Operating principle of modern ballistic gravimeters is based on the measurement of motion parameters of a macroscopic test body or a cloud of cold atoms in the field and calculation of free-fall using the measured motion parameters from the test body motion equation. There are about 200 transportable ballistic gravimeters in the world, the best of which feature uncertainty of a few units of 10-8 ms-2. Metrological assurance system for absolute gravimeters is being developed. Improvements in absolute gravimeters will allow their use on moving platforms.

The work presents the results of the measurements of absolute gravity value g obtained over four field seasons in 2010-2013 at marine expeditionary station of Pacific Oceanological Institute at Shults Cape of Gamov peninsular (42.58°N, 131.15°E, Russia). The measurements revealed that during the first year the absolute g at the measurement point increased by 5.1 μGal, and during the second year, by 3.2 μGal. The auxiliary point No. 2 located 46 m below the main point No. 1 was founded in 2012 to create a gravimetric test site for calibration of the tidal gravimeter g-Phone.

Airborne gravimetry for geodetic purposes such as geoid determination and global geopotential models requires good bias stability, as well as good performance in turbulence for large-scale national projects. DTU-Space has since many years carried out large area airborne surveys over polar, tropical and temperate regions. Recently we have started flying two gravimeters (L&R and Chekan-AM) side by side for increased reliability and redundancy in several surveys. In the paper we will give some examples of recent survey results, confirming accuracies in the 1 mGal range for a well-controlled Danish flight test, and around 3 mGal for intercomparisons of Chekan and L&R results in Nepal, one of the most challenging field survey regions on the Earth. We also indicate the good agreement between airborne gravity and GOCE data in Nepal, and outline the use for improved geoid determination.

Based on laser gyros and quartz flexure accelerometers, Beijing Institute of Aerospace Con-trol Devices has developed the prototype of Laser Strapdown Airborne Gravimeter (LSAG). The hardware improvements and the design of post-processing software are presented, and field test results of the system on the aircraft and oceanic vessel during 2013 and 2014 are given. Field test results showed that the internal accord accuracy after level adjustment was about 1mGal, demonstrating that LSAG has the abilities to implement airborne gravity sur-veys, and has the potential for marine gravity surveys.

A method for calibration of the Chekan-AM gravimeter, the one that does not require any bench testing equipment, is proposed. Special software providing for automatic calibration and processing of the calibration results has been developed. The experimental verification of the proposed techniques has confirmed the feasibility of periodic calibration of the Chekan-AM gravimeter by the new method.

The paper considers the problem of improving the accuracy of gyro stabilized system of airborne gravimeter during the survey. To reduce the stabilization error, a time-varying correction algorithm is proposed, which accounts for the heading error during the maneuver. Performance of stabilization system is studied with different models of heading errors. The proposed algorithm demonstrates critically reduced transient time as compared with the traditional time-invariant algorithm.

Nowadays the importance of airborne gravity surveys in polar areas has urged the designers to modify hardware and algorithmic solutions for the airborne gravity instruments, because platform type gravimeters such as GT-2A in standard implementation cannot be used in latitudes over ±75°. The solution is the use of multiantenna GPS receiver as a sensor of trajectory and aiding angular data. The paper focuses on real-time data fusion and postprocessing using multiantenna GPS receiver.

The possibility to use a well-known inertial geodetic method for determining one of the parameters of anomalies of the gravitational field of the Earth - plumbline deviation at high latitudes is considered. Solution of the problem is proposed in the framework of designing a specialized integrated system comprising a precision inertial unit and two-antenna GNSS receiving equipment with long antenna base. The algorithms for solving the problem, the accuracy estimation obtained using a simulation study in MATLAB (Simulink) and the results of sea trials of the GPS compass designed by CSRI Elektropribor, JSC are presented.

The paper focuses on the problem of gravity anomaly determination by airborne gravimetry data. To solve the problem, nonlocal information on the Earth gravity field is needed, usually provided by one of the Earth’s global gravity field models. The possibility of using spherical wavelet expansion for combining airborne gravimetry and global data is studied. Combination algorithms based on optimal estimation methods are developed and tested using Arctic airborne gravity survey data and EGM 2008 global model.

The possibility of using adaptive nonlinear filtering in solving airborne gravimetry problems with uncertain parameters of the model for estimated gravity anomalies is considered.

A map-aided navigation method is considered. The main features of this method are discussed; an overview of the algorithms used to solve navigation problems is given. Considerable attention is focused on the algorithms based on the use of nonlinear filtering, which make it possible to not only formulate and solve the problem of algorithm design, but also provide a background for accuracy analysis.

A mathematical model of a gyro stabilization system for an air-sea gravimeter is considered. The stabilization system is based on fiber-optic gyroscopes (FOGs) with accelerometer correction loops. The aim of the experimental studies was to estimate attainable accuracy of the FOG-based gyrostabilizer breadboard. In these experiments, the gearless servo system loop included floated integrating gyroscopes, whereas FOGs, mounted on the inner ring of the gyrostabilizer, were used to calculate dynamic stabilization errors caused by disturbances of the gearless servo system at rocking. The calculated dynamic stabilization accuracy obtained with the FOG data was evaluated with the use of autocollimation measurements.

In this paper presented mathematical model of the aviation gyro gravimeter eq. (9) – that allows to obtain values of acceleration of gravity on the surface of the reference ellipsoid. From equation (10) one can obtain gravity anomalies. Introduced model allows to conduct simulations of aviation gyro gravimeter in conditions that are close to the conditions of a flight. To do this, in mathematical model were included both forward and angular vibrations of the gravimeter's basis. In practice, these vibrations can be measured using MEMS gyroscopes. Fundamental difference of the proposed model from the known models is using of angle sensors of the gyroscope to get the gravity anomaly.