Browsing by Author "Mohith, M."

Filter results by typing the first few letters
Now showing 1 - 5 of 5
  • No Thumbnail Available
    Item
    Analysis of annularly excited bossed diaphragm for performance enhancement of mechanical micropump
    (Elsevier B.V., 2022) Mohith, M.; Karanth P, N.K.; Kulkarni, S.M.
    Piezo actuated mechanical micropumps find extensive application in microfluidic devices for precise delivery of the fluids. The deflection of the diaphragm dramatically influences the performance of the mechanical micropump. The present work emphasises a novel method of annular excitation of the diaphragm to enhance the volumetric performance of the micropump. The proposed work incorporates a bossed diaphragm excited through a novel approach of annular excitation. The amplified piezoelectric actuator is used as a primary source of actuation. In the present work, theoretical and finite element methods are considered to analyse the deflection behaviour of the bossed diaphragm under central and annular excitation. Experimental characterisation is carried out to validate the results obtained from finite element analysis. The annular excitation of the bossed diaphragm delivers a higher range of deflection when compared with the conventional central excitation. The maximum simulated deflection of about 1998.4 µm is achieved with an annularly excited bossed diaphragm at 150 V, 45.5 Hz, which is far superior to the deflection range achieved with a conventional centrally excited bossed diaphragm with the deflection of 725.91 µm at 150 V, 9.96 Hz. The corresponding experimental deflection of annularly excited and centrally excited bossed diaphragm is about 1953.4 ± 8.00 µm at 50 V, 43.5 Hz and 717.99 ± 4.00 µm at 150 V, 9.5 Hz. © 2022 Elsevier B.V.
  • No Thumbnail Available
    Item
    Application of Modeling and Control Approaches of Piezoelectric Actuators: A Review
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023) Kanchan, M.; Mohith, M.; Bhat, R.; Naik, N.
    Piezoelectric actuators find extensive application in delivering precision motion in the micrometer to nanometer range. The advantages of a broader range of motion, rapid response, higher stiffness, and large actuation force from piezoelectric actuators make them suitable for precision positioning applications. However, the inherent nonlinearity in the piezoelectric actuators under dynamic working conditions severely affects the accuracy of the generated motion. The nonlinearity in the piezoelectric actuators arises from hysteresis, creep, and vibration, which affect the performance of the piezoelectric actuator. Thus, there is a need for appropriate modeling and control approaches for piezoelectric actuators, which can model the nonlinearity phenomenon and provide adequate compensation to achieve higher motion accuracy. The present review covers different methods adopted for overcoming the nonlinearity issues in piezoelectric actuators. This review highlights the charge-based and voltage-based control methods that drive the piezoelectric actuators. The survey also includes different modeling approaches for the creep and hysteresis phenomenon of the piezoelectric actuators. In addition, the present review also highlights different control strategies and their applications in various types of piezoelectric actuators. An attempt is also made to compare the piezoelectric actuator’s different modeling and control approaches and highlight prospects. © 2023 by the authors. Licensee MDPI, Basel, Switzerland.
  • No Thumbnail Available
    Item
    Bond Graph Modeling and Simulation of Hybrid Piezo-Flexural-Hydraulic Actuator
    (Multidisciplinary Digital Publishing Institute (MDPI), 2023) Rudraksha, R.; Mohith, M.; Kanchan, M.; Powar, O.S.
    In this study, a hybrid piezo-flexural-hydraulic actuator is modeled and simulated using bond graph methodology. The hybrid actuator comprises piezoelectric stack actuator, mechanical flexural amplifier, and hydraulic piston actuator. The piezoelectric stack actuator produces electrically controllable displacement. This displacement is amplified by a cascading combination of flexural amplifier and hydraulic actuator. A domain-independent bond graph model for the proposed hybrid actuator is developed. Using this bond graph, a mathematical model and a state space representation for the hybrid actuator are derived. The bond graph model is simulated using a 20-sim bond graph simulation software. The results of the simulation provide displacement characteristics and sensitivity analysis for each component and the hybrid actuator as a whole. The study plays a significant role in understanding the dynamic behavior of a multi-domain system using the bond graph methodology. © 2024 by the authors. Licensee MDPI, Basel, Switzerland.
