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2008 Vol. 34, No. 05

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Analysis of aerodynamics characteristic of flexible wing caused by deflection
Zhang Hua, Ma Dongli, Ma Tielin
2008, 34(05): 487-490.
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A high-fidelity numerical simulation was presented for the flexible high-aspect ratio composite wing because of its high-speed nonlinear aeroelastic behavior. The fluid-structure interaction procedure used a loosely-coupled methodology. The compressible flow was modeled using the 3-D N-S equations on a deformable mesh, and the computational structural mechanics modeled in a steady analysis with geometrically-nonlinear effects. The transfer of distributed loads and displacements at the fluid-structure interface was based on detailed 3-D representations. Using this approach, a representative high-aspect-ratio composite forward-swept and backwards-swept wing were investigated for the steady flight conditions. Finally, the solution was implemented for the loosely-coupled fluid-structure interaction problem. Compared with the forward-swept wing, the lift coefficient of backwards-swept wing decreases obviously, the lift-drag ratio reduces markedly, which is obviously different from the rigid wing, so it must be considered during the design of a flexible wing.
Multidisciplinary design optimization of flight control law and control effectors for plane
Zhang Dengfeng, Gao Jinyuan
2008, 34(05): 491-494.
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Based on approximate models and genetic arithmetic, a scheme for the plane with multi-flaps was proposed to implement the multidisciplinary design optimization (MDO) of full-envelope flight control law and control effectors- geometry & their placement. The robust gain-schedule control method was applied to develop the full-envelope flight control system with the form of moment control in this scheme, and design of experiment (DOE) method as well as radial basis function nerve-network (RBF NN) response surface method was used to obtain approximate models for aerodynamics discipline and control discipline. Then the optimized design parameters were achieved with the genetic arithmetic based on approximate models, and the optimized flight control low & control effectors were finally obtained. On the computer the scheme was validated for a tailless plane with multi-flaps. The simulation result shows the feasibility of the scheme.
Studies on error of active optical pulse replicator
Yang Yi, Zheng Zheng, Li Zheng, Chen Yuxiao
2008, 34(05): 495-498.
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The replicating errors of active fiber loop replicator (AFLR) were discussed by using a dynamic model of noisy of semiconductor optical amplifier(SOA) and Monte-Carlo method. The replicating error changing due to the attenuation in fiber loop, the bias current of SOA, wavelength of assist light and peak power of replicated pulse were analyzed. The results show that low attenuation and middle bias current are preferred to achieve low replicating error. And the assist light should choose long wavelength. The methods to minimize replicating error were given by using numerical analysis. An experimental study about replicating performance of AFLR was presented at end. Experiment shows that AFLR can replicate pulse with low error.
Analysis of scattering from serrated edge plate on aircraft with MLFMA
Liu Zhanhe, Huang Peilin, Wu Zhe, Gao Xu
2008, 34(05): 499-502.
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Combined field integral equation (CFIE), multilevel fast multipole algorithm (MLFMA) and conjugate grads method(CGM) were employed, and a modified truncation number had been presented to gain the precise scattering from objects efficiently and stably. It was exemplified that this new method could reduce memory and computation time at the same accuracy by its application to the bistatic radar cross section (RCS) of sphere. Scattering from serrated edge plates was analyzed. The problem how the RCS reduction of serrated edge plate changes against straight edge plate was discussed in different angle range. The connection between the RCS reduction and incident frequency was also discovered. Results show that the RCS reduction of serrated edge plate increases sharply when the incident frequencies become larger, the RCS reduction effect in vertical polarization is greater than that in horizontal polarization. This conclusion can find its application to improve the stealth performance of aircraft.
Multirate digital phase generated carrier demodulation
Lan Tian, Zhang Chunxi, Li Lijing, Han Xiaojuan
2008, 34(05): 503-506.
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Based on the signal bandwidth in each phase generated carrier (PGC) demodulation procedure, a multirate demodulation scheme was proposed to solve the real time digital PGC demodulation problem at high sampling rate. The interfered output was analog-to-digital converted at high sampling rate to improve demodulation bandwidth and dynamic range. The procedures after frequency mixing and low pass filtering were down sampled and digital PGC demodulation computation was reduced. A digital PGC demodulation system was designed and implemented. The frequency mixing and low pass filtering procedures were implemented using field programmable gate arrays (FPGA) and the following procedures were implemented using digital signal processor (DSP). Real-time demodulation experiment verified that a test signal with 5kHz and 1rad was successfully demodulated at 1MHz sampling rate.
