microSD Card Research Articles

Multiple channels, low-cost, and dual data storage data logger for building a soil temperature network

Temperature measurement is critical in many areas of research, particularly in agriculture, where it can have a significant impact on crop health and yield. Experiments such as seed germination often require numerous temperature sensors to collect extensive data. Typically, data loggers are used to store information, but market options are expensive and offer limited, non-customizable inputs (channels), creating challenges for comprehensive soil temperature monitoring. This study aims to develop a network of open-source, low-cost data loggers with multiple customizable channels for local and remote temperature data storage. The hardware includes Arduino, temperature sensors, a Real Time Clock, and a LoRa module to transmit data to a LILYGO TTGO board, which sends it to a remote MongoDB database while also storing it locally on a microSD card. In addition, a digital tool was developed to retrieve and display both current and historical readings from the MongoDB database. The total cost of this hardware is approximately US$ 72 (based on current prices) for the simplest network, which is approximately 18 % of the commercial cost. The system achieved a root mean square error (RMSE) of 1.6 °C compared to a manual sampling probe thermometer, proving it to be a reliable measurement source. The hardware developed in this study surpasses commercial options by allowing the integration of multiple sensors and emitters, creating a network of data loggers at a lower cost. In addition to the hardware, an open-source digital tool was developed to visualize historical data at no additional cost.

Smart Internet of Things Power Meter for Industrial and Domestic Applications

Considering the widespread presence of switching devices on the power grid (including renewable energy system inverters), network distortion is more prominent. To maximize network efficiency, our goal is to minimize these distortions. Measuring the voltage and current total harmonic distortion (THD) using power meters and other specific equipment, and assessing power factor and peak currents, represents a crucial step in creating an efficient and stable smart grid. In this paper, we propose a power meter capable for measuring both standard electrical parameters and power quality parameters such as the voltage and current total harmonic distortion factors. The resulting device is compact and DIN-rail-mountable, occupying only three modules in an electrical cabinet. It integrates both wired and wireless communication interfaces and multiple communication protocols, such as Modbus RTU/TCP and MQTT. A microSD card can be used to store the device configuration parameters and to record the measured values in case of network fault events, the device’s continuous operation being ensured by the integrated backup battery in this situations. The device was calibrated and tested against three industrial power meters: Siemens SENTRON PAC4200, Janitza UMG-96RM, and Phoenix Contact EEM-MA400, obtaining an overall average measurement error of only 1.22%.

Connected Robotics for Intelligent Surveillance: An IOT Approach

Abstract: The robot employs the HTTP Communication protocol, enabling users to access live video streaming from the OV2640 camera through a standard web browser. The web interface includes intuitive directional buttons for seamless control, allowing users to command the robot to move left, right, forward, and backward. The locomotion of the robot is achieved through two DC motors integrated with a Robot chassis and an L293D motor driver module. This paper presents the development and implementation of an innovative IoT-based Surveillance Robot designed for remote control, utilizing a Wi-Fi module and a smartphone interface. The portable espionage robot integrates cutting-edge technology, featuring an AI Thinker ESP32-CAM module with an ESP32-S processor, an OV2640 camera, motor drivers, and a robust chassis with two moving wheels. The ESP32-CAM allows the capture and storage of images on a microSD card, facilitating efficient data management. The real-time video feed is transmitted wirelessly to the user's smartphone over a Wi-Fi infrastructure, providing a livestreaming experience. This wireless surveillance robot finds applications in various scenarios such as war fields, disaster management, and beyond, showcasing its versatility in remote monitoring and reconnaissance tasks.

