An Approach of Fuzzy Logic H∞ Filter in Mobile Robot Navigation Considering Non-Gaussian Noise

This chapter has presented an analysis of H∞ filter‐based mobile robot navigation with fuzzy logic to tolerate in non‐Gaussian noise conditions. The technique exploits the information obtained through H∞ filter measurement innovation to reduce the noises or the uncertainties during mobile robot observations. The simulation results depicted that the proposed technique has improved the mobile robot estimation as well as any landmark being observed. Different aspects such as γ values, noise parameters, intermittent measurement data lost and finite escape time issues are also analysed to investigate their effects in estimation. Different fuzzy logic design configurations were also studied to achieve better estimation results. As demonstrated in this work, fuzzy logic offers reliable estimation results compared to the conventional technique

Synthesis, characterisation and evaluation on the performance of ferrofluid for microplastic removal from synthetic and actual wastewater

Synthesis of ferrofluid without the addition of stabilizing agents or surfactants is an innovation of new method for microplastic removal. This study focuses on the ability of several types of oils as carriers and how they may improve the removal efficiency of the microplastic. The method is relatively low cost, simple and sustainable. The formation of ferrofluid involved the mixing of oil and iron oxide powder. The experimental work was commenced by adding 2 mm polyethylene terephthalate (PET) microplastics into synthetic ferrofluid. Then, the removal efficiency of microplastics was examined by varying the elements of ferrofluid based on three specific parameters, namely type of oil, volume of oil and dosage of iron oxide to obtain a standard formulation of the optimum results. Overall findings of the study indicated that the optimum formulation for ferrofluid preparation was at a ratio of 1:2.5 (volume of oil: dosage of magnetite) using lubricating oil which has successfully removed 99% of microplastic from water media. Subsequently, the physical and chemical properties of the prepared ferrofluid were also analysed using scanning electron microscope (SEM) and Fourier transform infrared (FTIR) spectroscopy. Performance evaluation of the prepared ferrofluid on actual wastewater (laundry wastewater) revealed that 64% of microplastics were removed after treatment

Oxidation of p-Cresol by ozonation

Oxidation of p-Cresol was investigated by using ozonation process. The aim of this research is to assess the effectiveness of ozonation on oxidation of micropollutant such as p-Cresol. Ozonation performance was evaluated based on p-Cresol concentration reduction and chemical oxidation demand (COD) reduction. It was found ozonation at pH11 achieved the highest p-Cresol degradation, with 95.8% of p-Cresol reduced and 96.0% of COD reduced, for an initial 50 mgL-1 of p-Cresol. The degradation of p-Cresol could be expressed by second-order of kinetic model. The second-order rate constant k increases as the initial pH increased, but decreases with the increasing of initial p-Cresol concentrations. Besides, the absorption spectra of p-Cresol over ozonation time were analyzed by spectrophotometry. The evolution of absorption spectra of p-Cresol degradation suggests that the oxidation of p-Cresol follows three stages mechanisms with cycloaddition as the first step to produce aromatic intermediates followed by ring-opening reactions, degradation of the intermediates, and subsequently achieved mineralization

Investigation on AC breakdown of vegetable oils with insulated electrodes

Most of power transformer design today is still using oil filled type which laminated iron core with paper insulated copper conductors. Oil is an important part in power transformers as electrical insulation, information carrier and cooling medium. Besides oil, paper insulation also plays important role as dielectric material of transformer. The influence of oil especially vegetable-based oil and paper insulation on the dielectric strength of transformer oil has attracted many researchers to do investigation. This paper presents a study of the quasi-uniform field AC breakdown voltages under bare electrodes, paper insulation for barrier and covered electrodes (to replicate the transformer windings) of Palm Oil (PO), Coconut Oil (CO) and Mineral Oil (MO). The data obtained from all tests were analyzed using Gaussian and Weibull distribution to determine the withstand voltages for each type of oils. The experiments were using test cell as specified by IEC 156 with 2.5 mm gap distance under uniform field