Helicopter rotor smoothing based on GRNN neural network and genetic algorithm
Liu Hongmei, Wang Shaoping, Ouyang Pingchao
2008, 34(05): 507-511.
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Considering traditional adjustment method without calculating possible nonlinear between rotor adjustments and fuselage vibration signals, a new rotor adjustment method based on general regression neural network (GRNN) and genetic algorithm was presented. GRNN network was employed to model the relationship between the rotor adjustments and the fuselage vibrations, whose inputs are rotor adjustment parameters and whose outputs are acceleration measurements along the three axes of rotor shaft and the fuselage. With helicopter vibration as objective function, genetic algorithm was used to make a global optimization to find the suitable rotor adjustments corresponding to the minimum vibrations. Flight test results indicate that proposed rotor adjustment method can minimize fuselage vibration at fundamental rotor frequency along the three axes, only in one or two adjustment flights, and that the neural networks may be updated to include new data thus allowing the system to evolve and mature in the course of its use.
Hierarchical knowledge base in intelligent pilot-s assistant system
Song Han, Chen Zongji
2008, 34(05): 512-515.
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To realize knowledge base of intelligent pilot-s assistant system during the full flight course, hierarchical architecture based on task decomposition was adopted. The hierarchical knowledge base was proposed: task-judging level, field-judging level and aiding-making level. Cooperative team combat mission of fighter aircraft was analyzed emphatically. And 14 sub-tasks were defined according to the flight phase, situation and objective. The sub-task, attack air target beyond visual range, was studied. The sub-task was disjointed by 5 fields on the time dimension or spatial dimension. Modules architecture of the hierarchical knowledge base was established by the expert system software tool C language integrated production system(CLIPS). The effectiveness and the feasibility of hierarchical architecture are demonstrated by the distributed real-time simulation system.
Method in image-s feature extraction and matching
Zhang Shaohui, Shen Xiaorong, Fan Yaozu
2008, 34(05): 516-519.
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To solve the problem of adaptability and accuracy in the field of image feature extraction and feature matching, the method of scale invariant feature transform (SIFT) was introduced. Firstly the characteristics of the SIFT method were analyzed by theory, and the SIFT method was implemented step by step on the visual studio 2005 platform; Then the features extracted by SIFT method were applied to match images on the criterion of nearest neighbor based on Euclidean distance. A suggestion value bound was given by comparing the matching result of different nearest ratio. At last the effect of the SIFT method was validated by the matching result of three different groups of images. The matching result shows that the features extracted by SIFT method are invariant to image scale, rotation and illumination change, and the matching accuracies are all equal or close to 100%. These results prove that the features extracted by SIFT method have excellent adaptive and accurate characteristics, which are useful for the fields of image recognition, image reconstruction, etc.
Multi-strategy GML application schema matching approach
Zhang Weiwei, Li Chao, Zeng Xiao, Xiong Zhang
2008, 34(05): 520-523.
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GML(geography markup language) application schema matching is a basic problem in the GML-based share of geography information. Combining the existing pattern matching algorithms and the characteristic of GML3.0 application schema, a multi-strategy GML application schema matching approach was proposed. Firstly, the input GML application schemas were transformed into the tree structure. The specific matching rules including linguistics and constraint were introduced which would help to compute the similarity between two elements, and then the two results were merged into element-level similarity. Secondly, the element-level similarity was modified by a structure-level matching algorithm based on similarity flooding theory. Finally, a mapping table of GML application schema elements was obtained. Experiment results show that the approach can effectively discovery the element similarity, and it can improve the matching result with a high degree of accuracy.
Numerical simulation of tractive performance for planetary rover vehicle wheel by discrete element method
Li Wen, Gao Feng, Jia Yang, Sun Peng
2008, 34(05): 524-528.
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The numerical simulation for wheel-soil interaction was conducted by discrete element method (DEM) where the grouser-sections of wheels were rectangle, rec-trapezia, and triangle respectively. The distribution of contact reaction for soil particles was analyzed in the granular scales when they are disturbed by different lugged-wheel configurations. The relationship between microscopic results of DEM and macroscopic parameters of tractive performance was built by means of coordinates transformation and algebraic summation. The formulae of soil thrust, motion resistance and drawbar pull were derived respectively in order to study the influence of grouser-section shape upon tractive performance of wheel. The calculated results show that the wheel with rec-trapezia-section grousers possesses the best tractive performance among the three kinds of lugged-wheel configurations in the same traveling condition.