Loopholes in the Indian Banking System concerning Non-Performing Assets (NPAs) – A Case Study of “Axis Bank and HDFC Bank”

This paper presents the development and implementation of an innovative IoT-based Surveillance Robot designed for remote control, utilizing a Wi-Fi module and a smartphone interface. The portable espionage robot integrates cutting-edge technology, featuring an AI Thinker ESP32-CAM module with an ESP32-S processor, an OV2640 camera, motor drivers, and a robust chassis with two moving wheels. The ESP32-CAM allows the capture and storage of images on a microSD card, facilitating efficient data management. The robot employs the HTTP Communication protocol, enabling users to access live video streaming from the OV2640 camera through a standard web browser. The web interface includes intuitive directional buttons for seamless control, allowing users to command the robot to move left, right, forward, and backward. The locomotion of the robot is achieved through two DC motors integrated with a Robot chassis and an L293D motor driver module. The real-time video feed is transmitted wirelessly to the user's smartphone over a Wi-Fi infrastructure, providing a live- streaming experience. This wireless surveillance robot finds applications in various scenarios such as war fields, disaster management, and beyond, showcasing its versatility in remote monitoring and reconnaissance tasks. Keywords: IoT, Surveillance Robot, Wireless Control, ESP32- CAM, HTTP Communication, Video Streaming, Smartphone Control, Disaster Management, Robotics, Remote Monitoring, Reconnaissance.

Development of a GSM-RC Automated Device for Measuring Mobile Communication Signal Strength and Meteorological Parameters

The automated Global System for Mobile Communication Signal Strength and Radio Climatological (GSM-RC) measuring device is an integration of different electronic sensors in a box for an in-situ measuring system. The sensor, data logging, and communication subsystems are integrated for transmitting information on meteorological parameters (MPs) and GSM signal strength level (SSL). The goal is to develop a device that could simultaneously measure MP and SSL of GSM communication systems in any location of interest. This is to reduce significant errors due to a lack of synchronization among multiple devices. To accomplish this objective, we designed an atmospheric sensing system with GSM SSL, temperature, relative humidity, and pressure sensors integrated as a GSM-RC unit. An Arduino microcontroller unit was used to wirelessly transmit the data collected by various sensors in each subsystem and stored on a micro-SD card. A statistical analysis of the SSL between the GSM-RC and the Samsung Galaxy A10s mobile reveals a correlation of roughly 0.99. The ANOVA analysis of variance demonstrates no noticeable distinction between the SSL from developed and conventional devices. The P-value is about 0.93, with α-value of 0.05. The MPs were validated with a standard Vintage Pro weather station, and the data were statistically correlated with accuracies close to unity. A field test was carried out with the device to measure the SSL through the GSM and the selected MP in Akure from January to December 2022. The findings indicate a weak and poor correlation between temperature and signal strength, while relative humidity and pressure have a positive and weak correlations with the signal strength. This implies that an increase in SSL leads to a slight decrease in temperature while the relative humidity and pressure increase slightly. Other than being affordable in terms of production and deployment, the device has also solved the problem of labour-intensiveness arising from bulkiness.

BLYNK RFID and Retinal Lock Access System

The BLYNK RFID AND RETINAL LOCKACCESS SYSTEM describes a digital door lock system that uses an ESP32-CAM module, which is a budget friendly development board with a very small size camera and a micro-SD card slot. The system uses retinal recognition technology to detect the retinal of the person who wants to access the door. The AI-Thinker ESP32-CAM module takes pictures of the person and sends them to the owner via the BLYNK application installed on their mobile phone. The owner can then grant permission to access the door based on the person’s identity. When deploying your BLYNK RFID and retinal scanner project, it's important to consider scalability and maintenance. As your user base and access requirements may change over time, plan for future expansion and updates. Regularly review and update your system's firmware, libraries, and security measures to stay ahead of potential vulnerabilities and evolving best practices in access control. Monitoring and auditing your system's usage is crucial. The Blynk platform can help you gather data on access attempts and system performance, allowing you to analyze the data for any anomalies and potential security breaches. This data can be valuable for compliance, troubleshooting, and performance optimization. Key Word: retinal and RFID scanning for lock to authentic users, using an ESP32-CAM and RFID reader controlling through BLYNK.

