Sensors and Digital Signal Conditioning in Mechatronic Systems

Essential part of a mechatronics system is the measurement system that senses the variations in the physical parameters, such as temperature, pressure, displacement, and so on, and converts it to voltage or current. The control of industrial processes and automated manufacturing systems requests accurate, moreover, linearized sensor measurements, where numerous sensors have nonlinear characteristics. In mechatronic systems, accurate measurement of the dynamic variables plays a vital role for the actuators to function properly. This chapter presents linearization methods and a measurement system in mechatronics consisting of temperature sensors and the signal-conditioning circuits, providing detailed information on design process of an embedded measurement and linearization system. This system uses a 32-bit microcontroller for thermocouple (T/C) cold junction compensation, amplification of low output voltage, then conversion to digital, and linearization of the type K thermocouple’s output by software to output a desired signal. Piecewise and polynomial methods are used in linearization software, and the implemented embedded system for the linearization of a type K T/C is presented as a case study. The obtained results are compared to give an insight to the researchers who work on measurement systems in mechatronics

Embedded Controller Design for Mechatronics System

Many mechatronic systems have challenging control difficulties due to the high nonlinear structures and time‐varying dynamic behaviors. In addition to these, there are external disturbances, which cannot be predicted and change according to uncontrolled working environments. Conventional controllers are insufficient to solve the aforementioned problems and to compensate the environmental disturbances. Therefore, adaptive controllers have been proposed as a solution to these inefficiencies of conventional controllers. Adaptive control is applied for solving the control problem of the mechatronic sun tracker that ensures the movement of the mechanism to harvest maximum energy coming from solar to the PV module surface during the sunshine duration. For this type of control problems, conventional controllers are very limited and they have a lot of deficiencies. The adaptive mechanism governed by an adaptation law is the heart of any adaptive controller. We establish the adaptation law for the plant control system using Lyapunov stability theory. This adaptation law is precise for a generic second‐order system; hence, it is obviously applicable for adaptive control of other second‐order systems in different realms, such as industrial production system, military, and robotics

Dolmabahçe'de tarih talanı

Taha Toros Arşivi, Dosya No: 41-Beşiktaşİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033

Design of a Plant Leaf Area Meter Using PV Cell and Embedded Microcontroller

WOS: 000328397400001This paper presents the development of a solar cell based simple and practical leaf area meter. The system has a silicon solar module which is composed of 6 series connected cells, a light source, and a parabolic reflector with opal glass for diffusing the light. Partial shading effect on PV cell's voltage and current are evaluated with different geometrical shapes for testing the performance of the model, and the resulting equations for voltage and current changes with respect to measured areas are obtained. The measured current has a good correlation: R-2 > 0.99 for regularly shaped leaves and R-2 > 0.95 for irregularly shaped ones. The resulting voltage and current measurements are then fed to an ARM Cortex M3 core 32-bit LM3S1968 microcontroller via a voltage and current measuring unit. The calculated leaf areas from the obtained area-current relations are shown on an OLED graphics display. The whole system is easy to use and user-friendly. The leaf area measurements are confirmed by comparing the results with measurements of grid counting method

INVESTIGATION OF THE EFFECTS OF WALNUT BIODIESEL ON A DIESEL ENGINE EXHAUST EMISSIONS

Diesel engines are the most efficient thermal machines capable of reaching up to approximately 40% of thermal efficiency. Different studies are carried out to increase the efficiency of diesel engines and also to reduce environmental pollution. The studies aimed at improving the combustion process constitute the most important part of them. As is known, with the improvement of combustion process; Besides increasing the efficiency of the engine, environmental pollution is also reduced. For this reason, in recent years to improve combustion process in diesel engines; Both structural (conconstructive) studies and fuel-related studies are underway. Structural works include exhaust manifold designs, improving the shape of the combustion chamber, increasing the valve count and Valve section area, regulations and improvements in the spraying system, the expansion of the turbocharger application, etc. Located. In the studies related to fuels; More economical use of existing fuels and studies on different alternative fuels can be given as examples.In this study, Biodiesel was produced from walnut oil by transesterification method. The walnut biodiesel is then mixed with the Eurodiesel fuel, which will be 7% (B7) and 10% (B10) by volume. Eurodiesel fuel was accepted as comparison fuel. Diesel engines with common-rail fuel system were used in the experiments. The results of the tests were compared with the emission values of CO, CO2, HC, O2, smoke and NOx with Eurodiesel fuel values

Displacement of the Buildings According to Site-Specific Earthquake Spectra

The probabilistic seismic hazard curves were based on appropriate attenuation relationships at rock sites with a probability of exceedance of 10% in 50 years in this study. Results from the model were compared to the response spectra proposed in Section 7 of TEC ‘07 and were found to dier in both amplitude and frequency content. The impact of these dierences has been investigated with respect to building performance evaluation. Specifically, modal capacity diagrams and response spectra have been obtained for five buildings. Based on the diagrams and spectra, peak displacements have been calculated as well, revealing significant dierences in the demand displacement curves of the buildings. As a result, damage estimates and predicted building performance will deviate from site specific performance to a greater degree. Using site-specific spectra and field data will be important for future earthquake-resistant design. One of the conclusions of the study is that the Code spectra do not oer a sucient or comprehensive enough set of seismic demands and would lead to an under estimation of seismic hazard in the region of study. Therefore, site-specific design spectra for the region should be developed which reflect the characteristics of local sites

