9 results about "Gps measurement" patented technology

The invention discloses an RTK (Real Time Kinematic) and IMU (Inertial Measurement Unit) fusion state estimation method based on adaptive weight. According to the method, an observable state estimation system is established by using two RTK-GPS antennas and an IMU device based on a self-adaptive Kalman filtering framework. By constructing a proper antenna layout, the connecting line for connecting the two GPS antennas is not parallel to the acceleration vector, so that the observability condition is met, and the attitude error caused by gyroscope drift is effectively compensated. Compared with a traditional single-GPS fusion scheme, high-precision estimation of the three-dimensional attitude and position can be achieved without an additional attitude measurement device such as a magnetic compass, a self-adaptive covariance estimation strategy based on a sliding window is introduced, the GPS measurement noise level is evaluated in real time, the fusion process is endowed with a high weight only when GPS information is reliable, and the fusion precision is improved. The method effectively improves the robustness of the system, is suitable for unmanned ship navigation tasks in various water area environments, and has a wide engineering application prospect.

The invention belongs to the field of error calibration, and particularly relates to a submerged-load ultra-short baseline underwater calibration system and an installation deflection angle calibration method. The invention discloses a submerged-load ultra-short baseline underwater calibration system and a calibration method thereof for an installation deflection angle, and overcomes the limitation that a traditional calibration method depends on high-precision GPS positioning information. The system comprises a submerged ultra-short baseline subsystem installed on a submersible vehicle and two seabed reference subsystems arranged on the seabed. According to the implementation scheme, a submersible vehicle carries out differential positioning on two seabed references along a preset track, carrier position parameters are eliminated, and a submersible ultra-short baseline installation deflection angle calibration model is established; based on the matrix decomposition theory, an observation equation of each installation deflection angle is constructed, and the installation deflection angles are obtained through an alternating iteration estimation algorithm. Through the method, the installation deflection angle can be estimated without GPS measurement information, and the method is suitable for a submerged platform executing underwater tasks for a long time.

The present application belongs to the field of error calibration, and particularly relates to a submerged ultra-short baseline underwater calibration system and a calibration method for installation angle. The present application discloses a submerged ultra-short baseline underwater calibration system and a calibration method for installation angle, and overcomes the limitation of traditional calibration methods which depend on high-precision GPS positioning information. The present application comprises a submerged ultra-short baseline subsystem installed on a submarine, and two seabed reference subsystems arranged on the seabed. The implementation scheme is as follows: the submarine performs differential positioning on the two seabed references along a preset track, eliminates the carrier position parameters, and establishes a submerged ultra-short baseline installation angle calibration model; based on matrix decomposition theory, an observation equation for each installation angle is constructed, and the installation angle is obtained through an alternating iterative estimation algorithm. Through the present application, the installation angle can be estimated without GPS measurement information, and the present application is suitable for submerged platforms that perform long-term underwater tasks.

This invention relates to the field of architectural observation deck construction technology, specifically to a method for constructing a complex, nonlinear, multi-curved high-altitude observation deck. The method includes the following steps: construction of a hyperbolic accessible roof with landscape stone paving and micro-planting; installation of fair-faced concrete GRC panels under the eaves of an irregularly shaped, ultra-long, cantilevered, complex curved surface; construction of an ultra-high, inclined, irregularly shaped glass curtain wall in the confined space under the eaves; and construction of a single-curved, stacked, wingspan-shaped dry-hanging stone staircase. This method utilizes BIM technology combined with total station and engraving machine technology for precise measurement, design refinement, and construction control of each part. By combining the BIM model with on-site 3D scanning results and GPS measurement instruments, it ensures that the construction elements accurately correspond to their theoretical models and achieve integration with the natural environment. This invention achieves a high degree of consistency with design goals and a landscape-integrated design, providing strong support for the harmonious coexistence of the high-altitude restaurant and the natural environment, and ensuring the high precision and high quality of the external panel curtain wall system.

