GSM Based Smart Electronics Nose for Onion Preservation: A Sustainable Solution for Agriculture

Gawade SS, Shedge DN, Deshpande JD, Pawar AM and Patil SN

Published on: 2025-07-22

Abstract

The conservation of agricultural products, particularly perishable items like onions, wheat, rice, potatoes, maize, etc., is a critical aspect of ensuring food security and minimizing post-harvest losses. On inspection of farmers, end users face a number of challenges in traditional preservation methods; this study proposes an innovative electronic system particularly for onion preservation. The envisioned electronic system leverages advanced technologies, including sensors and control mechanisms, to create an efficient and automated onion storage environment. The parameters such as humidity, temperature, methane, ethylene, carbon monoxide, and airflow within the storage facility are monitored and controlled in real-time to optimize conditions for onion preservation. The embedded system is designed to adapt to varying environmental factors and maintain an ideal storage environment throughout the storage period. Additionally, the electronic system incorporates smart features, allowing remote monitoring and control via GSM or the Internet of Things (IoT) technology. This facilitates accessibility for farmers and stakeholders, enabling them to oversee onion storage conditions from anywhere, thereby enhancing convenience and efficiency. The proposed onion preservation electronic system aims to extend the shelf life of onions, reduce post-harvest losses, and contribute to sustainable agriculture practices. The integration of cutting-edge technology into onion storage processes holds promise for improving overall food supply chain resilience and meeting the growing demands of a global population. Therefore, an Arduino-based smart electronics system design for early onion spoil detection and the details regarding the design and results are interpreted in this paper.

Keywords

Internet of things; GSM; Temperature; Humidity; Methane; Ethylene; Electronic nose; Embedded system

Introduction

The advances in electronics technology today allow us to build small, inexpensive, and battery-powered sensing devices with onboard processing and communication capabilities, called wireless sensing devices. The devices are such as Internet of Things (IoT), Wireless Sensor Node (WSN), GSM, Bluetooth, or Wi-Fi based [1]. Typically WSN and IoT GSM-based systems are considered for many control applications at the sensing level, leaving the control and actuation planes for other systems to perform. Wireless Sensor Networks (WSNs) have gained worldwide attention in recent years, particularly with the proliferation of Micro-Electro-Mechanical Systems (MEMS) technology, which has facilitated the development of smart sensor nodes. A wireless sensor network is a collection of sensor nodes organized into a cooperative network. Each Smart Sensor node consists of processing capability (one or more microcontrollers, CPUs, or DSP chips), may contain multiple types of memory (program, data, and flash memories), has an RF transceiver (usually with a single omnidirectional antenna), has a power source (e.g., batteries and solar cells), and is a low-power device equipped with one or more sensors. A variety of mechanical, biological, chemical, optical & magnetic sensors may be attached to the sensor node. Since the sensor nodes have limited memory and are typically deployed in difficult-to-access locations, a radio is implemented for wireless communication to transfer the dataset to the base station. The nodes communicate wirelessly and often self-organize after being deployed in a particular network system. WSNs have great potential for many applications in fields such as military target tracking and surveillance. Natural disaster relief, biomedical health monitoring, hazardous environment exploration, seismic sensing & agriculture [2]. Among these various fields, agriculture application is considered one of the most promising services for wireless sensor network realization to enhance food-crop production and reduce the burden on farmers.

Recently, WSNs, IoT, and GSM-based wireless sensor network technology have become the most popular technology for monitoring and controlling agricultural parameters. In general, most crops are very susceptible to weather conditions such as temperature, humidity, intensity of illumination, etc. [3-5]. This is a significant burden for farmers to observe weather conditions for every hour and for every day. The occurrence of fire is also the most fatal of agricultural disasters. These facts imply that the agricultural sector needs sophisticated embedded systems for real-time monitoring services of whole environmental conditions for improving crop production, plant growth, and seed storage and preventing sermons and preventing them from serious disasters. There is a matter of energy efficiency as one of the fundamental problems in WSN, and consequently special challenges for energy-efficient data processing and communication must be addressed.

An embedded system is a special-purpose electronic system designed to perform a dedicated application, often with real-time constraints [6-8]. Therefore, deploying embedded technologies, the GSM-based smart electronic nose is designed for early detection of food grain storage conditions in warehouses and increases the quality and life of food grains and reduces the burden on farmers. The GSM is mostly suitable in the present application because using the GSM sends the message to the storage owner, farmer, or relevant person and updates the status form the remote side. In the present paper, a system is reported for onion parameter preservation. The biggest advantage as compared to WSN is it reduces the number of nodes for communicating remote locations to the coordinator. IoT is also applicable to this application for broadcasting the data on the internet anywhere from a remote location [9-12].

