A Measuring System With an Additional Channel for Eliminating the Dynamic Error

Abstract

Abstract. The present article views a measuring system for determining the parameters of vessels. The system has high measurement accuracy when operating in both static and dynamic mode. It is designed on a gyro-free principle for plotting a vertical. High accuracy of measurement is achieved by using a simplified design of the mechanical module as well by minimizing the instrumental error. A new solution for improving the measurement accuracy in dynamic mode is offered. The approach presented is based on a method where the dynamic error is eliminated in real time, unlike the existing measurement methods and tools where stabilization of the vertical in the inertial space is used. The results obtained from the theoretical experiments, which have been performed on the basis of the developed mathematical model, demonstrate the effectiveness of the suggested measurement approach.

A Kalman Filter-Based Algorithm for Measuring the Parameters of Moving Objects

“…As it is mentioned in [9], if the dynamic error is determined only on the basis of the measuring procedure described above, the accuracy is not sufficient. The motion of the moving object initiates not only basic but also secondary disturbance processes of unpredictable behaviour for the sensitive elements of the measuring instruments in the additional channel.…”

“…In compliance with the basic principles of the above mentioned approach, a specific system for measuring the roll, pitch, heel and trim of a ship is developed in [9]. It overcomes the disadvantages of the existing measuring instruments since it is based, on one hand, on a very simplified mechanical module, and on the other hand, on the advanced achievements in the area of nanotechnologies, microprocessor and computer equipment.…”

“…Within the mechanical module of the system the accelerometers are positioned in such a way that an algorithm for determining the dynamic error along the two measuring coordinates (heel and trim) can be developed from their output signals. This algorithm is described in detail in [9]. The additional measuring channel operates in parallel with the basic one so as to provide a possibility for eliminating the dynamic error from the measurement result in real time.…”

“…The characteristics of this algorithm fit very well into the solution of a number of problems arising in the process of accuracy optimization of the measuring instruments that define the parameters of all moving objects listed above [10]. In that case the algorithm will be developed in the context of the set objective, which is related to the improvement of the dynamic accuracy of the measuring system presented in [9]. This procedure is part of the additional channel and aims at eliminating the influence of a number of secondary disturbances on the measurement result.…”

“…[7,8], thus limiting, to a great extent, their application. A complete solution to those problems can be found by means of the concept proposed in [9], where unlike the existing measuring methods and tools that use vertical stabilization in the inertial space this approach is based on methods eliminating the dynamic error in real time. The proposed concept for modelling measuring instruments and systems of this type overcomes, to a great degree, the above listed disadvantages.…”