The invention provides a method for reducing boulder yield by deep hole blasting, which belongs to the technical field of blasting and comprises the steps of field measurement, blasting analysis, blasting parameter determination, field hole arrangement, gps hole site data measurement, computer-assisted blasting design, drilling construction, hole inspection, field charging, line connection, blasting, gps positioning of a reserved covering layer and blasting completion. The method is easy to operate, and special construction equipment is not needed. And a covering layer is reserved in the digging and transporting link, so that the blasting cost is reduced. The method comprises the following steps: firstly, reducing a resistance line and increasing a hole distance in the aspect of blast hole layout, so that the useful work released by explosives is further expanded to a certain extent; and secondly, the covering layer is reserved, so that excessive charge caused by ultra-depth is reduced, engineering practice shows that the method is very effective, a very good effect is achieved when f is equal to 5-17, the boulder rate of a muck pile formed by blasting is obviously reduced, loading and transportation are convenient, and the working efficiency is improved accordingly.

This invention discloses an adaptive weighted RTK-IMU fusion state estimation method. Based on an adaptive Kalman filter framework, this method establishes an observable state estimation system using two RTK-GPS antennas and one IMU device. By constructing an appropriate antenna layout, the line connecting the two GPS antennas is not parallel to the acceleration vector, thus satisfying the observability condition and effectively compensating for attitude errors caused by gyroscope drift. Compared to traditional single-GPS fusion schemes, this invention achieves high-precision 3D attitude and position estimation without requiring additional attitude measurement devices such as magnetic compasses. The method introduces an adaptive covariance estimation strategy based on a sliding window to evaluate the GPS measurement noise level in real time, assigning higher weights to the fusion process only when GPS information is reliable, effectively improving system robustness. It is applicable to unmanned surface vessel navigation tasks in various aquatic environments and has broad engineering application prospects.

The application provides a method for realizing precise measurement of a fixed direction antenna system based on multiple spatial measurement technologies, aiming at the actual situation that multiple sets of feeder systems are installed in a structure closed feeder house, and comprehensively using a static GPS measurement system, a total station measurement system, a laser tracker measurement system and a digital industrial photogrammetry system, the total station measurement system is arranged in the feeder house, indoor measurement reference points and outdoor measurement reference points are set, unification of the indoor measurement reference points in the structure closed feeder house and the outdoor measurement reference points of an antenna main reflector is realized, measurement error of a multi-beam antenna system coordinate system is reduced, and the precision of measurement and adjustment of the antenna main reflector and the feeder system is improved; the precise measurement and adjustment of the spatial absolute position and attitude of multiple sets of feeder systems based on the unified reference of the fixed direction antenna system in the structure closed feeder house is realized, and the measurement and adjustment efficiency of the spatial absolute position and attitude of the feeder system is improved.

Method for estimating a delay of a GPS measurement in a moving vehicle compared to at least one recorded vehicle dynamics parameter, characterized in that a) the first vehicle dynamics parameter or a parameter derived therefrom is compared with a first threshold, b) if the first vehicle dynamics parameter or parameter derived therefrom has remained below the first threshold for a first predetermined period of time, but subsequently exceeds the first threshold for a predetermined second period of time, c) a reference time is determined and at least from this reference time the first vehicle dynamics parameter or a parameter derived therefrom is compared with a reference parameter derived from the GPS measurement and the delay of the GPS measurement is estimated from this.

The THz SAR two-dimensional self-focusing imaging algorithm comprises the following steps in sequence: a THz SAR echo signal model is established; a residual video phase term and an inclined phase term are removed; a distance direction nonlinear phase error is estimated; distance direction compensation is performed based on the estimated nonlinear phase error; a distance compressed echo signal is obtained after distance direction compensation; a distance direction coarse compensation is performed on the distance compressed echo signal; a range migration correction is performed on the distance direction coarse compensation echo signal; a residual phase error in the azimuth direction is estimated; azimuth direction fine compensation is performed based on the estimated residual phase error; azimuth direction fine compensation is performed on the azimuth direction fine compensation echo signal; and a THz-SAR focusing image is obtained after azimuth direction compression. In the present application, the distance direction nonlinear phase error and the azimuth direction motion phase error are estimated and compensated to obtain a high-resolution THz-SAR focusing image; and compared with directly using the self-focusing algorithm, the joint use of IMU / GPS measurement data and the MEA self-focusing algorithm can reduce the amount of calculation.