The sensor produces the voltage proportional to the physical parameter. This voltage is fed to the microcontroller (Arduino) after amplification. The Arduino is programmed such that it converts the analog input voltage into digital using the internal on-chip ADC. This digital data is calibrated and displayed on the LCD, which is connected to port B of the microcontroller as well as the serial terminal of the PC. At the same time, the calibrated data is transmitted serially through the Tx pin through GSM. The GSM module sends the message to the stored number.

Designing Of GSM Based Smart Node For Onion Preservation

Deploying embedded philosophy, a system is designed about the advanced microcontroller, the Arduino ATmega328 GSM module, and the details of this design are described. The hardware of the typical sensor node, at a glance, is depicted in Figure 1 in terms of a block diagram.

Figure 1: Block Diagram for GSM Based Smart Real Time System.

It is designed to detect and compute the values of the physical parameters in engineering units. It comprises smart sensors, a signal conditioner, a data acquisition system, the microcontroller, a display unit, and a power supply section. Moreover, to ensure the wireless communication, the GSM module is employed. The system is designed to monitor the humidity, temperature, and concentration of gases in a warehouse environment [13-16].

DHT11

Humidity and temperature areimportant parameters in any storage application. For good quality, extending the shelf life of onions and reducing post-harvest losses, this parameter's continuous and precise monitoring is very important. To cater to the need in the present embedded system, DHT 11 is deployed. The sensor continuously detects the real-time temperature and humidity in the required unit and sends it to the end user. This DHT11 Temperature & Humidity Sensor features a temperature & humidity sensor compound with a calibrated digital signal output. By using the exclusive digital-signal technique and temperature & humidity sensing technology, it ensures high consistency and excellent long-term stability. This sensor includes an NTC temperature measurement component and a resistive-type humidity measurement component and connects to a high-performance microcontroller, offering excellent quality, fast response, anti-interference ability, and cost-effectiveness. In India climate change is in accordance with the session. Therefore, in summer there is high temperature, and in monsoon high humidity and variable temperature are observed. Therefore, the system is also suitable for providing controlled temperature and humidity as per the requirement of the end user or farmer for controlled warehouse application instead of open field or closed chamber.

Figure 2: DHT11 Temperature & Humidity Sensor.

GSM Module

The dual band GSM/GPRS based SIM900A modem from SIMCOM is used in the construction of this modem. It operates between 900 and 1800 MHz. The SIM900A has automatic band scanning capabilities. AT commands can also be used to adjust the frequency bands. The AT command allows you to configure the baud rate between 1200 and 11200. The internal TCP/IP stack of the GSM/GPRS modem allows you to establish a GPRS internet connection. SIM900A is a dependable and incredibly small wireless module. With its SMT design and very potent single-chip CPU that integrates the AMR926EJ-S core, this complete GSM/GPRS module offers you cost-effective options and modest dimensions.

Figure 3: GSM Module.

MQ2 Gas Sensor

The MQ2 gas sensor is a multipurpose and extensively utilized sensor that can identify various gases such as alcohol, smoke, carbon monoxide, hydrogen, propane, and methane. It is frequently used to detect gas leaks and smoke in safety systems, environmental monitoring, and home automation. The MQ2 gas sensor shown in figure 4 is deployed for detection of gas release from seed grain storage when seeds start degrading due to environmental effects. When seeds start degradation as a byproduct of various chemical and biological processes. The sensor uses digital mode, which senses the concentration of gas that is released in the warehouse.

Figure 4: MQ2 Gas Sensor.

The Display Section

The 16*2 line smart LCD is interfaced to ensure digital readout of thermal condition at the respective domain. The LCD is configured in sleep mode, which helps to save the power. Through the RF section, the humidity, thermal status, and gas concentration of the domain are also communicated to the end user's mobile as well as the serial terminal of the PC.

Embedded Firmware

The software is also known as firmware, which is required to fulfill the need of embedded system design [17,18]. The required code is designed using Arduino IDE using the embedded C language. The source code of the firmware is described through the following modules.

Main Programme
Functions or subroutines

USART ()
LCD ()
LCD_INIT
LCD_CMD
LCD_data
Calibration ()
Msdelay ()

The firmware realizes the sequential flow of execution. The USART () is developed to establish serial communication. The digital data is averaged over 10 samples and then availed for further processing. The function Calibration () plays a significant role in data processing. By using the microcontroller ATmega328 with the DHT11 humidity and temperature sensor, an electronic system can be developed to monitor the temperature and humidity of a warehouse very accurately, due to which the food grain, onion, can be stored more effectively. The DHT11 sensor provides digital output processed by the microcontroller. The Arduino provides a library file that includes a calibration equation and a calibration constant, which help to provide output in standard form. In firmware the necessary library file is called and used as per the requirement of the system. The objective of this work was to design an optimized technique by developing an electronic model to monitor the temperature and humidity and gas release of the warehouse automatically during day and night as per the requirement of food grain or onion in real time. Figure 5 shows the embedded C code successfully written and compiled to cater to the needs of the present investigation.

