In this paper, we propose an algorithm for tuning both the kinematic and measurement noise Variance–Covariance (VCV) matrices to produce a more robust and adaptive Kalman filter. The proposed algorithm simultaneously considers both observation outliers and abrupt changes. This algorithm may be divided into two basic parts: 1. Robust estimation, from which the position components of the filtering estimates and the equivalent weight factor matrix can be obtained; and 2. Adaptive estimation, from which the adaptive kinematic noise VCV tuning matrix is calculated. To demonstrate the efficiency of our algorithm, we process a set of kinematic Global Positioning System (GPS) data received from a rover mounted on an aeroplane. The processing results are found to be very satisfactory, with observation outliers and abrupt changes detected and dealt with accordingly. The detailed calculation procedure for the adaptive VCV tuning matrix is also described.
The blasting seismic waves generated by tunnel blasting will have an adverse effect on adjacent buried pipelines, which increasing the difficulty of subway construction. In this paper, taking the section of blasting excavation in Dalian Metro Line 1 as the engineering background, the attenuation law of blasting seismic wave in the soil and the vibration response of the buried pipeline are systematically studied by means of field measurement and numerical simulation. The deformation monitoring of the pipeline shows that the time curve of the pipeline and the surface settlement are distributed exponentially, and the trend of them is the same. The attenuation law of seismic wave obtained by numerical simulation is basically consistent with the measured results, which indicates that it is feasible to study the blasting vibration effect by numerical simulation. The Sa Rodolfo J Ki prediction formula is established according to the measured data, which can reflect the propagation law of the blasting seismic wave. It can provide some basis for the construction of subway tunnels at the subsequent stage.
Aiming to investigate the connection between camera structure and optical systems, a comprehensive analysis needs to be performed for the airborne camera. An integrated analysis method was proposed to design and analyze optical and mechanical structures. Based on the designed small airborne camera, the impact of microvibration on the optical performance of the airborne camera was studied by integrated optomechanical analysis. In addition, the change of optical surface accuracy was analyzed. First, static and dynamic analysis of the designed airborne camera was performed to verify the stability of the camera structure and obtain the data for integrated optomechanical analysis. Then, a calculation method for rigid body displacement was proposed, and the impact of rigid body displacements on the optical system was analyzed. To evaluate the change of surface accuracy, the parameters root mean square (RMS) and peak to valley (PV) were calculated by fitting the surface distortion data. Based on the Zernike polynomial coefficients, the response of the optical system was calculated and analyzed utilizing ZEMAX to analyze the impact of microvibration on the optical performance of the airborne camera. The analysis results show that microvibration has no significant impact on optical performance of the designed small airborne camera. Finally, the analysis results were verified through experiments.
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