Providing an easy and contemporary work environment with modern technologies while taking distinctive security measures for the workplace is extremely important and is one of the positives provided to the employee by the company, so using smart locks for doors and dispensing with traditional keys contributes in some way to achieving this goal. Using the NodeMCU DevKit ESP8266, an open-source platform, with Radio Frequency Identification (RFID) technology with an electric lock that enhances the security of the doors [1], [2]. In this paper, a door security system was implemented using ESP8266 and RFID, unlike traditional door security methods. One of the main advantages of the system lies in its ability to enable the opening of doors through a single RFID card and for several doors within the company or institution according to the powers granted to the cardholder [3], [1]. This makes it easier to open room doors and enhances employee comfort while maintaining safety protocols. The use of RFID in the system ensures comprehensive monitoring recording and helps in analyzing access patterns, thus enhancing security management in the organization. Often when using these technologies there is a fear of what if a power outage occurs in the system. Especially in small institutions that do not have the high financial liquidity to provide expensive alternatives or in countries where power outages are frequent. Without power, the system stops working making it impossible for the employee to access his room and finish his tasks. Therefore, it's important to find a cost-reliable alternative [4]. The system was designed to address this issue by using energy allowing for the use of a power bank, as a backup solution in case of emergencies. In situations, like power outages caused by fires or electrical issues the system continues to function. This proactive approach demonstrates the system's dependability and its ability to manage risks effectively. In essence, the system provides a solution that offers convenience, efficiency, and flexibility enabling organizations to enhance their security infrastructure to meet workplace requirements while ensuring maximum safety and security.[1], [2], [3], [4], [5]

In the years there has been a noticeable rise, in the integration of smart technology into our daily routines. A study by Kafdi et al. (2017) introduced a Bluetooth system designed for a door enabling users to manage and oversee their homes. By utilizing an ATmega 32 controller and a smartphone app linked to Bluetooth along with a door-facing camera the system aims to provide security and assistance for individuals with disabilities. However, the research paper omitted details, on any outcomes or the energy consumption required for its operation [6]. Putra et al. (2018) introduced a home door security system using Raspberry Pi and IoT, with RFID and a camera. The system uses the Raspberry Pi as a control unit, and an RFID sensor to detect the card, and when the card is detected, the camera takes a picture. The system also uses a relay lock and a solenoid to lock/unlock the door [7]. Faisal et al. (2019) introduced a system to enhance the security and convenience of the doors, using e-KTP with RFID as an electronic key, motion sensor, and backup power supply. An RFID reader was used to read the electronic Indonesian ID card (e-KTP) to open the door, and the motion sensor was used to detect human movement and trigger an alarm. They also added the e-KTP tag manually to the system [8]. Solestanti et al. (2020) presented a system using 5 NodeMCU ESP-12E boards, 4 of which act as clients, and one acts as a server. The clients monitor and control the door of the house and manage parts of the house. Monitoring and control are done through a mobile phone application connected to a Wi-Fi network. The paper did not provide any preliminary results or specific endpoints for the system [9]. Gupta et al. (2022) presented an IoT-based smart door lock system that allows users to control doors within a specified range using Bluetooth technology and an Android application [10]. Okafor et al. (2022) presented a prototype of a door control system using voice recognition and RFID technology, with an Arduino Uno controller that operates the system components. The paper did not address the initial results of the system, nor the mechanism and energy expenditures required for it [11].

Hardware Requirements:

NodeMCU DevKit ESP8266: It is an open-source IoT platform. It consists of firmware written in the Lua scripting language, featuring a 32-bit controller on a chip (ESP8266-ESP12E WiFi SoC) manufactured by Espressif Systems.

The company has packaged the ESP8266 into a small board with multiple functions, a USB port for serial communication with a computer or other device, and multiple ports or pins called general purpose input/output (GPIO) for accessing sensors, actuators, etc., which can be easily programmed by many open-source programs such as Python and Arduino Integrated Development Environment, it also features built-in Wi-Fi on the chip[12], [13]. As shown in Figure 1.