  • No Thumbnail Available
    Item
    Performance analysis of a novel piezo actuated valveless micropump for biomedical application
    (American Institute of Physics Inc. subs@aip.org, 2020) Mohith, M.; Upadhya, A.R.; Karanth P, N.K.; Kulkarni, S.M.
    Micropumps constitute an integral part of microfluidic systems for delivery and control of a precise volume of fluids in a specific direction. Micropumps find extensive utilization in biomedical applications such as drug delivery, biological fluid transmission, organic analysis, and other applications such as electronic cooling, chemical analysis, spacecraft, etc. In the present work, design, fabrication, and testing of a novel valveless micropump with amplified piezo actuator have been presented explicitly for biomedical fluid transmission. In the current work, design, manufacturing, and experimental study of a novel micropump with amplified piezo actuator have been presented explicitly for biomedical fluid transmission. The designed prototype of the micropump has a distinctive feature of the disposable chamber, which allows the pump chamber to be disposed off upon use, thus overcoming the problem of contamination. The micropump employed low-cost polymethylmethacrylate (PMMA) as the structural material with silicone rubber diaphragm. The proposed prototype of the micropump was capable of delivering 5.771 ml/min of water for a sinusoidal input voltage of 150 V at 5 Hz. © 2020 Author(s).
  • No Thumbnail Available
    Item
    Performance analysis of valveless micropump with disposable chamber actuated through Amplified Piezo Actuator (APA) for biomedical application
    (Elsevier Ltd, 2020) Mohith, M.; Karanth P, N.; Kulkarni, S.M.
    The precise manipulation of fluid through pumping systems has been the technological challenge in microfluidic applications. The biomedical applications call for precise and accurate delivery of fluid through miniaturized pumping systems. This paper presents a novel valveless micropump for biomedical applications operated by the Amplified Piezo Actuator. Integrating the disposable chamber and reusable actuator with the proposed micropump allows the actuator to be reused and eliminates the possibility of infection or contagion. The micropump was fabricated using low-cost polymeric materials like Polymethylmethacrylate (PMMA), Silicone rubber through CNC milling, Laser Cutting, conventional moulding operation. The micropump chamber, nozzle/diffusers, and a bossed diaphragm constituted disposable part and Amplified Piezo Actuator with structural support formed the reusable part of the micropump. The bossed diaphragm of the pump chamber consists of a central cylindrical protrusion to reduce the force of adhesion on the diaphragm and transmit force required for micropump actuation. A theoretical analysis was performed to assess the effect of diaphragm thickness and the bossed region on the effective stiffness of the diaphragm, which in turn influences the deflection achieved. Besides, an analytical approach has been presented to address the effect of adhesive force on the diaphragm surface due to the residual fluid and chamber depth. The experimental characterization of the micropump was carried out to determine the optimal performance parameters with water, fluids mimicking blood plasma, and whole blood. Based on the experimental results, the pumping rate and head developed by the micropump have been significantly affected by factors such as bossed ratio, diaphragm thickness, depth of the micropump chamber, and viscosity of the fluid. The optimum configuration of the micropump cosidered silicone rubber diaphragm with thickness of 0.20 mm having a bossed ratio of 0.33 and a chamber depth of 1.25 mm. With the optimal operating parameters of 150 V sinusoidal input of frequency 5 Hz, the proposed micropump was capable of delivering 7.192 ml/min, 6.108 ml/min, and 5.013 ml/min of water and blood plasma, whole blood mimicking fluid with the maximum backpressure of 294.00 Pa, 226.243 Pa, and 204.048 Pa respectively. The corresponding resolution, i.e., pumping volume/stroke of the micropump was about 23.972 µl, 20.358 µl, and 16.708 µl, respectively. © 2020 Elsevier Ltd