The relationship between anxiety, coping strategies and characteristics of patients with diabetes

Background This study provided essential information, about Turkish patients with type I and type II diabetes, concerning: levels of anxiety, coping strategies used, and relationships that exist among anxiety, coping strategies, sociodemographic and medical characteristics. Methods A sample comprising 161 Turkish adults with both types of diabetes participated in the study. The trait anxiety scale, the brief COPE, sociodemographic and medical questionnaire were administered to patients with diabetes. Results The mean age was 49.01 (SD = 9.74), with a range from 20 to 60 years. The majority of the participants were female (60.9%) and type II diabetes (75.8%). 79% of the participants experienced anxiety. A clear majority of the participants reported to integrate their diabetes. Acceptance, religion, planning, positive reframing, instrumental support, emotional support, self-distraction and venting were the most frequently used coping strategies. The most frequently used problem-focused and the emotion-focused coping strategies were found to be similar in both type I and type II diabetes. However, participants with type II diabetes had relatively higher scores on the problem-focused strategies than those with type I. Participants with type I diabetes used humour, venting and self-blame more than those with type II diabetes. Other findings indicated that only a small minority responded to diabetes-related problems by denial, behavioural disengagement and substance use. Significant correlations were found among anxiety, coping strategies and sociodemographic characteristics of the participants. Moreover, Self-blame was found to be correlated significantly with both the problem-focused and emotion-focused coping strategies. Self-blame was also significantly correlated with both instrumental support and emotional support indicated that higher self-blame caused more frequent use of instrumental and emotional support by patients with diabetes. Conclusion The findings of this study indicate that care for patients with diabetes should address their physical, psychological, social and economic wellbeing and the findings point to the importance of taking individual coping strategies into account when evaluating the impact of diabetes on psychosocial wellbeing. Because of the mean of anxiety were not in normal range, for this study, health professionals need to pay attention to patient's psychological state. This is especially true for patients who are likely to use self-blame and behavioural disengagement as a coping strategy. Through psychosocial interventions, professionals need to assist patients in establishing positive self evaluations. Delineation of coping strategies might be useful for identifying patients in need of particular counselling and support

Komşu Ülkelerle Yapılan Dış Ticaretin DYY Girişleri Üzerine Etkisi: Gelişmekte Olan Ülkeler İçin Panel Veri Analiz

Doğrudan yabancı yatırım (DYY) kararları açısından, hedef ülkenin teknolojik yeterliliği, üretim verimliliği, maliyet avantajları yanında dışa açıklığı da oldukça önemlidir. 1990’lı yılların başında yoğunlaşan liberalleşme politikaları gelişmekte olan ülkelere yönelik DYY akımlarını arttırmıştır. Bu çalışmada, Gelişmekte olan ülkelerin komşularıyla olan ticari ilişkileri ölçüsünde sundukları geniş piyasa hacmi avantajı ve ham madde ve yarı mamul tedariki avantajının DYY girişlerine etkisi araştırılmıştır. Yapılan analizler sonrasında, 94 gelişmekte olan ülkenin ele alındığı veri seti için sabit etkiler modelinin uygun olduğu bulunmuştur. Modelimizin varsayımları sağlayıp sağlamadığı test edilmi ve varsayımlardan sapmalara karşı geliştirilen Parks- Kmenta (GEKK), Beck-Katz (PCSEs) ve Driscoll-Kraay dirençli standart tahmincileriyle tahmin edilmiştir. Analiz sonucunda, komşu ülkeler ile yapılan ticaretin DYY girişleri üzerinde olumlu etkisi olduğu bulunmuştur

Single- and multi-layer arsenene as an anode material for Li, Na, and K-ion battery applications

Revealing ideal electrode materials with required functionalities is a crucial step to develop high-performance alkali-ion batteries. In this study, we investigate the potential of single- (SL) and multi-layer (ML) arsenene phases (buckled and symmetric washboard) to be used as an anode material by means of abinitio calculations. The interaction of alkali metal atoms (M: Li, Na, and K) with arsenene is examined to reveal strong adatom-electrode binding and low diffusion barriers. Provided that the initial crystalline patterns are maintained, the possible M orderings (MxAs) are investigated for varying ion concentrations (x). The structural deformations and the decrease in formation energy with increasing x indicate probable structural transformations. The abinitio molecular dynamics simulations confirm that the ordered patterns are prone to instability and crystalline to amorphous transition is induced at ambient temperature. The calculated (average) open-circuit voltages are between 0.65–0.98 V with the specific capacity range of 358–715 mAhg−1 for SL- and ML-MxAs. Strong metal-electrode interaction, fast diffusion, and desired voltage range suggest arsenene as a promising anode material for alkali-ion batteries to be utilized in low charging voltage applications. © 2020 Elsevier B.V