Solenoid for Electric Door Lock: It consists of a moving iron core surrounded by a cylinder-shaped copper coil. It consists of electrical, magnetic, and mechanical parts. When electrical current flows through the coil, it creates a magnetic field within the solenoid. The field strength is directly related to the magnitude of the current flowing through the coil causing the iron piston to move within the coil.

When the power is cut off, the piston returns to its original position because of the applied mechanical force, the figure 2 shows a Schematic Diagram of the Solenoid[14]. The type used in work operates with 12-volt electrical power and an electrical current of approximately 1.7 amps when activated as shown in figure 3.

• RC522 RFID module: Long-range radio frequency identification (RFID) is a general term for non-contact technology that uses radio waves to automatically identify people or objects. There are many identification methods, but the most common is to store the serial number that identifies a person or thing, on a small chip attached to the antenna. The combination of an antenna and a microchip is called an RFID transceiver or RFID tag, and it works in conjunction with an RFID reader[15]. RFID uses radio frequencies to read information from small devices called tags or transceivers (transceivers). The RFID tag will recognize itself when it detects a signal from a compatible device, i.e. an RFID reader. RFID is a flexible, easy-to-use identification technology that is well-suited for automated operations. RFID combines features not available in other identification technologies[16], [17].

Long-range RFID technology RFID is based on the principles of electromagnetic action, where the main components of the RFID tag are the tag chip and the antenna, where the chip contains information and is connected to the tag antenna. The information contained or stored in this chip will be transmitted or read via electromagnetic waves after the antenna tag receives electromagnetic wave emissions from the reader antenna. This RFID reader will forward the information to the application server at the same time[1].

• Buzzer: It is used to issue audio signals to the user to indicate the occurrence of a certain condition, such as the correct card and successful opening or the wrong card.

• 
  LCD (Liquid Display): The liquid display is used to display important information to the user, such as a Welcome message, and print the name of the cardholder.

   

• PIR (Passive Infrared Radiation): The motion sensor (pir) is used to detect movement in the area around the door. A signal from the motion sensor is used to activate the system when motion is detected, alerting the user or performing specific actions[18].

• Power Bank: The power bank is used as a power source for the system in the event of a main power outage.

• The bank can be charged by mains electricity and can be used to power essential devices such as NodeMCU and RFID modules in emergencies, as well as the door lock. 

   

Software Requirements:

Arduino IDE (Integrated Development Environment): Code can be written, assembled, and uploaded to ESP8266 boards using an Arduino IDE. Users can create programs called sketches with the IDE; these sketches are saved as files with the (.ino) extension[19], [20].

Design Implementation:

The proposed system uses the NodeMCU DevKit ESP8266 that connects to the motion sensor, an RFID card reader, and a screen through the I2C (it is a serial communication protocol), in addition to using a relay that was used to control the solenoid lock used for the door, as it operates with a voltage of 12 volts, so the system sends a signal to the relay, which in turn will open the lock. One power bank was also used, operating at a voltage of 5 volts through a USB port, to supply the system with electrical energy, and another 12-volt outlet was used to supply the lock through the relay.

The idea of using a special power bank for the system enabled the system to be power-isolated with the ability to work in the event of a power outage in the building or company, especially in emergencies.

Figure (6) shows the system design.

How the system works:

After connecting all the parts of the system and the system starts working, you will have several scenarios for the system, which are as shown: 

Scenario A:

The absence of any movement in front of the door: When the system is turned on, the ESP checks the movement near the door through the PIR sensor. If there is no movement, the system does not turn on the screen (turning off the screen completely), to save energy.

