Piotr Gazda

• Doctor of Philosophy
• Professor (Assistant) at Warsaw University of Technology

This study enables justified selection of suitable sensors for the extended cross-float method for the calibration of piston gauges. Three sensor types were tested: a triangulation laser sensor, a capacitive sensor, and a high-precision accelerometer. The extended cross-float method is employed to avoid determining the equilibrium point between int...

This article presents a study on the metrological properties of smartphone magnetometers and their application in determining the correct shoe size. The research focuses on using magnetometers in smartphones to measure the magnetic field generated by magnetic markers placed inside shoes. To measure foot dimensions, smartphone embedded position sens...

Measuring nonlinearity (linearity error) in high-resolution electronic balances, including microbalances, is challenging. Today's electronic balances are usually characterized by a small linearity error (with tolerance limits for nonlinearity specified by manufacturers in the order of several elementary divisions), and all criteria for measuring no...

Robotic disassembly of hard disk drives during their recycling process is a promising technology with significant ecological importance and high economic profitability. However, the efficiency of the robotic disassembly of screws in the cost-efficient process using the robotic system in the selective compliance assembly robot arm configuration is h...

Deadweight piston gauges are vital for metrology and calibration, with their effective area traditionally determined through labour-intensive methods or precise geometric measurements. This paper introduces an extended cross-float method that simplifies effective area determination by avoiding detailed equilibrium point adjustments. The proposed me...

Paper presents utilization of Finite Element Method (FEM) for analysis of usefulness of shoe size assessment method, based on magnetovision measurements. Measurement method based on disturbances of the uniform magnetic field (e.g. Earth’s magnetic field) is presented. Disturbances are caused by loose material of high magnetic permeability placed in...

The accurate determination of the piston fall rate is one of critical parameters in dead weight testers and piston gauges, as it confirms a quality of machining, instrument accuracy class, and long-term stability. This study introduces a method for determining piston fall rate using two triangulating laser distance sensors. This approach offers ver...

Measurements of mechanical stress dependence of magnetic properties of electrical steels are significant from both theoretical and application points of view. The paper presents a novel measuring setup for testing the magnetoelastic properties of electrical transformer sheets made of grain-oriented and non-grain-oriented steel. The proposed method...

Power conversion devices, such as switching mode power supplies, require the use of a wide range of inductive components. Despite the intense development of advanced magnetic materials for the cores of such elements, SPICE models of these components are still inaccurate and oversimplified. In this paper, a SPICE model of inductive components is use...

Modelling the transient simulation of magnetic circuits is the crucial process for development of modern switching mode power converters. Such models are especially important for newly developed magnetic materials, such as amorphous alloys. Paper presents the gyrator-capacitor model of inductive element with core made of high permeability, Co-based...

The article presents the stress impedance investigation of CoFeNiMoBSi alloy in variation of the applied magnetic field. In order to carry out the study, a specialized stand was developed that allows for loading the sample with stresses and simultaneous action of the DC (direct current) magnetizing field. The tests were carried out for as-cast and...

The results of optimizing the parameters of Co-based ribbons with different chemical composition are presented.The motivation for these studies is the construction of weak magnetic field sensors. The annealed ribbons showlarge impedance changes for saturating external magnetic field, and very large impedance change in the regionof weak field. The h...

The idea, design, and tests of the novel GMI sensor are presented, based on the compensation measurement principle, where the local ‘zero-field’ minimum of the double-peak characteristic was utilized as a sensitive null detector. The compensation field was applied in real-time with the help of microprocessor-based, two-step, quasi-Newtonian optimiz...

This paper presents a process of development, construction, and testing of the system designed to control the thermal relaxation process in liquid metal bath. The task was to use microprocessor-based system to measure and control the heating process in the solder melting pot. This would allow precise control and measurement of temperature in liquid...

The hysteretic GMI effects observed for low values of magnetizing field are presented, on the example of three different cobalt-based amorphous materials. Hysteresis of GMI is a seldom investigated phenomena, but it is very important from the applications point of view. Simplistic test stand capable of automatic GMI measurement series is briefly de...

The significant strain dependence of the hysteretic Giant Magnetoimpedance (GMI) effect in a Co67Fe3Cr3B12Si15 amorphous alloy in a low magnetizing field is presented. A simplistic test stand capable of continuous measurements of GMI characteristics under the influence of strain is detailed. Based on the results, a stress-impedance (SI) sensor is p...

The SI (stress-impedance) effect in amorphous ribbons with varying magnetostriction was investigated. Iron- and cobalt-based ribbons with different magnetostriction coefficients were put under tensile stress in a dead weight tester and the impedance change was investigated in function of applied stresses. Significant differences of characteristics...

In the paper the design and proof-of-concept of compact digital integrator is presented. The proposed Raspberry Pi-based system works as a four-terminal building block for fluxmeters and magnetoelastic transducers. It is meant to replace the currently used RC integrator circuits, and allows for real-time advanced signal analysis practically elimina...

The paper presents the comparative study of Giant Magneto Impedance (GMI) effect in amorphous ribbons of different composition. In paper fundamental aspects of GMI effect, designed measuring stand and obtained results were described. Ribbons with dimension: 1 mm wide, 50 mm long, 22 µm thick in as-cast state, have been investigated with exciting fr...

The paper presents the idea of active LR integrator circuit based on ferrite core. The LR topology, in contrast to contemporary RC, allow for drift-free operation of the integrator. Presented circuit is intended as main component of continuous operation fluxmeters and magnetoelastic transducers, especially working with low frequency signals. Critic...

The following paper presents the idea of distinguishing ferromagnetic objects based on their magnetic signature. This method is based on the measurement of the magnetic moment of the samples. The developed method could be attractive to the industry due to its simplicity, scalability and low implementation costs. The paper presents detailed descript...

The paper presents a device for calibrating microforce sensors. The principle of operation of the calibrator is based on the reversed principle of operation of the current balance – the ampere standard. The design of the device is described in detail. During the implementation of the project, minor corrections were made in project, what has been de...

Current integrator systems usually use active RC integrator circuits. Crucial dificulty associated with this analogue system is the integrator drift. The following paper presents the idea of the active integrator circuit based on inductive and resistive components. This concept allows to eliminate the time drift of the circuit, which is undesired p...

The following paper presents the idea of the active integrator circuit based on inductive and resistance components. Such design allows to eliminate the time drift of the circuit, which is undesired phenomenon resulting from capacitive components utilized in classic constructions. This type of integrator circuit can be used to develop the drift-fre...

The paper presents a test stand that will be used in study of Giant Magneto-Impedance (GMI) effect. Measuring system is based on primary electric law and basic instruments used in electrical metrology. GMI phenomena occurs when a magnetic material is subjected to a DC axial magnetic field and a high frequency AC current. It results in large impedan...

Inductive sensors are widely used to measure rotational speed or wheel's position with the use of triggering circuits known as phase detectors. As the inductive sensor generates differentiated pulses with a steep falling edge it is possible to use standard industrial zero crossing detectors. They produce a digital TTL signal, accepted by digital ci...