Multidisciplinary optimization in earth observation satellite main parameters
Tan Chunlin, Pang Baojun, Zhang Lingyan, Huang Hai
2008, 34(05): 529-532.
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A model of multidisciplinary design optimization (MDO) was established for the system parameter design problem of an earth observation satellite. It takes the observation performance as the objective of optimization, while the design variables and constraints are dealt with five main subsystems including attitude and orbit control, power, structures, propulsion, payload, besides constraints made by launch vehicle and the analysis modules modeled by empirical formula. A multidisciplinary design optimization framework was established by using the collaborative optimization (CO) method, and exterior penalty technique was using to change the constrained question into an unconstrained question during system level optimization, so as to improve numerical difficulties in CO method application. The results show that the earth observation performance can be improved by this optimization method and the method was efficient. The modeling and optimization method of the work can be expected to apply to practical engineering satellite parameters design.
Method of any two-position alignment based on predictive filter for SINS
Gong Xiaolin, Fang Jiancheng
2008, 34(05): 533-536.
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Aiming at the initial alignment of strapdown inertial navigation system(SINS) with a large azimuth misalignment angle, the nonlinear mathematics model based on additive quaternion error(AQE) equations was established. And any two-position alignment method based on model predictive filter(MPF) and extended Kalman filter(EKF) was proposed. In this method, parts of inertial element errors were regarded as the model error, and estimated as part of the solution. The model error was not limited to Gaussian noise characteristics, and the algorithm could be implemented on-line to both filter noisy measurements and estimate state trajectories. The results of tests show that this method has better precision and faster convergence of all misalignment angles especially the azimuth one than that of EKF. Furthermore, this method improves the alignment-s real time by reducing the number of states.
Experiment of heat release rate of pool fire effect on water mist fire suppression
Yang Lijun, Liao Shengjie, Fu Qingfei, Wang Xiangdong
2008, 34(05): 537-540.
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In order to research on fire extinguishing characteristics and rules of water mist under different heat release rate conditions, seven heptane-pan fire of different sizes were applied to single-nozzle and four-nozzle fire extinguishing experiments in the compartment of 4.6m×3.3m×4m. Thermocouple tree and gas analyzer were used to measure flame temperature and oxygen concentration around the flame during the experiment. The characteristics rules of water mist fire extinguishing under different heat release rate conditions and change rules of flame temperature field during fire extinguishing were obtained respectively. The design and test standard method of water mist fire extinguishing system and the development criteria of water mist fire extinguishing products were provided from the experiment.
License plate location based on Tophat transformation and text texture
Zhu Chengjun, Pu Juhua, Gao Lei, Xiong Zhang
2008, 34(05): 541-545.
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Because the scene where license plate recognition system is located in is more and more complicated, license plate location method should have better performance. A new license plate location method based on Tophat transformation and text texture was introduced. First, Tophat transformation was applied to restrain background and eliminate variant illumination of image, and then binary operator and connected component analysis were applied. Second, the VPM(vertical projection map) of image was transferred to frequency space by DCT(discrete cosine transformation). The low frequency coefficients were used to reconstruct VPM. The reconstructed VPM was smoother, so region texture could be described essentially the wave crests and troughs number, statistic of reconstructed VPM. Last, pattern vectors were made up of low frequency component of frequency descriptors and statistic of reconstructed VPM, and were classified into license plate regions and non-license plate regions by SVM(support vector machine). Experimental results show that the method has good performance even when image has low quality and license plate is located in complicated natural scene.
Performance evaluation and comparison of 2 porous laminated plates
Lü Dong, Tao Zhi, Deng Hongwu, Li Haiwang
2008, 34(05): 546-550.
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A new form of porous laminated plate (PLP), model 161, was put forth, which had 50% pin-fin quantity increasing compared with its conventional counterpart, model 141. The 2 models were studied on their flow resistance and heat transfer characteristics by experiment and numerical simulation. A thermal radiation heating facility was employed to maintain the heat flux on the PLP upper external surface, and the actual heating rate was calculated by the enthalpy difference between the inlet and outlet of the coolant. The external surface temperatures were arithmetically averaged. It was found that the model 161 had 20% less flow resistance and 5% more heat transfer than the model 141. The numerical simulation results were in good agreement with the experiment for the flow resistance. However, the discrepancy for the heat transfer was significant and a maximum deviation of 30% in Nusselt number existed, although the variation patterns were quite the same.