Development of Measuring Instrument for the Constructed Wireless Surface and Submarine Vehicle

A measuring instrument designed for use in developed and fabricated Wireless Surface and Submarine Vehicle for water body exploration. These the developed instrument pave way for indigenous research on the oceanography to explored the water body within local environment with less cost. The oceanography measuring instrument developed consists of the following: turbidity, salinity, temperature, pressure, magnetic field sensor, microcontroller, microSD shield, Electrically Erasable PROM (EEPROM), trans-receiver module, and web application alongside with graphical interface. The turbidity and salinity sensor were developed and remain sensors were obtained from the shelf. The turbidity sensor and salinity sensor were design and constructed and respond was very good with MBE of 0.003836 g/l for turbidity and -2.105564 ml/mg for salinity. Also, correlation obtained by the two developed sensors is above 0.9. All the pick from shelf have very good respond. The data was transmitted wireless the obtained were with the on store on EPROM and microSD card when tested with instrument system with Wireless Surface and Submarine Vehicle (WSSV) in dam. Result obtained were strong in agreement and measured correctly. The developed ocean measuring instrument is found to be viable and capable for field deployment.

Smart Surveillance Rover: Real-Time Monitoring with ESP32-CAM and Pan-Tilt Servo Motor Integration

Abstract: This study delves into the development of a robot-guided vehicle using a Wi-Fi module and a mobile phone, with a specific emphasis on creating a discreet device for covert operations, serving as a portable espionage robot equipped with a wireless communication system. The spy robot incorporates crucial components, including a camera, motor drivers, batteries, and two mobile wheels. The implementation involves the AI Thinker ESP32-CAM module, which boasts an ESP32-S processor, OV2640 camera, and a microSD card slot for image storage. Video streaming is facilitated through the HTTP communication protocol, allowing users to access live video feeds from the OV2640 camera via a web browser. The web interface provides intuitive buttons for controlling the car's movements. The robotic car is assembled with two DC motors, a Robot chassis, and an L293D motor driver module, complementing the ESP32-Camera module. Vehicle operation is controlled by signals transmitted from the user's smartphone, while live streaming occurs through the camera mounted on the robot, with the user's smartphone receiving the live streaming data via the Wi-Fi wireless infrastructure.

3D Scanner

Abstract: This research paper presents a revolutionary 3D scanner incorporating an IR Sharp Sensor for capturing objects in all dimensions. The scanner's cutting-edge hardware ensures precise measurements, while the IR Sharp Sensor enables detailed and lifelike 3D model creation. Stored data on a micro-SD card allows easy access on computers, providing user-friendly visualization. Integration with e-commerce websites offers customers a comprehensive view of products through 360-degree viewing, enhancing the online shopping experience. Furthermore, the scanner's capabilities are extended to create virtual environments, enabling immersive experiences and simulations. This research aims to advance 3D scanning technology, merging hardware innovation, software development, and diverse applications

Application note—A novel, low-cost pH-controlled solenoid-based CO2 dosing device for microalgal and cyanobacterial cultivation systems

This application note proposes a novel, low-cost, pH-controlled solenoid-based CO2 dosing device for microalgal and cyanobacterial cultivation systems. The device consists of an Arduino-Uno microcontroller, a (ph-4502c) module, a pH probe, a micro-SD card for data logging, and a relay-controlled solenoid valve. C functions are used to control, and data log the pH and operate the solenoid valve for CO2 dosing in microalgal cultivation systems. With open-source programming, the device can be used for a wide range of applications in both industry and academia. The proposed device is flexible, customizable, and upgradable. This study aims to develop a low-cost pH-controlled, solenoid-based CO2 dosing and data logging device and utilize it for pH control and CO2 dosing in a 200 L outdoor raceway tanks utilized in cultivating and studying the growth of marine cyanobacterium Geitlerinema sp. and Spirulina sp.

