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A new simple and effective inertial parameter identification method based on sinusoidal vibrations of a six-degree-of-freedom parallel manipulator is proposed. Compared with previously known identification algorithms, the advantages of the new approach are there is no need to design the excitation trajectory to consider the condition number of the observation matrix and the inertial matrix can be accurately defined regardless of the effect of viscous friction. In addition, the use of a sinusoidal exciting trajectory allows calculation of the velocities and accelerations from the measured position response. Simulations show that the new approach has acceptable tolerance of dry friction when using a simple coupling parameter modified formula. The experimental application to the hydraulically driven Stewart platform demonstrates the capability and efficiency of the proposed identification method. 相似文献
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介绍网带炉在静态不充气、充气及动态充气等状态下,温场的测量方法;并就冷态空载、负载运行时间及加热空载、负载运行时间的测量进行了讨论和分析。 相似文献
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Ruhai Wang Stephen Horan Bingxin Tian Sreelakshmi Bonasu 《IEEE transactions on aerospace and electronic systems》2006,42(4):1311-1322
The acknowledgement (ACK) strategy of transmission control protocol (TCP) has been modified to delay the ACKs for a configurable period of time that is related to the round-trip time (RTT) to improve its performance in asymmetric links such as space communications. A general relationship between the asymmetric channel ratio and the optimal ACK frequency to achieve maximum throughput is not available. This paper studies the optimal ACK frequency with respect to the channel RTT to achieve the maximum throughput over various asymmetric, geo-stationary earth orbit (GEO)-satellite links using a test-bed. It is found that when the asymmetric channel ratio is as high as about 100/1, the optimal ACK frequency must be increased with an increase in asymmetric ratio to complement the impact of the reduction of ACK channel rate. As a rule of thumb, every two-fold increase in asymmetric ratio requires the optimal ACK frequency to be increased by one ACK per RTT. A regression model was built to reflect the relationship between the optimal ACK frequency and the asymmetric channel ratio and has been validated 相似文献