Match analysis on two-stage turbo charging system of piston aero-engine
Xu Bin, Wei Ling, Zhao Peng
2008, 34(05): 551-554.
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To reach the motive force requirement of high altitude light aero-plane, a two-stage turbo charging system matching design analysis was performed for a turbo charging piston aero-engine. The software package of AVL boost was used to establish a theoretical analytic model of the supercharged prototype engine. The model was verified and validated though experiments. The model of two-stage turbocharging engine was set up on the basis of the model of prototype engine, and the matching calculates had been done. The characteristics of engine in different altitude above sea level were calculated, and the effects of engine major parameters for the performance were analyzed. The rule of the bypass valve regulating the two-stage turbocharging system was studied. The variation trend of high and low stage compressor-s total pressure ratio versus the different altitude was defined. The result shows that the two-stage turbocharging system can provide high boost pressure, which can be maintained the requested engine power. These work reaches the anticipated design object.
Design of fuzzy pulse width modulation controller with accuracy and energy retrenchment applied to spacecraft
Zhou Yinqiang, Xu Lianxin, Jiang Yuxian
2008, 34(05): 555-559.
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The fuzzy proportional differential (PD) pulse width modulation (PWM) controller which adopts PWM and fuzzy PD control was introduced into accurate and energy-retrenched control for attitude and orbit of spacecraft. PWM can convert on-off type control to relevant accurate linear control, and fuzzy PD control can implement two speedy and energy retrenched control processes with different consumed energy restricts. The performance demands on attitude control system were analyzed in target-capture and terminal-guidance phases of extra-atmospheric kill vehicle (EKV). Fuzzy PD-PWM controllers were designed and optimized to achieve the demands. The design of membership functions and fuzzy control rules, and the selection on parameters for optimization were discussed for those controllers. Genetic algorithms (GA) were used to optimize the membership functions of input fuzzy variables for expected demands. And the fitness function design for GA was explained. The simulations prove that the optimized controllers can respectively satisfy the demands on attitude control for EKV in different phases with accuracy and energy retrenchment.
Analytical calculation of focal spot size for lens antenna
Lü Shanwei, Zhang Yan, Yu Huilong, Li Yuying
2008, 34(05): 560-563.
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An analytical method was presented to calculate the focal spot size of the focal lens antenna. Firstly, the formulation for the 3dB focal spot size on the focal plane of the focal lens antenna was derived by Huygens-Fresnel principle. Then this formulation was simplified for convenience and the approximate expression was obtained. Secondly, the field distribution on the plane that parallels the focal plane was discussed. In order to demonstrate the accuracy and efficiency of this new method, a focal lens antenna at Ka band was designed and simulated as an example. Moreover, two focal lens antennas were fabricated for comparison. And these two lens antennas were measured by the planar-near-fields (PNF) method. Finally, the results obtained by the proposed method were compared with those of numerical method and measured data. It is found that the results of 3dB focal spot size computed by the approximate expression are in good agreement with the experimental data.
Numerical modeling of high strain compression of anisotropic elastic open-cell foams
Lu Zixing, Chen Xin, Zhang Jialei
2008, 34(05): 564-567.
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Based on the anisotropic irregular model, the compressive mechanical properties of low-density open-cell elastic foams were simulated by finite element analysis. The compressive stress-strain curves and elastic collapse strength were obtained in order to investigate the influence of anisotropic ratio, random degrees and relative densities on the mechanical properties. The results show that the deformation mechanism is different when loads are applied in different directions, and strut buckling becomes the main deformation mechanism at large compressive strains. A larger anisotropic ratio leads to larger elastic collapse strength along the cell rising direction and lower elastic collapse strength in the vertical direction. Meanwhile, the higher random degree causes lower stress-strain curves in both directions. When λ =1, the effective stress-strain curves well accord with the experimental curves.
Short fibre delayed self-heterodyne interferometer for ultranarrow laser linewidth measurement
Jia Yudong, Ou Pan, Yang Yuanhong, Zhang Chunxi
2008, 34(05): 568-571.