Desenvolvimento de um coletor automático de escoamento para estudos com simuladores de chuva

ABSTRACT Soil erosion studies using rainfall simulators are generally expensive and time consuming. Thus, the aim of this study was to develop a prototype of an automatic runoff collector, capable of real-time quantifying runoff volume and soil loss in field trials using a rainfall simulator. The used sensors were chosen based on the type A uncertainty computed from different volumes of water and concentrations of sediment. Through specific programming, the runoff volume, sediment concentrations and the time of occurrence of the collections corresponding to each 200 cm³ of runoff were recorded on a micro-SD card. The robustness of the calibration and the programming developed were also evaluated in the Arduino Mega® 2560 microcontroller. The pressure (PSI.420) and turbidity (ST100) sensors were selected for developing the prototype, which was evaluated in the field with the InfiAsper rainfall simulator. Then, the data collected automatically by the sensors were compared to those obtained by manual measurement. The automatic runoff collector equipped with the PSI.420 and ST100 sensors has potential to obtain and store runoff data, and it was effective in evaluating the erosion process, generating mean errors of 12.25 and 13.16% for runoff volume and soil loss, respectively. The proposed prototype has a low cost of manufacture, in addition to optimizing the collection of erosion data in studies with rainfall simulators.

Robotic-OCT guided inspection and microsurgery of monolithic storage devices

Data recovery from monolithic storage devices (MSDs) is in high demand for legal or business purposes. However, the conventional data recovery methods are destructive, complicated, and time-consuming. We develop a robotic-arm-assisted optical coherence tomography (robotic-OCT) for non-destructive inspection of MSDs, offering ~7 μm lateral resolution, ~4 μm axial resolution and an adjustable field-of-view to accommodate various MSD sizes. Using a continuous scanning strategy, robotic-OCT achieves automated volumetric imaging of a micro-SD card in ~37 seconds, significantly faster than the traditional stop-and-stare scanning that typically takes tens of minutes. We also demonstrate the robotic-OCT-guided laser ablation as a microsurgical tool for targeted area removal with precision of ±10 μm and accuracy of ~50 μm, eliminating the need to remove the entire insulating layer and operator intervention, thus greatly improving the data recovery efficiency. This work has diverse potential applications in digital forensics, failure analysis, materials testing, and quality control.

Recording the Magnetic Field Produced by an Undersea Energy Generating Device: A Low-Cost Alternative

This work describes the characteristics of a device capable of detecting the magnetic field generated by a submerged electrical conductor. This low-cost apparatus is based on the open-source Arduino platform and offers the possibility of monitoring magnetic fields generated by undersea cables. Measuring magnetic fields generated by undersea cables facilitates the development of technologies that will harness marine energy potential. The research is based on published parameters of magnetic field values generated by existing submarine cables. A coil was built to simulate an approximate magnetic field at 10 mT. The magnetic field generated by the coil was used as a reference standard. The device developed has a measurement probe built with an array of SS49E Hall effect sensors placed in a straight line and separated 5 cm from each other. A DS18B20 temperature sensor was added to make the necessary corrections and cancel the influence of temperature during the measurements. A microSD card module was attached to store continuous magnetic field measurements. The device was adjusted under strict laboratory conditions. The functionality of the device developed was confirmed by two samplings in the sea. In these samples, the magnetic field generated by the coil was measured in the entire water column from a depth of 3 m to 150 m. Results indicate that the prototype can successfully perform the necessary functions to quantify the underwater magnetic field accurately with about 10 µT accuracy.

The Open acidification Tank Controller: An open-source device for the control of pH and temperature in ocean acidification experiments

Ocean acidification is the process by which the increase in atmospheric CO2 causes a corresponding increase in seawater CO2 and results in lowering the seawater pH. While this process is likely to have substantial impacts on marine ecosystems, research into the effect of ocean acidification has been limited by the high costs of quality tools to perform ocean acidification treatments in the lab. The Open Acidification Tank Controller is designed to reduce the cost of ocean acidification research by providing a device that can monitor and control pH and temperature of aquaria as well as or better than commercially available research-grade devices, but for less than $250 USD per aquarium. The device is centered around an Arduino Mega 2560 and is assembled into a 3D printed housing. It monitors pH using a BNC glass pH probe and temperature using a three-wire waterproof PT100 temperature sensor. The Open Acidification Tank Controller also features web-based parameter reporting, and data storage to a micro-SD card. This device can hold aquarium pH and temperature at given setpoints, ramp between two values over a user-defined time period, or produce a sine-wave fluctuation in values.

