光跟踪控制器应用技术探析

光伏双轴跟踪系统的核心是算法,算法依托光跟踪控制器而存在,因此光跟踪控制器的重要性不言而喻。当阳光照射到感光传感器的时候,感光传感器会将采集的光照强度通过工业总线接口动态传输到控制器。根据不同季节的天气情况构建太阳光运动轨迹模型,在基于太阳光运动轨迹模型前提下,感光传感器传递过来的数据通过物理跟踪驱动算法处理后会产生相应的反馈驱动标志位,控制器会根据反馈驱动标志位直接驱动电机使光伏板垂直于阳光,完成一次调整周期。如此不断调整,时刻沿着太阳的运行轨迹追随太阳,构成一个闭路反馈系统,实现阳光的自动跟踪,让光伏发电效率持续最大化。

Comparison of Present SST Gravity Field Models

Taking the main land of Europe as the region to be studied, the potential of the new satellite gravity technique: satellite-to-satellite tracking (SST) and improving the accuracy of regional gravity field model with the SST models are investigated. The drawbacks of these models are discussed. With GPM98C as the reference, the gravity anomaly residuals of several other models, the latest SST global gravity field models (EIGEN series and GGM series), were computed and compared. The results of the comparison show that in the selected region, some systematic errors with periodical properties exist in the EIGEN and GGM’s S series models in the high degree and order. Some information that was not shown in the classic gravity models is detected in the low and middle degree and order of EIGEN and GGM’s S series models. At last, the effective maximum degrees and orders of SST models are suggested.

Optimization of superelevation runoff model for cycling tracks

To improve the possible superelevation runoff models for the cycling track design,at first,two existing representative superelevation runoff models used in China were investigated and fitted. Then,an optimization methodology was proposed,which was focused on the track geometry itself,without the consideration of the physical characteristic of the cyclist,assuming that less vertical curvature values correspond to less riding time. The riding performance formulae were obtained with the variables of riding time,riding velocity and vertical curvature of cycling track. Finally,with the refined adjustment on the vertical curvatures with the help of cycling track design software and considering the effect of horizontal alignments,the optimized models were finalized. It is clearly seen that these optimized models take the form of quartic parabola and are verified to achieve 0.005-0.021 s improvement in the event of 200 m time trial.

Modeling and simulation of quadrotor UAV based on Simscape

In order to speed up and simplify the design of the quadrotor unmanned aerial vehicle(UAV)and carry out experimental simulation and verification of relevant control algorithms,this paper analyzed the system dynamics model of the mechanical structure and flight principle of the quadrotor aircraft,and used the Newton-Euler method to derive the non-linear dynamic equations.Aiming at improving the modeling accuracy and system integrity of the quadrotor,the physical system modeling was combined with the CAD software and the Matlab/Simscape toolbox.The three-dimensional quadrotor solid model built by CAD software was imported into the Simscape simulation platform to construct the body and power system model of the quadrotor.Based on this,the control algorithm designed by Simulink was added to the simulation platform to facilitate the experiment verification and parameter tuning.The simulation results show that the designed aircraft can achieve hover and tracking well and meet the control performance requirements of the system.

黄石广播电视台高清虚拟演播室系统技术及应用解析

本文分析了黄石广播电视台建设的高清虚拟演播室系统中的关键技术,包括虚拟演播室系统的工作原理、色键器、蓝箱制作、物理跟踪、实时渲染平台、灯光布局、模型设计等,并分享了使用体会和心得。