Syngas production from glycerol dry reforming using Nd2RuO5 perovskite catalysts

Currently, fossil fuels as the global energy sources have become a liability due to the emission of greenhouse gases that causes global temperature elevated and climate changes to happen more frequently. As a result, glycerol dry reforming (GDR) has been a research priority, owing to its reforming capabilities in turning greenhouse gases (CO2) and biodiesel byproducts (glycerol) into syngas. The choice of catalysts is critical for increasing the efficiency of the syngas production process. Hence, this paper studies the application of Nd2RuO5 perovskite catalysts on the dry reforming of glycerol. Before characterization, the catalysts were prepared by using the Pechini Sol-Gel method. GDR reactions were conducted using a fixed-bed reactor at operating conditions; 873 – 1173 K and CO2 to Glycerol ratio (CGR) at 1:1. Based on XRD finding, the dominant phase belongs to Nd2RuO5, a pseudo double perovskite. The reduction profile from TPR showed a lowered reduction temperature which belongs to Ru that reduced into Ru0. The images of perovskite showed a well dispersed and smooth surface, and no agglomeration occurred on the pore sites. From the catalytic evaluation on the effect of temperature, the best temperature was observed at 1073 K, giving the highest glycerol conversion at 69%, whereas for H2, CO yields 20.8% and 13.8%, respectively. Intense carbon formation has been detected at post XRD analysis which later confirmed to be a filamentous type, that oxidized at low oxidation temperature from 400 – 500 K

FEKF Estimation for Mobile Robot Localization and Mapping Considering Noise Divergence

This paper proposed an approach of Fuzzy-Extended Kalman Filter(FEKF) for mobile robot localization and mapping under unknown noise characteristics. The technique apply the information extracted from EKF measurement innovation to derive the best estimation output for a mobile robot during its observations. These information is then fuzzified using Fuzzy Logic technique with very few design rules to control the information which at the end further reducing the error about the measurement and consequently provide better localization and mapping. Simulation results are also presented to describe the efficiency of the proposed method in comparison with the normal EKF estimation that emphasize FEKF exceeds the estimation results of normal EKF in non-Gaussian noise environment

Analysis of Intermittent Measurement for KF-based SLAM

This paper investigates the impact of intermittent measurement to the Simultaneous Localization and Mapping (SLAM) of a mobile robot. Intermittent measurement is a condition when the mobile robot lost its measurement data during observations due to sensor failure or imperfection of the system. SLAM is an estimation process that requires measurement data recursively for data update. The analysis focused on the effect of intermittent measurement on the position estimation and state error covariance during intermittent and after intermittent occurred. From the analysis, it can be concluded that intermittent measurement may lead to incorrect estimation of robot pose and its error covariance

FEKF ESTIMATION FOR MOBILE ROBOT LOCALIZATION AND MAPPING CONSIDERING NOISE DIVERGENCE

ABSTRACT This paper proposed an approach of Fuzzy-Extended Kalman Filter (FEKF) for mobile robot localization and mapping considering unknown noise characteristics. The techniques apply the information extracted from EKF measurement innovation to derive the best output for mobile robot estimation during its observations. This information is then fuzzified using Fuzzy Logic technique, designed with very few design rules to control the information. The method can further reduced measurement error and as a result provides better localization and mapping. Simulation results are also presented to describe the efficiency of the proposed method in comparison with the normal EKF estimation. Preliminary results emphasize that FEKF has exceeds the estimation results performance of normal EKF in non-Gaussian noise environment

Analyzing the Mobile Robot Localization Performance in Partially Observable Conditions

This paper deals with theoretical investigation of robot localization considering partial observability conditions. The problem is very important as most of the mobile robot applications are controllable but not observable due to some aspects. The paper investigate the importance of correlation to the mobile robot estimation through the technique of decorrelating some of the elements of state covariance of the updated state covariance. To demonstrate the effect of correlation, two cases of partial observability are examined which are the unstable and stable partial observability. The cases are build based on the configurations of the state covariance for mobile robot references when doing observations. Our preliminary results suggest that the system with stable partial observability shows very good and consistent estimation while the unstable case lead to inconsistency and erroneous estimation

Robotics in school: a stem approach for creativity and innovation

Nowadays, knowledge in the field of Science, Technology, Engineering and Mathematics (STEM) is becoming very important. In order to attract students’ interest in this field, robotics lesson by using LEGO MINDSTORM EV3 is introduced to schools around Pekan, Pahang in collaboration with Pejabat Pendidikan Pekan, Pahang. This lesson is not only focussing on learning, it also shows how to design and assemble a machine or a robot. Besides the project is able to motivate students to think creatively and innovatively when doing activities. A lot of programmes and activities have been organised such as workshop, class and exhibition to deliver the lesson. This entire programme helps students and teachers to assess their skills and knowledge in science and mathematics. These programs have indirectly increases the interest among students and teachers as well as improving their academic performances. Our preliminary analysis shows that a number of students participated in this program have gained good academic results especially in Science and Mathematics. Undeniably, this program is able to support Science, Technology, Engineering and Mathematics (STEM) program especially for students and teachers in Pekan, Pahang