Employing Robotics and Deep Learning in Underground Leak Detection

Leaks in water distribution networks (WDNs) produce significant economic losses. These leaks from underground pipelines affect the surrounding environment in different ways that can be detected using various technologies. This article introduces an unmanned ground vehicle (UGV) equipped with an infrared temperature sensor to remotely detect thermal anomalies on the surface caused by underground leaking pipelines. An MLX90614 low-cost thermopile infrared sensor was proposed to trace the surface temperature above leaking pipelines and record the corresponding position of each reading. Two positioning techniques were tested independently: a satellite navigation system and odometry using a magnetic encoder. Raw data from the temperature sensor along with the corresponding locations were recorded on a MicroSD card using an Arduino Uno Board through analog-to-digital converters (ADCs) and serial peripheral interface (SPI) bus. Experimental work showed the ability of the robot in detecting thermal anomalies caused by leaks accurately with the required trace resolution. Finally, a 2-D convolutional neural network (CNN) solution is introduced for distinguishing true detections from false alarms.

Blockchain and Interplanetary File System (IPFS)-Based Data Storage System for Vehicular Networks with Keyword Search Capability

Closed-circuit television (CCTV) cameras and black boxes are indispensable for road safety and accident management. Visible highway surveillance cameras can promote safe driving habits while discouraging moving violations. According to CCTV laws, footage captured by roadside cameras must be securely stored, and authorized persons can access it. Footages collected by CCTV and Blackbox are usually saved to the camera’s microSD card, the cloud, or hard drives locally but there are concerns about security and data integrity. These issues may be addressed by blockchain technology. The cost of storing data on the blockchain, on the other hand, is prohibitively expensive. We can have decentralized and cost-effective storage with the interplanetary file system (IPFS) project. It is a file-sharing protocol that stores and distributes data in a distributed file system. We propose a decentralized IPFS and blockchain-based application for distributed file storage. It is possible to upload various types of files into our decentralized application (DApp), and hashes of the uploaded files are permanently saved on the Ethereum blockchain with the help of smart contracts. Because it cannot be removed, it is immutable. By clicking on the file description, we can also view the file. DApp also includes a keyword search feature to assist us in quickly locating sensitive information. We used Ethers.js’ smart contract event listener and contract.queryFilter to filter and read data from the blockchain. The smart contract events are then written to a text file for our DApp’s keyword search functionality. Our experiment demonstrates that our DApp is resilient to system failure while preserving the transparency and integrity of data due to the immutability of blockchain.

Internet of Things (IoT) for Soil Moisture Tensiometer Automation

Monitoring of water retention behavior in soils is an essential process to schedule irrigation. To this end, soil moisture tensiometers usually equipped with mechanical manometers provide an easy and cost-effective monitoring of tension in unsaturated soils. Yet, periodic manual monitoring of many devices is a tedious task hindering the full exploitation of soil moisture tensiometers. This research develops and lab validates a low cost IoT soil moisture tensiometer. The IoT-prototype is capable of measuring tension up to -80 Kpa with R2 = 0.99 as compared to the same tensiometer equipped with a mechanical manometer. It uses an ESP32 MCU, BMP180 barometric sensor and an SD card module to upload the measured points to a cloud service platform and establishes an online soil water potential curve. Moreover, it stores the reading on a micro-SD card as txt file. Being relatively cheap (76 USD) the prototype allows for more extensive measurements and, thus, for several potential applications such as soil water matric potential mapping, precision irrigation, and smart irrigation scheduling. In terms of energy, the prototype is totally autonomous, using a 2400 mAh Li-ion battery and a solar panel for charging, knowing that it uses deep sleep feature and sends three data points to the cloud each 6 h.

