数据建立统计样本,在均匀离散点位置建立热误差KPLS识别模型,通过在线计算得到离散点热误差补偿量,再根据任意位置与离散点的模糊关联程度,综合计算全行程任意位置处热误差补偿量。以此理论为基础,建立补偿决策函数和补偿系统,依据补偿决策函数智能推断补偿值,通过向数控系统发送补偿码实现在线补偿。在自构建的龙门双直线电动机驱动的直接进给轴平台上,进行全行程热误差在线补偿试验研究,结果表明:混合KPLS与模糊逻辑可以有效的对双直接进给轴全行程热误差在线补偿,经过随机测试验证,补偿后的进给精度提高了50%。
文摘Modern VLSI circuits provide adequate on-chip resources. So that online testing and retry integrated into a chip are absolutely necessary for system-on-a-chip technology. This paper firstly proposes a general online testing plus retrying structure. Obviously, although retry can mask transient or intermittent faults, it is useless for handling permanent faults generally. To solve this problem, this paper presents a novel dual modular redundancy (DMR) structure using complementary logic--alternating-complementary logic (CL-ACL) switching mode. During error-free operation, the CL-ACL structure operates by complementary logic mode. After an error is detected, it retries by alternating logic mode. If all errors belong to single or multiple temporary 0/1-error or stuck-at-error produced by one module, then these errors can be corrected effectively. The results obtained from the simulation validate the correctness of the CL-ACL structure. Analytic results show that the delay of the CL-ACL structure is dramatically less than that of a DMR structure using alternating-complementary logic mode.