Figure 5: Embedded Firmware.

Result Discussion

The system under investigation interacts with the physical world, reads the signal, and processes it into real units [19,20]. Hence, it is essential to standardize the system to the temperature scale and humidity scale. Therefore, the system is standardized in the beginning and then implemented for what it has been designed for.

The following procedure is adopted for calibration.

Employing a standard temperature bath, the sensor of the present system is exposed to the temperature from 25°C to 60°C and temperature (t) with a standard temperature meter. The DHT11 sensor library file calibration factor and equation are used to measure temperature-dependent emf (VT) shown by the system, and it is recorded. The temperature-dependent emf VT and applied temperature (t) are observed, and the calibration constant is set to display temperature in °C. The temperature range selected is from room temperature to 60°C because, in the warehouse, the maximum temperature varies depending upon environmental variation, so the range is significant for the application.

Figure 6: Standardize the System to Temperature.

Similarly, the system is also extended to obtain humidity in relative units. For calibration, in the beginning a humidity-dependent voltage is measured for the entire range from room temperature conditions to the condensation of water. The voltages are measured up to the saturation point. For calibration, the humidity chamber, model Gayatri Scientific Ltd. Mumbai, is used. The humidity from 30 RH% to 90 RH% with an accuracy of 1 RH% is applied. The temperature range from 25°C to 95°C can be controlled.

The temperature as well as humidity of the chamber is controlled by using PID techniques. Keeping the temperature constant, the humidity applied to the sensor is varied between 30% RH and 90% RH. The data regarding EMF is collected and used for calibration.

Figure 7: Standardize the System to Humidity.

This library expression and calibration factor are used for further calculation. The expression is solved during firmware execution. The system is precisely calibrated, and it shows accurate readings of humidity in RH%.

Figure 8: Experimental Arrangement for Onion Status Detection.

For the gas detection sensor is inserted into a good and spoiled onion environment, and digital data is observed, and the observed factor is used for the detection of gas. The figure 8 shows the experimental arrangement for onion status detection. The onion status was continuously observed for five days from day and night mode, with temperature in °C and humidity in %RH. It is observed that temperature varies from 25°C to 36°C and humidity from 45% RH to 53% RH, and typically one day's data are represented in Figure 9. When a spoiled onion is added in the box, the gas concentration in the environment changes, and the system sends the message, which is shown on the mobile screen and depicted in Figure 10. From the observed reading, the system is ready for onion parameter detection in the warehouse. In the present investigation, the gas detection system only detects gases like methane, carbon monoxide, etc.; it is not specifically calibrated for specific gases. For the detection of gases, the sensor data sheet is considered for various gases detection. Furthermore, the system is calibrated specifically for onion-related gas detection.

Figure 9: Typical One Day Data of Humidity and Temperature.

Figure 10: Spoiled Onion Alert.

Conclusion

A major accomplishment in agricultural technology, the creation and application of a GSM-based smart electronic nose for onion preservation addresses important concerns with post-harvest onion storage. This creative system uses GSM technology, humidity and temperature, and gas sensors, like the MQ2 and DHT11, to monitor and control the ambient conditions of onion storage facilities. Methane, hydrogen, and carbon monoxide are among the gases released during the breakdown of onions that are efficiently monitored by the designed smart embedded system. The device may recognize early indicators of spoiling and initiate ventilation or other preservation techniques to maintain ideal storage conditions by real-time gas detection. Therefore, it concludes that the present system is an encouraging method for improving the preservation of onions and other perishable items, which is the GSM-based smart electronic nose. This technique could have a big influence on agriculture, boosting food security and financial stability for farmers by enhancing storage conditions, cutting losses, and encouraging sustainability. Innovation will be fueled by more research and development in this field, which will also increase the advantages of smart agriculture technologies.

Acknowledgement

With the view to keep pace with the state-of-art of the modern technologies, the Teacher Seed Money Research Grant of T. C. College, Baramati is pervasively supporting the research activities in diverse fields. Present Teacher Research Project (TRP) is the result of such college motivation research activity. T. C. College, Baramati has given financial support for this Research Project. Therefore, I would like to express my deep sense gratitude to the Commission for this support to carry out the present investigation.

Journal of Current Engineering and Technology