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Comparison of simulated backgrounds with in-orbit observations for HE, ME, and LE onboard Insight-HXMT 期刊论文 OAI收割
Astrophysics and Space Science, 2020, 卷号: 365, 页码: 158
作者: HXMT

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Insight-HXMT Geant4 simulation Background observation Astrophysics - Instrumentation and Methods for Astrophysics Abstract: Insight-HXMT, the first X-ray astronomical satellite in China, aims to reveal new sources in the Galaxy and to study fundamental physics of X-ray binaries from 1 to 250 keV. It has three collimated telescopes, the High Energy X-ray telescope (HE), the Medium Energy X-ray telescope (ME), and the Low Energy X-ray telescope (LE). Before the launch, in-orbit backgrounds of these three telescopes had been estimated through Geant4 simulation, in order to investigate the instrument performance and the achievement of scientific goals. In this work, these simulated backgrounds are compared with in-orbit observations. Good agreements are shown for all three telescopes. For HE, (1) the deviation of the simulated background rate after two years of operation in space is 5 % from the observation (2) the total background spectrum and the relative abundance of the 67 keV line show long-term increases both in simulations and observations. For ME, (1) the deviation of simulated background rate is within 15 % from the observation, and (2) there are no obvious long-term increase features in the background spectra of simulations and observations. For LE, the background level given by simulations is also consistent with observations. The consistencies of these comparisons validate that the Insight-HXMT mass model, i.e., space environment components and models adopted, physics processes selected, and detector constructions built, is reasonable. However, the line features at 7.5 and 8.0 keV, which are obvious in the observed spectra of LE, are not evident in simulations. This might result from uncertainties in the LE constructions.

Reentry guidance based on parametric optimization (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Mechatronics and Control Engineering, ICMCE 2012, November 29, 2012 - November 30, 2012, Guangzhou, China
作者: Li D.

收藏 | 浏览/下载：163/0 | 提交时间：2013/03/25

This paper presents a parametric optimization approach to solve reentry guidance. Due to the various constraints imposed on the trajectory original guidance problem can be converted into an optimal control problem with a merit function to be minimized. Direct implementation of method of variation and is too complex to get a reasonable result while a numerical parametric optimization approach is feasible and efficient if we choose appropriate control variables as the optimization parameters and effective optimization algorithm. A simulation of the approach is performed to show its validity on reentry guidance problem: as the value of merit function converges to acceptable threshold all constraints are hold. (2013) Trans Tech Publications Switzerland.

Longitudinal control law design and simulation of fixed-wing UAV (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Measurement, Instrumentation and Automation, ICMIA 2012, September 15, 2012 - September 16, 2012, Guangzhou, China
作者: Duan Z.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

Taken some fixed-wing UAV as the study object the aircraft movement was broken down into the longitudinal movement and lateral movement according to the linearized small perturbation principle the longitudinal control law design method was discussed using root locus which belonged to classical control theory. The six degrees of freedom nonlinear model simulation result shows that: the control parameters designed are reasonable the simulation profile is fully consistent with the setting profile the control effect of pitch angle loop and altitude loop meets with the indices requirements the method is mature and reliable easy to realize in engineering. (2013) Trans Tech Publications Switzerland.

Simulation test system of CCD signal processor based on FPGA (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan
作者: Zhang D.; Liu D.-B.; Zhang D.

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Simulation test system of CCD signal processor based on FPGA is proposed. Field-programmable gate array (FPGA) is applied as control processing core and used in the aerospace upgrade screening of industrial grade signal processor. The system functional composition and working principle were introduced in detail. Actually evaluation and testing system was completed with integrating the forty signal processor in a single board. The system has been successfully applied in the dynamic build-in screening test of industrial grade signal processor XRD98L63 the system work stably and reliability. Test result is zero on the nonconforming product rate satisfying the qualification that single batch screening nonconforming rate is less than 5% build-in screening of industrial grade components for the space load applications is implemented. (2013) Trans Tech Publications Switzerland.

Data normalization of single camera visual measurement network system (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Information Technology and Management Innovation, ICITMI 2012, November 10, 2012 - November 11, 2012, Guangzhou, China
作者: Zhang Y.-C.; Zhou J.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

With the development of visual measurement system Normalize the measured coordinates into the same world coordinate system Apply in the three coordinate measuring machine(CMM) to have the simulation experiment So the data normalization has the advantage of more high precision. (2013) Trans Tech Publications the visual measurement system of single camera which applied in the imaging theory of optical feature points then get the global data the result indicates that the maximum absolute tolerance between the normalization coordinates via the center of point set and the ones measured by CMM directly is 0.058mm Switzerland. it has been widespread used in the modern production. Due to the limit of the environment in scene and achieve the overall measurement the visual measurement system of single camera could not measure the shield between the measured objects each other. Focus on this problem But the one between the coordinate repeatedly measured at the position of one network control point is 0.066mm present a kind of the the knowledge of measurement network based on the visual measurement of single camera set up the measurement network system via the multi-control points. Measure the optical feature points in every network control point via the visual measurement system of single camera

Precision analysis of simulation systems with hardware-in-loop caused by performance of three-Axis virtual flight motion simulator (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Manufacturing Science and Technology, ICMST 2011, September 16, 2011 - September 18, 2011, Singapore, Singapore
Wang T.; Zhu M.-C.; Yin S.-L.; Jia H.-G.

