Temperature sensitivity compensation of pressure sensor considering its nonlinearity is crucial to obtain a highly accurate measurement. Unfortunately, various software methods are known to have some drawbacks, thus a large number of calibration points is necessary to model the sensor response properly. This paper aims to present a new compensation method that features the utilization of common response of the given type of sensors and the reduction of particular sensor calibration data set, which subsequently reduces the duration of necessary experiments. Mathematical formulas, which are the basis of a solution, are derived from the sensor general model. Two cases have been considered and analyzed theoretically: iterative solution with sensor response, and noniterative with sensor reproducing function. The method is experimentally verified using two sets of sensors. There is a tenfold increase in accuracy after compensation. In addition, the practical limitation of achievable accuracy by full individual calibration in the given instrumentation is estimated. The cost of simplification increases the remaining error by about 50%. Hence, the advantage is the reduction of acquisition time more than by half. The achievable accuracy is about 0.01% full scale (FS). The results demonstrate that the proposed compensation method is valid for high-accuracy measurements. Furthermore, the comparison of various cases confirms the validity of sensors similarity assumption and correctness of a theoretical analysis presented in this paper.

Purpose: This paper aims to present a vision-based method for determination of the position of a fixed-wing aircraft that is approaching a runway.Design methodology/approach: The method determines the location of an aircraft based on positions of precision approach path indicator lights and approach light system with sequenced flashing lights in the image captured by an on-board camera.Findings: As the relation of the lighting systems to the touchdown area on the considered runway is known in advance, the detected lights, seen as glowing lines or highlighted areas, in the image can be mapped onto the real-world coordinates and then used to estimate the position of the aircraft. Furthermore, the colours of lights are detected and can be used as auxiliary information.Practical implications: The presented method can be considered as a potential source of flight data for autonomous approach and for augmentation of manual approach.Originality/value: In this paper, a feasibility study of this concept is presented and primarily validated.

This paper presents an attempt to determine the dynamic properties of a measuring system based on total pressure measurement with the use of a Pitot tube and a semiconductor pressure transducer. The presented research uses computed fluid dynamics (CFD) simulation and real data from the pressure measurement system for determination of the dynamical model of the Pitot tube with the transducer. An identification algorithm is applied to the data from the simulation, and the model in the form of a transfer function is an identification result. The oscillatory behavior is detected, and this result is confirmed by frequency analysis of the recorded pressure measurements. One of the resonant frequencies is the same in both experiments, but the second is slightly different. The identified dynamical models permit the possibility to predict deviations caused by dynamics and to select the appropriate tube for a particular experiment.

The response of a temperature sensor in a gas stream depends on several heat transfer phenomena. The temperature of the thermocouple’s hot junction in the hot stream is lower than the measured temperature, which causes a measurement error. Compensation for this error and interpretation of the values indicated by the temperature sensor are possible by using a sensor dynamics model. Changes over time of the hot junction temperature as well as the entire thermocouple temperature in a stream are solved using the finite element method. Fluid flow and heat transfer equations are solved for a particular sensor geometry. This article presents a method for identifying a temperature sensor model using the results of numerical modeling of the response to temperature changes of the fluid stream, in which the input and output signal waveforms are recorded and then used by the estimator of a model coefficient. It is demonstrated that the dynamics of a bare-bead thermocouple sensor are well-described by a first-order transfer function. The proposed method was used to study the influence of stream velocity on the reaction of two sensors differing in the diameter of the wires, and the effect of radiative heat transfer on the model coefficients was examined by enabling and disabling selected models. The results obtained at several calculation points show the influence of the stream outflow velocity and selected geometric parameters on the value of the transfer function coefficients, i.e., transfer function gain and time constant. This study provides quantitative models of changes in sensor dynamics as functions of the coefficients.

The speed of a rotor or rotors of a turbine engine is important information on its operation. Due to the specific conditions, in which the measurement is taken in a turbine engine, which in particular applies to small engines that are becoming increasingly popular in manned and unmanned aviation, the most universal detector is the detector using the phenomenon of eddy currents. This article presents the developed detector system solution. The correct operation of a detector is conditional upon the possibility to detect the presence of a blade in the detection field in a reliable manner, while maintaining the resistance to interference. The developed system is resistant to changes in parameters due to the use of a differential system consisting of two detector coils connected in a bridge circuit, a rectifier circuit with filters acting as a demodulator and a comparator. The system works with a microprocessor performing data processing functions. The executed functional model was tested in a laboratory, which enabled to determine its characteristics in several configurations and to confirm its correct operation.