4 results about "Absolute gravity" patented technology

The application discloses a steel pipe pile sinking verticality real-time closed-loop control system based on a gravity reference, and relates to the technical field of pile foundation engineering construction. The application takes absolute gravity as a unified reference, obtains offset data through full-pile-body multi-section coaxial measurement, solves pile body deflection deformation, and realizes hierarchical collaborative closed-loop control of preferential deviation correction of the middle and lower sections of the pile body. The application has the following advantages. A full-pile-body coaxial measurement module is arranged along the inner wall of the steel pipe pile, cooperates with a gravity reference establishment module penetrating the whole section of the steel pipe pile, obtains offset data of multiple sections of the whole section of the pile body relative to the unified gravity reference, and then a pile body deflection solving module is used to obtain the real deflection deformation curve of the whole section of the pile body. The application breaks the industry's common cognitive limitation that the steel pipe pile is an ideal rigid body and that the verticality of the pile top represents the verticality of the whole pile body, and effectively solves the industry's pain point that the existing technology cannot identify and cannot intervene in the hidden deflection deformation of the middle and lower sections of the pile body in advance.

The invention discloses a field programmable gate array (FPGA) time sequence control algorithm for a marine atom gravimeter, and relates to the technical field of high-precision gravity matching navigation.According to the system, a front-end optical subsystem, a rear-end optical subsystem and an upper computer data processing module are set up, high-precision synchronous control over multiple paths of signals is achieved in combination with an FPGA, and an interference fringe resolving method for Bayesian inference cosine estimation is adopted, so that high-precision synchronous control over the multiple paths of signals is achieved. And the synchronization performance and the gravity measurement precision of each module of the atom marine gravimeter are effectively improved. According to the method, the external coincidence precision of gravity measurement is improved to 0.8 mGal while the stability of the system is ensured, the requirements of ocean dynamic absolute gravity measurement are met, and the method can be widely applied to the fields of resource exploration, passive navigation, geophysical research and the like.

The present application belongs to the field of geodetic survey and geophysical exploration, and discloses a real-time gravity potential measurement method and device combining unmanned aerial vehicle and Beidou, which comprises the following steps: step 1: system calibration; before the start of flight task execution, the unmanned aerial vehicle is parked on a ground calibration reference point with known gravity potential for static observation; step 2: real-time Beidou data acquisition; the unmanned aerial vehicle flies according to a preset route, and each trajectory point is observed for a certain time; step 3: real-time receiver clock error solving; an observation equation based on the current trajectory point is established to solve the three-dimensional coordinates and GNSS receiver clock error of the current trajectory point; step 4: gravity potential solving; the absolute gravity potential value of any point on the flight trajectory of the unmanned aerial vehicle is solved in combination with the receiver clock error obtained during the flight calibration of the unmanned aerial vehicle in step 1; and step 5: data output and mapping. The present application completes high-precision gravity potential measurement on a mobile platform, and breaks through the limitation of traditional gravity measurement relying on static observation or ground layout.

The invention provides an absolute gravity measurement data tamper-proofing method and system based on a geophysical law and chained Hash. The method comprises the following steps: continuously acquiring actually measured gravitational acceleration values, space coordinates and timestamps of a plurality of measurement points along a preset measurement path; calculating a gravitational acceleration residual error of each measuring point; performing Hash operation on each measuring point to generate a chain type joint feature code; taking the chained joint feature codes of all the measuring points as leaf nodes, constructing a Merkle binary tree and obtaining root hash; writing the data into a block chain for evidence storage; and when data verification is needed, the steps are executed again to obtain a new root hash, the new root hash is compared with the stored root hash, and if the new root hash is compared with the stored root hash, it is judged that tampering exists in the measured data. According to the method, the geophysical law is introduced as an endogenous security element, and the cryptography and block chain technology are combined, so that attacks such as single-point data tampering and measuring point sequence rearrangement can be effectively detected, and full-link security guarantee from a physical source to digital evidence storage is provided for high-value gravity measurement data.