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Ultranarrow laser linewidth measurement using an shorter delay fibre to realize delayed self-heterodyne interferometer was described. The fundamental using delayed self-heterodyne to measure laser linewidth was analyzed, and the emulator was programmed based on the mathematical module. An experimental setup was constructed to measure subkilohertz laser linewidths, the experimental results agree well with the emulational result. On the basis analysis, the method of short fibre delayed self-heterodyne were presented and analyzed. By using the method, the measure error can be decreased greatly when the length of delay fibre shorter than six times laser-s coherence length. It is proved that method is an effective tool for measuring an ultranarrow laser linewidth, and it can reduce the length of fibre.
Texture image segmentation method based on wavelet packet transform and FCM clustring
Wu Yang, Yuan Yunneng
2008, 34(05): 572-575.
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A new method of optimal tree structure selection of wavelet transformation for image segmentation was presented. The standard pyramid-structure wavelet transform founded on the same recursive technique: only the low-pass outputs were used. It could not adjust the decomposition to accurate and efficient texture description. Although the wavelet packet transform provided a much more detailed analysis of the frequency content of a texture, it is often the case that areas which contain little or no frequency information are recursively decomposed. So the selection of optimal wavelet basis for texture characterization is very important. By introducing the validity measure for fuzzy clustering to the decision of wavelet decomposition structure, the presented algorithm simultaneously performs the adaptive wavelet decomposition and the texture feature classification, moreover it adaptively chooses the wavelet decomposition structure and depth. Compared with the wavelet packet decomposition, the algorithm reduces the computational burden, while obtains satisfactory segmentation results.
Functional-driven resource aggregation:method and its implementing
Guo Haoming, Ma Shilong
2008, 34(05): 576-579.
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A dynamic and non-persistent mapping resource aggregation mechanism was proposed, through which functional-driven workflow system was formed in SOA (service oriented architecture)environment for application aggregation requirement. In the mechanism, services in application model were not static component. Application process model and task were separated and functions needed by application were concerned. The mechanism consisted of three layers: In the bottom layer, service information collection was created to aggregate all services of same functionality needed by application; In the middle layer, function attributes of services was defined; In the top layer, application context was created to realize constrains between services and binding conditions while implementing task. In the model, logic data was adopted to maintain data relation between services for heterogeneous service interfaces. Through the mechanism, application was composed by functions needed. A workflow system based on the mechanism, NGGWf (national geology grid workflow),has been applied in geologic applications in NGG(national geology grid) environment.
Comparation analysis of fill rate and backorder
Cheng Hailong, Kang Rui, Wei Yi, Qu Lili
2008, 34(05): 580-583.
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In order to solve the problem that how to choose the part level measuring parameter of supply support efficiency in spare supply provisioning, the mathematics means, physics means, the obtaining difficulty in practical use and the relationship of the same systemic efficiency measuring parameter of the fill rate and backorder based on the origin of the two parameters were analyzed, and then the difference and the contact of the two were observed. The application range of the fill rate and backorder was compared and validated through the application case, which is based on the METRIC model with the considering of the cost affection. The results show that the spare backorder is more exceeding than the spare fill rate in achieving the supply programming, while the spare fill rate is better in scaling the management of spare supply.
Three-dimension numerical simulation of working process of space plasma sail
Yao Jie, Tang Haibin, Wang Haixing, Liu Yu
2008, 34(05): 584-586.
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Using three-dimension model, the hybrid particle in cell method was used to simulate the interaction between the inflated magnetic field and solar wind. The interaction between solar wind particles and dipole magnetic field produced by coil was studied after the plasma injecting into the dipole magnetic field. The changing of solar wind and magnetic field was compared when the plasma was injected with different velocity. It is shown that the bow shock like-structure caused by the interaction between solar wind and dipole magnetic field appears at the area where the magnetic pressure and the dynamic solar wind pressure balance each other. The magnetic field inflates when high-energy density plasma was injected into the dipole magnetic field, then the magnetic field expels the solar wind particles outward. The bow shock like-structure changes and it increases the cross area with the solar wind. It is shown that the bigger the velocity of injected plasma, the more clear the magnetic field inflation and the stronger the interaction with solar wind.
Implementation approach to information integration between PDM and ERP systems
Qiao Lihong, Zhang Yizhu
2008, 34(05): 587-591.
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An information conversion and integration method between product data management(PDM) systems and enterprise resource planning (ERP) systems was presented. Based on the information in PDM and ERP systems, an integrated information model was built to describe the information of materials, product hierarchical structures and resources. The information transformation and data synchronization between the two systems were addressed by developing a conversion mechanism, with which an engineering bill of materials(BOM) can be converted to manufacturing BOM via process planning BOM, so as to achieve information semantic unification between the two systems. The mechanism consisted of four BOM structural conversion operators including composition, deletion, reorganization and decomposition, and two BOM property mapping methods of inheriting and deriving. The implementation of the proposed method was illustrated with an application practice of information integration between a PDM system and an ERP system in a specific enterprise. This integration method provides an effective way for further study of PDM and ERP integration.
