Experimental Investigation of Effect of Ingredient Particle Size on Dynamic Damping of RTV Silicone Base Magnetorheological Elastomers

AbstractMagnetorheological elastomers (MRE) are a type of smart materials which responds to an externally applied magnetic field which results in enhanced mechanical properties. MRE consists of a non-magnetic matrix material like rubber and a ferromagnetic ingredient. The size of the particle ingredient plays an important role in the property enhancement of the MRE. In the current work, MRE samples were prepared using Room temperature vulcanising Silicone as matrix material and 2 different samples of carbonyl iron powder (3.15μm and 6.25μm diameters) were used as particle ingredients. Microstructure of the sample were studied under Confocal microscope, which showed the smaller diameter powders results in more agglomeration even though the distribution of powders in the matrix were fairly uniform. A test set up was made to conduct dynamic tests to investigate the influence of particle size on the dynamic performance of the prepared MRE samples. Test results in these experiments showed that smaller diameter particle ingredients results in better MR effect

Design and Implementation of Remote Mechatronics Laboratory for e-Learning Using LabVIEW and Smartphone and Cross-platform Communication Toolkit (SCCT)

AbstractThis paper reports a work-in progress at the SOLVE, Students Online Laboratory Through Virtual Instrumentation, at the National Institute of Technology, Surathkal, Karnataka on the design and implementation of a remote lab utilizing emerging technologies.The paper focuses on the basic implementation of a remote laboratory using the publisher-subscriber architecture. Control system and Vibration experiments were chosen for practical implementation which could be monitored and controlled by students using internet. This enabled the remote users to gain a better understanding of the concept of vibrations and control system by performing the real experiment at a time and place of their choice. Both publisher and subscriber were developed using LabVIEW and SCCT add-on for communication. SCCT provides high performance data communication on conventional platforms like LabVIEW, Android, HMTL5, Java, JavaScript, thereby making it multiplatform approach. The method followed for data acquisition by the experimental server, architecture followed at the publisher and subscriber end, brief description about the performable experiments is explained in the present paper

Design and Performance Analysis of a Switched Reluctance Motor Using Finite Element Analysis and Magnetic Equivalent Circuit Model

By being magnet-free, and mechanically robust with a longer constant power range, switched reluctance motor (SRM) is gathering much attention as a potential choice to propel electric vehicles (EVs) and hybrid electric vehicles (HEVs). This paper comprehensively investigates the performance sensitivity to geometric design variables such as rotor diameter, pole arc angles, and yoke thicknesses for an SRM using static two-dimensional (2D) electromagnetic Finite-Element Analysis (FEA). The reason for the change in static characteristics due to variation in reluctance between SRM designs has not been detailed previously. This is addressed by the magnetic equivalent circuit (MEC) model that simplifies the design analysis. Results indicate that stator pole reluctance needs to be given due importance while studying the influence of rotor diameter. Also, it is imperative to set an adequate thickness of the stator and rotor yokes to minimize the effect of saturation on the performance. Rotor diameter and stator pole arc angle have a pronounced influence on the performance while the influence of rotor pole arc angle and yoke thicknesses was relatively less

Comparative Study of Antibacterial Activity between Selected International and Indian Essential Oils against Selected Pathogenic Bacteria

In recent years, the rapid growth in Antimicrobial resistance (AMR) has become a global concern. Essential oils derived from plants that include bioactive components with proven antioxidative and antibacterial activities could be a potential solution to arrest this problem. In this study, antibacterial activities of DoTERRA essential oils such as Onguard, Clove, Teatree, Lavender and Eucalyptus were evaluated with Indian essential oils against clinical pathogenic bacteria. The GC-MS study revealed that cineole, terpinene, eucalyptol, and eugenol were the most prevalent bioactive components in these essential oils. The purity of the essential oils was confirmed with zeta potential and white light absorption spectrophotometer and shows that the Zeta potential of all the essential oils ranges from -51.4 to 0 mV. Using agar well diffusion and Micro broth dilution procedures, the antimicrobial activity of essential oils of clove, lavender, tea tree, eucalyptus, and On-Guard (combined) was assessed against several multi-drug-resistant bacteria. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of essential oils in aqueous and micellar solutions were determined by Micro broth dilution techniques. The most effective antibacterial essential oils were clove, tea tree, and On guard (a blended essential oil with a predominance of Limonene and Eugenol). The current research could result in development of formulas that contain micelle or colloid suspensions of whole essential oils such as clove, On-Guard, or Tea-Tree oil to aid in antimicrobial treatment

Closed Loop Vector Formulation in Eulers Complex Numbers for Multi Loop Planar Mechanisms With N bars A Novel Modeling Approach and Algorithm

This paper presents a novel iterative algorithm incorporated in a user-friendly GUI for modeling the kinematics of multiple looped N-bar closed-loop mechanisms. Past research works have used custom coding or expensive commercial software to analyze the mechanisms of specific applications. The proposed algorithm focuses on kinematics and offers a quick, easy-to-use, cost-effective solution to analyze a wide range of generic mechanisms, reducing the need for custom coding and lowering computational costs. The algorithm employs algebraic equations, such as solving complex closed-loop vector equations using the Euler form of complex numbers, to simulate and derive the unknowns necessary to characterise any generic closed-loop mechanism. The Python code implemented in the algorithm adapts to various scenarios by utilising available information on the position, velocity, and acceleration variables of the mechanisms. The simulation tool can display real-time color contour plots (RGB color scale) for linear and angular velocities and accelerations, simulate mechanisms with multiple loops and switch configurations, and find inverse mechanisms. The approach for solving multiple loop problems and the algorithm utilized to solve the configurations, methods, equations used and GUI features implementation are all described in this study. The case study considered for a four-bar mechanism indicates a strong agreement between the results obtained from the proposed kinematics-based simulator and ANSYS software. These results demonstrate the simulator’s effectiveness in providing low-cost and user-friendly simulation results for various generic mechanisms involving multiple interconnected loops

Comparative assessment of a novel 8/18 multi-teeth with conventional 8/10 in-wheel SRM for an E-Scooter

Electric scooters are increasingly gaining popularity in India owing to rising global crude oil prices and rising levels of vehicular pollution. Most of them are currently powered by expensive in-wheel (IW) permanent magnet (PM) brushless DC motors. Owing to their simplicity, and ruggedness while being cost-effective (since they do not employ PMs), switched reluctance motors (SRMs) are a viable alternative. Despite these benefits, SRMs possess drawbacks such as low torque density and inferior efficiency. Recently, a multi-teeth (MT) SRM with an improved performance was reported. However, the design of MTSRM topologies and their electromagnetic performance have not been explored sufficiently. In this paper, a design formula governing the selection of the number of MT and rotor poles for MTSRMs has been proposed. Using this, a novel four-phase 8/18 IW-MTSRM is derived and proposed for an E-scooter. The characteristics of the proposed SRM are numerically compared with a conventional 8/10 SRM based on magnetic characteristics, efficiencies and steady-state operation for the complete torque-speed range. Results indicate that the proposed 8/18 MTSRM has a higher peak torque capacity, torque density, superior drive cycle efficiency and reduced torque ripple. Further, the FEA model is validated experimentally on a downsized 8/18 MTSRM prototype