提出了基于瞬时频率估计(Instantaneous frequency estimation,IFE)实现旋转机械阶比跟踪的新方法,其优点是简化了阶比分析对硬件的要求,用软件的方法实现了阶比跟踪,仿真与实际测试试验验证了本方法的正确性。本方法实现了旋转机械非...提出了基于瞬时频率估计(Instantaneous frequency estimation,IFE)实现旋转机械阶比跟踪的新方法,其优点是简化了阶比分析对硬件的要求,用软件的方法实现了阶比跟踪,仿真与实际测试试验验证了本方法的正确性。本方法实现了旋转机械非平稳振动信号中参考轴瞬时转速的跟踪、估计算法,为阶比分析的实际应用提供了一种新方法,是对原有阶比跟踪技术的有力补充,特别适合于虚拟仪器发展的要求。展开更多
Laser tracking system (LTS) is an advanced device for large size 3D coordinates measuring with the advantages of broad range, high speed and high accuracy. However, its measuring accuracy is highly dominated by the ...Laser tracking system (LTS) is an advanced device for large size 3D coordinates measuring with the advantages of broad range, high speed and high accuracy. However, its measuring accuracy is highly dominated by the geometric errors of the tracking mirror mechanism. Proper calibration of LTS is essential prior to the use of it for metrology. A kinematics model that describes not only the motion but also the geometric variations of LTS is developed. Through error analysis of the proposed model, it is claimed that gimbals axis misalignments and tracking mirror center off-set are the key contributors to measuring errors of LTS. A self-calibration method is presented of calibrating LTS with planar constraints. Various calibration strategies utilizing single-plane and multiple-plane constraints are proposed for different situations. For each calibration strategy, issues about the error parameter estimation of LTS are exploded to find out in which conditions these parameters can be uniquely estimated. Moreover, these conditions reveal the applicability of the planar constraints to LTS self-calibration. Intensive studies have been made to check validity of the theoretical results. The results show that the measuring accuracy of LTS has increased by 5 times since this technique for calibration is used.展开更多
文摘提出了基于瞬时频率估计(Instantaneous frequency estimation,IFE)实现旋转机械阶比跟踪的新方法,其优点是简化了阶比分析对硬件的要求,用软件的方法实现了阶比跟踪,仿真与实际测试试验验证了本方法的正确性。本方法实现了旋转机械非平稳振动信号中参考轴瞬时转速的跟踪、估计算法,为阶比分析的实际应用提供了一种新方法,是对原有阶比跟踪技术的有力补充,特别适合于虚拟仪器发展的要求。
基金National Natural Science Foundation of China (No. 50475038).
文摘Laser tracking system (LTS) is an advanced device for large size 3D coordinates measuring with the advantages of broad range, high speed and high accuracy. However, its measuring accuracy is highly dominated by the geometric errors of the tracking mirror mechanism. Proper calibration of LTS is essential prior to the use of it for metrology. A kinematics model that describes not only the motion but also the geometric variations of LTS is developed. Through error analysis of the proposed model, it is claimed that gimbals axis misalignments and tracking mirror center off-set are the key contributors to measuring errors of LTS. A self-calibration method is presented of calibrating LTS with planar constraints. Various calibration strategies utilizing single-plane and multiple-plane constraints are proposed for different situations. For each calibration strategy, issues about the error parameter estimation of LTS are exploded to find out in which conditions these parameters can be uniquely estimated. Moreover, these conditions reveal the applicability of the planar constraints to LTS self-calibration. Intensive studies have been made to check validity of the theoretical results. The results show that the measuring accuracy of LTS has increased by 5 times since this technique for calibration is used.