Journal of Electronics Design and Technology

VLSI-Integrated Energy Harvesting Architectures for Battery-Free IoT Edge Systems

2025-09-25T04:31:54+00:00

The proliferation of the internet of things (IoT) has led to the deployment of billions of interconnected edge devices across diverse domains, including healthcare, agriculture, smart cities, and industrial automation. These devices are required to operate in remote or inaccessible environments, often under strict power constraints. Conventional battery-powered solutions suffer from inherent drawbacks such as limited energy capacity, frequent recharging or replacement requirements, and adverse environmental impact due to large-scale battery disposal. These limitations highlight the urgent need for sustainable and self-sufficient power alternatives.

This research presents a VLSI-based energy-harvesting architecture for self-sustaining IoT edge devices, designed to harvest and efficiently utilize ambient energy sources including solar, radio frequency (RF), thermal gradients, and mechanical vibrations. The proposed system integrates high-efficiency rectifiers, adaptive DC-DC converters, and power management units with an ultra-low-power VLSI processing core operating in sub-threshold regimes. To ensure reliability under intermittent energy supply, the architecture employs non-volatile memory technologies such as FRAM and RRAM, coupled with energy-aware wireless communication modules optimized for low-power data transmission.

Through circuit-level optimization, system modeling, and prototype validation, the design demonstrates continuous operation with minimal external energy support, significantly extending device lifetime compared to conventional battery-dependent nodes. The expected contribution of this work is a scalable, battery-free IoT platform that reduces maintenance costs, enhances environmental sustainability, and accelerates the deployment of truly autonomous edge computing systems.

Development of Patient Mobility Assistance and Transfer System

2025-10-06T11:36:39+00:00

This project introduces a portable and automated patient lifting and transfer system that functions as a mobile seating unit. Unlike conventional wheelchairs, the design features an exoskeleton-inspired structure, enabling patients to sit comfortably in various environments. The primary objective is to improve the quality of life for individuals with paralysis by providing mobility support in both hospital and home settings. The system not only reduces the physical effort required for patient handling but also minimizes workplace strain and injury risks for caregivers. It is adaptable to various body sizes and clothing conditions, enabling safe and convenient patient transfer with minimal human intervention. The device requires only one operator and ensures smooth movement from one location to another with ease.

Kalman Filter-based Sensor Fusion for Enhanced Position Measurement of Autonomous Underwater Vehicles

2025-11-26T05:23:55+00:00

Accurate position measurement remains a critical challenge for autonomous underwater vehicles (AUVs) operating in complex marine environments where GPS signals are unavailable and environmental conditions introduce significant measurement uncertainties. This research presents a comprehensive investigation of Kalman filter-based sensor fusion techniques designed to enhance position estimation accuracy for AUVs through intelligent integration of multiple sensor modalities. The study develops an extended Kalman filter (EKF) framework that synergistically combines data from Doppler velocity logs (DVL), inertial measurement units (IMU), pressure sensors, and acoustic positioning systems to achieve robust and precise localization. Through rigorous mathematical modeling, we derive the state-space representation of AUV dynamics and measurement models, incorporating environmental disturbances and sensor noise characteristics. The proposed fusion architecture implements adaptive noise covariance estimation and outlier rejection mechanisms to maintain filter stability under adverse conditions. Simulation studies conducted across various underwater scenarios demonstrate that the integrated sensor fusion approach achieves position estimation errors below 0.5% of distance travelled, representing a 60–75% improvement over single-sensor dead reckoning methods. The research contributes novel insights into optimal sensor weighting strategies, adaptive filtering techniques for time-varying underwater environments, and practical implementation considerations for real-time AUV navigation systems. Results indicate that the Kalman filter framework successfully mitigates individual sensor limitations while exploiting their complementary characteristics, enabling autonomous underwater missions with extended duration and enhanced operational reliability.

Design of Physics Laboratory: DC Regulated Power Supply Using IC LM723

2025-11-26T05:56:53+00:00

LM723 is a voltage regulator IC that is normally used as a high-precision voltage regulator. LM723 is a monolithic type linear IC available in various packages. In this research, the DC regulated power supply is designed using the IC LM723. This paper presents the design and construction of a dual-regulated ±12V DC power supply that serves two purposes: providing a positive and negative DC output for use in electronic appliances in a Physics laboratory. This power supply gives a precise output voltage using a potentiometer. The circuit diagram was designed with preferred values of components and also used a suitable step-down transformer. In this circuit, a full-wave rectifier to convert AC into DC must be used. The main focus of this paper is to design a dual high-precision power supply used in the physics laboratory.

Simulation of Sinusoidal PWM Waves using MATLAB Simulink Software

2025-12-08T11:33:49+00:00

Pulse width modulation (PWM) is a widely used technique in power electronics to control the output voltage and frequency of inverters. Sinusoidal PWM (SPWM) is a common method in which the switching signals are generated by comparing a sinusoidal reference waveform with a high-frequency triangular carrier. This study presents the simulation of sinusoidal PWM signals using MATLAB/Simulink and SCILAB. The study involves generating the SPWM signals, analyzing their waveform characteristics, and evaluating their effectiveness for controlling inverter output. The simulation results demonstrate the ability of the SPWM technique to produce a high-quality AC waveform with reduced harmonic distortion. Comparative analysis between MATLAB/Simulink and SCILAB tools is also discussed to highlight their suitability for PWM waveform generation and control applications. The findings confirm that both software environments provide effective means for modeling, simulation, and analysis of PWM techniques in power electronic converters.