Scenario B:

There is movement in front of the door: If the PIR senses movement, the system will activate the screen (welcome screen) and request that the card be placed on the reader (Please Put Your Card), then the reader will scan the card:

1. 1- If the card is incorrect (the person is not allowed to enter the room), the system will activate the buzzer to emit three rapid intermittent alerts to notify that the card is invalid. Simultaneously, an error message ("Sorry Wrong Card") will be displayed on the screen.

    

2. 2- If the card is valid (the cardholder is allowed to enter the room), the system will activate the buzzer to emit a single welcoming alert. Additionally, a welcome message will be displayed on the screen, showing the cardholder's name. Subsequently, a signal will be sent to the relay to unlock the door, allowing entry.

   The flowchart in Figure (7) shows how the system works.

This project aims to develop a smart door opening system using electronic components such as ESP8266, RFID, LCD, PIR motion sensor and electric door lock solenoid. The system features the following:

• Low power consumption: The system stays in low power standby mode when no one is near the door.

• Power check: The current passing through the system was measured and found to be close to zero when the screen and card reader were off. When someone passes by, the screen turns on and the reader is ready, which increases the power consumption. The power consumption increases further when the card is read, and the lock is unlocked. Then it returns to low power level again.

• Security: Prevents unauthorized access using RFID cards, and the buzzer adds an audible alert in case of correct reading and in case the person is not authorized to enter with a different alert.

• Convenience: Facilitates the entry process for authorized users by automatically opening the door when they approach it.

   

Experimental results:

Experiments have proven that the system works with high efficiency, as the screen is activated as soon as someone passes through the door, and RFID cards are read accurately while saving energy effectively when there is no movement in front of the door. The system provides a practical and safe solution for access control and access monitoring for private places such as offices. Continuous power testing has shown that the system's power consumption is very low in standby mode, and gradually increases according to the system activity from screen powering on to unlocking. The system has proven its security by allowing only authorized people to open the door. The functions of the buttons, PIR sensor and buzzer have been successfully tested in various scenarios. Switching from direct power to battery is done in case of power failure.

doors of government departments, universities, and company room doors that require permission to enter the rooms. The NodeMCU DevKit ESP8266 was used as a low-cost and low-power microcontroller, an RC522 RFID module, a motion sensor, a display, and a Solenoid for Electric Door Lock. The system is characterized by its low cost in general, in addition to its low energy consumption, especially since a special power bank was used for it to ensure the provision of energy at all times, even when the building’s main power is cut off. The presented system is easy to program as it uses Arduino IDE software, which is open source. It also enables people to carry one card to open several doors if permission is granted to them. The company manager would have the authority to enter ten rooms, for example. Instead of carrying ten keys (a private key for each room), he will carry one RFID card to enter all the rooms. The use of a motion sensor also enables the system to be effective if someone passes by the door or wants to enter, but the rest of the time the system will be semi-sleep (especially during off-hours or on holidays) and thus the system will reduce its energy expenditure. The system also provides secure entry into the room, as the doors will be opened only for cardholders authorized to enter. Using the screen and button in the presented system enables you to alert people who are trying to enter through sight (using the screen) or through hearing (using the button). 

I am very happy to present this work on Securing Office Doors, with NodeMCU ESP8266 based on RFID Technology, and express my deep gratitude to those who offered their valuable time and guidance in my time of need. It is a great honor to do this work at the esteemed Department of Computer Science, College of Computer Science and Mathematics, Tikrit University, Iraq.

1. Hanif Batubara, I. P. Sari, and N. ’ Afifah, “PENGARUH MODEL PEMBELAJARAN BERBASIS MASALAH BERBANTUAN SOFTWARE CABRI 3D TERHADAP HASIL BELAJAR MAHASISWA PADA MASA PANDEMIC COVID,” vol. 7, no. 1, 2021.