Computational effects of ice accretion on aircraft longitudinal stability and control
Wang Mingfeng, Wang Lixin, Huang Chengtao
2008, 34(05): 592-595.
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A computational method was developed to predict the effects of airframe icing on aircraft flight dynamic characteristics according to atmospheric conditions, aircraft characteristics and flight conditions. Ice accretion scaling was performed by means of heat-transfer balance analysis, and aerodynamic model of iced aircraft was built by means of stepwise linear regression, the aerodynamic parameters due to ice accretion were computed by this model. The agreement of the computation results with the flight data indicates this method could be used to estimate the aerodynamic parameters at the analyses of longitudinal stability and handling quality. The penalties of aircraft longitudinal stability and control due to ice accretion on different region were investigated using this method. The results of computation demonstrate that the severe degradation of aircraft aerodynamic performance due to ice accretion may affect longitudinal stability and handling quality significantly, and endanger the flight safety.
All-fiber laser radar at 1.55μm for speed measurement
Ma Zongfeng, Zhang Chunxi, Wang Xiaxiao, Wang Jiqiang
2008, 34(05): 596-599.
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Strict optical alignment is essential for conventional coherent laser radar to match the local oscillator (LO) and signal modes. The scheme and system design of simple, continuous-wave (CW) coherent laser radar at 1.55 μm for speed measurement were presented. The system was based on all fiber instruments. A polarization-independent fiber-optic circulator and a Cassegrain telescope were used as the monostatic optical antenna. The fiber mixing technique of the receiver, the coupling efficiency between antenna and single-mode fiber (SMF) for spatial light, signal detection, digital data acquisition and processing were discussed. The experimental results indicate that the laser radar system has good robustness to random fluctuation noise of spatial light. In addition, the interference fringe visibility and the performance of the laser radar system are enhanced greatly. The speed resolution is less than 0.5mm/s, and the output nonlinearity of this laser radar is less than 0.1％.
Coding technology in PDM oriented to automobile manufacturers
Wang Su, Guo Zhifeng, Yan Lijuan
2008, 34(05): 600-603.
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From the automobile manufacturers- informationization process, the design method and application were introduced. A kind of coding algorithm applied to automobile manufacturing enterprises on the basis of analysis of material coding method and production features of automobile manufacturing enterprises, and the model of material coding system and the integration plan of product data management(PDM) system according to this algorithm were designed. Finally, based on PDM software SmarTeam, a coding system was developed and a case was analyzed in the system, which verified the feasibility of the algorithm and model.
United algorithm base of multi-language machine translation system:difference function
Hu Yue, Gao Qingshi, Gao Xiaoyu
2008, 34(05): 604-608.
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In the multi-language machine translation system based on semantic linguistic theory, in order to realize the translation between different natural languages with one algorithm and one program, the ‘difference function’ was introduced. The function of ‘difference function’ is to hide the representation differences among various natural languages about a language function, so that translation process is independent of concrete languages and the multi-language translation machine system can easily deal with language content with the united algorithm and program, which requires different treatment in different language. Taking the difference of radix representation function as an example, the role of the difference function and the application of such function in multi-language were discussed.
D-optimal six position testing method for dynamically tuned gyro
Fu Li, Liu Wenli
2008, 34(05): 609-612.
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The construction of a D-optimal six position experimental design for the two-degree of freedom dynamically tuned gyroscope was presented, in order to improve estimate accuracy of the acceleration-insensitive drift rate and acceleration-sensitive drift rate coefficients of the assumed error model at reasonable experimental cost. The basis idea is to choose six measurement positions to build a D-optimal experiment by applying the symmetric separate design method of orthogonal design. In order to test the efficiency of D-optimal six position experimental design, a series of lab tests were conducted to compare the coefficients solution computed with a usual experimental design in ANSI/IEEE Std 813-1988 and the D-optimal six position experimental design. Tests results show that the D-optimal six position experimental design provides at least same accurate estimates of the acceleration-insensitive drift rate and acceleration-sensitive drift rate coefficients compared to a usual experimental design in ANSI/IEEE Std 813-1988 at less experimental cost .

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