A versatile and fast-sampling rate wearable analog data logger

We propose a wearable, versatile, and open-source data logger that harvests the capacities of a low-cost microcontroller and enables fast-sampling recording of Analog signals into a microSD card. We describe here the circuit design and an exhaustive list of instructions to build a small, lightweight, and fast sampling rate data logger (up to 5 kHz for simultaneous recording of 3 channels and up to 40 kHz when using a single channel). We provide data analysis instructions, including publicly available scripts to facilitate its replication and customization. As a straightforward proof-of-concept, we tested our device embedded with a three-axial Analog accelerometer and were able to record triple axis acceleration of body movements in high resolution. A Fourier transform followed by a principal component analysis discriminated accurately between body motions of two participants and two types of movement recorded (walking VS running). Our wearable and fast-sampling rate data logger overcomes limits that we identified in previous studies, by being low-cost, capable of fast sampling rate, and easily replicated. Moreover, it can be customized to fit with a wide variety of applications in biomedical research by substituting the three-axial Analog accelerometer with virtually any type of Analog sensors or devices that output Analog signals.•We present a method to build and use a low-cost, fast-sampling rate and wearable Analog data logger, where having an engineering background is not required.•The data logger we present can collect Analog signals from 3 channels simultaneously at 5kHz and up to 40 kHz when using a single channel.•We demonstrate that our data logger can record data from a triple axis Analog accelerometer at 5 kHz, however, signals from virtually any Analog sensor or device that outputs Analog signals can be collected.

A Low-Cost, DIY Ultrasonic Water Level Sensor for Education, Citizen Science, and Research

A low-cost (~$100), do-it-yourself (DIY) ultrasonic water level sensor/datalogger has been designed, constructed, and tested for use in education, citizen/community science, and research settings. The sensor package comprises an ultrasonic distance sensor, a microcontroller running Arduino firmware, a micro-SD card for datalogging, a real-time clock for timekeeping and sleep functions, and an OLED screen for real-time display. Electronics are housed in low-cost custom containers using either upcycled plastic containers or laser-cut acrylic. Reported ultrasonic sensor accuracy is 5 cm across a range of 15–645 cm, with an estimated power budget of 76 days of operation on a rechargeable 10 amp-hr battery. The DIY sensor has been field tested alongside two commercial sensors for 18 days in Wilmington, North Carolina, including during Tropical Storm Colin, with all sensor measurements in close agreement (e.g., root mean squared error of 1.5 cm between the DIY sensor and a proven commercial unit). Potential applications, design and construction, and deployment recommendations for the sensors are described, as well as simple and inexpensive modifications to the sensor and its packaging that could further improve performance. Preliminary lesson plans written to accompany the device for high school- and undergraduate-level educational projects are available.

IoT-Based Smart Wireless Communication System for Electronic Monitoring of Environmental Parameters with a Data-Logger

As the transition toward automated industrial environments gains momentum, the necessity for dependable, real-time environmental monitoring systems becomes increasingly critical. Addressing this urgent need, this paper unveils a sophisticated IoT-based wireless communication system specifically engineered for electronic monitoring of key environmental parameters. An Arduino Nano microcontroller is central to the system’s design, which interfaces with a diverse suite of sensors to monitor temperature, humidity, gas concentrations, and even emergency conditions like fire hazards. Leveraging the capabilities of an nRF24L01 wireless module, the system transmits these multi-faceted sensor readings in real time to a control unit. Once received, the data is vividly displayed on an (organic light emitting diode) OLED screen and logged onto a Micro-SD card for subsequent analysis and historical trend monitoring. Additionally, the system features audio-visual alerts through an electric buzzer and LED, providing instantaneous warnings in critical situations. Notably, the sensor data undergoes rigorous validation by being compared with reference values obtained from NASA’s official databases, ensuring high accuracy and reliability. This comprehensive solution significantly advances industrial safety and efficiency, serving as a robust tool for monitoring and responding to environmental changes in real time.