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Simulation systems with hardware-in-loop are composed by three-Axis virtual flight motion simulator simulation computer load torque simulator and visual simulation systems. Three-Axis Virtual Flight Motion Simulator are used to simulate the attitude of missile in simulation system with hardware-in-loop so its performance influenced the result of simulation directly. This paper mainly analyzed the factors which influenced the performance of a three-Axis virtual flight motion simulator which we are used now in the lab then analyzed the entire simulation system's error caused by these factors through numerical simulation method. By analysis we can see that bandwidth is the main factor influenced the precision of simulation systems with hardware-in-loop mechanical device installation error and measurement error may also cause some errors of the systems at the same time.

The design of space scanning mirror control system based on optimal tracking controller (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Electrical Insulating Materials and Electrical Engineering, EIMEE 2012, May 25, 2012 - May 27, 2012, Shenyang, Liaoning, China
作者: Zhang P.

收藏 | 浏览/下载：19/0 | 提交时间：2013/03/25

Control system of space scanning mirror has high requirement of scanning accuracy. The use of optimal tracking controller simulation experiment of the control system based on optimal tracking controller is carried out. The simulation result instead of traditional PID controller the control system based on optimal tracking controller is designed in comparison with the system based on a PID controller can effectively improve the scanning accuracy of space scanning mirror control system. State space model of the control system is established shows that the scanning mirror control system using optimal tracking controller instead of PID controller has higher scanning accuracy and faster response. (2012) Trans Tech Publications Switzerland.

The design of computer-generated holograms for testing unsymmetrical optical surfaces (EI CONFERENCE) 会议论文 OAI收割
2012 International Symposium on Photonics and Optoelectronics, SOPO 2012, May 21, 2012 - May 23, 2012, Shanghai, China
作者: Zhang X.; Zhang Y.; Zhang X.; Zhang X.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

It is a technical difficulty to test the unsymmtrical optical surfaces in non-contact methods. But we can do it using computer-generated holograms (CGH). The principle and design of the CGH have been discussed in the paper. Take the cubic suface as an example The order separation of the CGH is analyzed theoretically and the simulation result of the order separation is given in the paper. We develop the binary process of the continuous CGH phase function and get the sample of the amplitude CGH. A CGH for testing a cubic phase plate with duty cycle 0.5 is fabricated by using e-beam lithographic techniques. In this situation the contrast of the interference fringe pattern can achieve a level of 99.4% by calculation. 2012 IEEE.

Numerical simulation on efficient spinning technology based on multi-point adjusting principle (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Manufacturing Science and Engineering, ICMSE 2011, April 9, 2011 - April 11, 2011, Guilin, China
Gong X. P.

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In order to realize high efficiency and flexible manufacturing for rotary surfaces equivalent stress in sheet metal's center region and bendable rollers active region exceeds yield stress efficient spinning technology (EST) is researched. It is the combination of multi-point forming and traditional spinning. Principle of EST is described and plastic deformation is generated traditional spinning method is compared with it experimental result accords with simulation result. Feasibility of EST is validated by simulation and experimental results. (2011) Trans Tech Publications. and characteristics of it are analyzed. Finite element analysis (FEA) model of disc-shape part is established EST process is analyzed equivalent stress and plastic strain distributions are analyzed. EST equipment is developed and the experiments are made. Results indicate: EST process consists of four stages

Research on model reference sliding mode control in roll stabilization of aerocraft (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
Chu H.-R.

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Aimed at aerospace roll stabilization control arithmetic based on model reference sliding mode variable structure theory and chattering reduction arithmetic are formulated. Correctness and validity of arithmetic are analyzed. With flight dynamics the roll-loop mathematic model and reference model are established. Sliding hyperplane is deduced based on model reference sliding mode variable structure theory. Combing with reaching law control law is derived and stability of roll-loop is analyzed. Chattering of aileron instructions is alleviate by using boundary layer approach. Digital flying simulation result shows that variable structure control arithmetic realized roll stabilization control the roll angle is less than 5.3 under powered flight and that of unpowered flight is less than 0.5 respectively. The command fin angle is less than 1.5. High frequency chattering of fin command nearby the minimum velocity was trailed off by chattering reduction arithmetic. The sliding mode control arithmetic show good performance when aerodynamic coefficients varies 20%. The control arithmetic is easy to be implemented for its simplicity. 2011 IEEE.