p–ISSN: 2723 - 6609 e-ISSN: 2745-5254

Vol. 5, No. 6 June 2024 http://jist.publikasiindonesia.id/

Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 6 June 2024 2798

Capacity Limit Measuring Tool on Children's School Bags

Using Esp32 Microcontroller and GPS Tracker

Putri Oktari

Jaka Persada Sembiring

*Correspondence

ABSTRACT

When children go to school, they often carry books, stationery, and other utensils

in their bags. The heavy weight of a child's bag can hurt their health, such as problems

with the spine and poor posture (Faridah, 2023). Therefore, it is crucial to ensure that the

weight of the child's bag remains within safe limits for their health. Using a backpack is

considered the best method to distribute the load symmetrically, thus reducing pressure

on the spine (Trisnawati, 2020). Choosing a backpack with two shoulder straps is

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2020).

Pain in the back of the body can be described as discomfort that is felt locally or

involves nerve roots, or both, that are localized around the thoracolumbar or lumbosacral

region (Handayani, 2023). The results of a survey conducted by the Archives of Disease

in Childhood on 1,403 students showed that as many as 61.4% of them experienced pain

in the lower back. This incident is more commonly experienced by students aged 12-17

years (Setiaji, 2020). These findings reflect that pain in the lower back is a common

complaint, especially in 12-17-year-olds, which is a period of rapid growth. Another

factor that plays a role is the habit of carrying backpacks with excessive weight when

children should not carry more than 10% of their body weight [2].

Paramurthi, 2023).

The purpose of this study is to design and implement a capacity limit measuring

device on children's school bags that can help overcome the problem of lack of attention

to the weight of backpacks which can cause the risk of injury and pain in children's backs.

Research related to capacity limit measuring tools on children's school bags using

ESP32 microcontroller and GPS Tracker (Ratih, Saraswati, Antari, & Negara, n.d.). This

research is titled "Smart Bag Weight Detection Equipped with Loadcell Sensor with

Brainstorming Method". The tool uses an Arduino Uno with a loadcell sensor that can

load a capacity of up to 5 kg. In addition, the HX711 module converts the change of

resistance into voltage. The voltage is then converted to ground, which is displayed on

Display) 2 x 16 characters. The way this tool works is to detect if the weight of the load

exceeds the safe limit, then there is a danger warning and alarm that the weight of the

load is not suitable to be carried if the weight of the load exceeds 10-15% of the body

weight. The weight sensor performs well with calibration of less than 5 % accuracy

difference with perpendicular position weighing measurements [5].

In 2021, the research was entitled "Design and Build a NODEMCU-Based

Backpack Security System ESP8266 with Android Application Notifications". In this

study, NodeMCU and GPS module function to help find out the position of the backpack

so that its existence status can be known. The vibration sensor and buzzer function to help

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condition, a notification will be displayed on the "Secure Bag" application and the

location of the bag can be seen. The location accuracy level on the Android application

was 95% from three trials with different locations (REVITA LARASATI, 2021)

The research is titled "Smartbag with Arduino-Based Security System with PIR

Sensor and GPS via SMS". The design of programs and algorithms on backpacks with

quick response has been carried out and obtained good results because overall the design

consisting of emergency alarms, motion detectors, and tracking devices that can be

controlled via SMS has been appropriate and can be applied to backpacks (Mohammad

Farid Susanto, M. Azam Gresa Mahendra & Anggraeni, 2020)

2. Tool Planning

The design of the tool aims to design a scheme of the device system for measuring

the capacity limit of children's school bags.

3. Prototyping

Prototyping is done to implement the design into a physical prototype.

4. Final Evaluation

The final evaluation aims to evaluate the system's response to bag weight variations,

the accuracy of the loadcell, and the sensors to the success of the system.

Tool Work System Flow Chart

send the current location to the telegram, and if the weight of the bag exceeds the

maximum capacity that the child can carry, the buzzer will automatically turn on and

notify the telegram that the child is carrying a load that exceeds the capacity. If the load

has been reduced then the buzzer will stop.

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Figure 1. Tool Flow Diagram

Schematic Networks

Schematic circuits are created to combine the components used with fritzing

applications. It can be seen that the LCD is connected to an I2C pin, where I2C will

minimize the use of ports on the ESP32. The LCD will display the weight of the bag (load

weight) as well as the maximum weight of the backpack. Furthermore, there is an HX711

module that is connected to an Arduino Uno pin as a module to calculate the weight of

the load on the load cell. Then there is a 3x4 keypad that is useful for inputting the child's

weight. Then there is a buzzer that functions as a warning alarm when the load on the

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At this stage, the researcher designs the tool in the form of a 3D design design. The

3D design of the bag and tools can be seen in the image below:

Load Cell Testing

Load cell testing is the first step to obtaining the necessary measurement results and

data. The test was carried out by applying a load on the load cell and was carried out 3

times. After that, look at and record the change in the weight of the load read by the

loadcell, and compare the weight of the load read by the loadcell with the actual weight

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load placed on the sensor load cell are displayed. The measurements and calculations

obtained from the 1 pcs lunch box are as follows:

Average load weight = Total = 0.47+0.47+0.47 = 0.47 Kg

Amount of Data 3

Error = Average Weight x 100 = 0.47 x 100 = 97 %

Actual Weight 0.46

LCD Testing

LCD testing is carried out to find out if the LCD can display the display according

to the given program and can receive input from the keypad. When the device is turned

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GPS testing is carried out to test the accuracy of distance data on the device. So that

parents can find out the position of the bag used by the child. Here are the images from

the GPS test.

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= 3.30 Kg

Conclusion

With the development of this system, it is hoped that it can increase the awareness

of parents and teachers about the burden of bags carried by children. This smart solution

is expected to be the first step in preventing back injuries due to excessive burden on

children. Further research can be conducted to optimize the system and expand its

application to the wider educational environment.