2. D. Yulianto Wijaya and A. Yulianto, “Prototype of Smart Door Using RFID Technology with Internet of Things (IoT),” 2021. [Online]. Available: www.arduino.cc

3. N. Okorafor, F. Opara, O. G. Nwaji, N. C. Onyebuchi, and F. Kelechi, “Automatic Door Unit Radio Frequency Identification (RFID) Based Attendance System,” 2013. [Online]. Available: http://www.rfidjournal.com/article/view/3321]

4. N. Okorafor, “RADIO FREQUENCY IDENTIFICATION (RFID) BASED ATTENDANCE SYSTEM WITH AUTOMATIC DOOR UNIT,” 2012. [Online]. Available: https://www.researchgate.net/publication/280558358

5. R. Suhail, “Automated door access based on RFID using Arduino,” European Alliance for Innovation n.o., Mar. 2021. doi: 10.4108/eai.27-2-2020.2303113.

6. S.A. Engineering College and Institute of Electrical and Electronics Engineers, SMART DIGITAL DOOR LOCK SYSTEM USING BLUETOOTH TECHNOLOGY. 

7. I. T. Putra, W. K. Raharja, and M. Karjadi, “PUSH BUTTON SISTEM KEAMANAN PINTU RUMAH MENGGUNAKAN RASPBERRY PI BERBASIS IOT,” Jurnal Ilmiah Teknologi dan Rekayasa, vol. 23, no. 3, pp. 166–176, 2018, doi: 10.35760/tr.2018.v23i3.2466.

8. M. A. Faisal and E. Sitompul, “Door Security System Using e-KTP RFID Reading and Passive Infrared Sensor,” 2019.

9. S. R. Sulistiyanti and F. A. Setyawan, “Smart Home Controlling and Monitoring System using Multiboard Client-Server Internet of Things (IoT),” Journal of Engineering and Scientific Research, vol. 1, no. 2, p. 69, Mar. 2020, doi: 10.23960/jesr.v1i2.19.

10. K. Gupta, N. Jiwani, M. H. U. Sharif, M. A. Mohammed, and N. Afreen, “Smart Door Locking System Using IoT,” in 2022 International Conference on Advances in Computing, Communication and Materials, ICACCM 2022, Institute of Electrical and Electronics Engineers Inc., 2022. doi: 10.1109/ICACCM56405.2022.10009534.

11. O. C. S., N. S. U., A. T. L., O. V. C., and J. U. C., “Door Access Control Using RFID and Voice Recognition System,” Int J Res Appl Sci Eng Technol, vol. 10, no. 3, pp. 157–163, Mar. 2022, doi: 10.22214/ijraset.2022.40453.

12. M. Wijayanti, “PROTOTYPE SMART HOME DENGAN NODEMCU ESP8266 BERBASIS IOT,” JUIT, vol. 1, no. 2, 2022.

13. R. Firmansyah, M. Yusuf, P. P. Surya Saputra, M. Eko Prasetyo, F. Mahardi Mochtar, and F. Agung Kurniawan, “IoT Based Temperature Control System Using Node MCU ESP 8266,” 2020.

14. M. F. Badr, “Modelling and Simulation of a Controlled Solenoid,” in IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing, Nov. 2018. doi: 10.1088/1757-899X/433/1/012082.

15. I. P. Sari, A. H. Hazidar, M. Basri, F. Ramadhani, and A. A. Manurung, “Penerapan Palang Pintu Otomatis Jarak Jauh Berbasis RFID di Perumahan,” Blend Sains Jurnal Teknik, vol. 2, no. 1, pp. 16–25, May 2023, doi: 10.56211/blendsains.v2i1.246.

16. A. M. Pemanfaatan et al., “InfoTekJar : Jurnal Nasional Informatika dan Teknologi Jaringan Attribution-NonCommercial 4.0 International. Some rights reserved,” vol. 5, no. 1, 2020, doi: 10.30743/infotekjar.v5i1.3229.

17. G. Casella, B. Bigliardi, and E. Bottani, “The evolution of RFID technology in the logistics field: A review,” in Procedia Computer Science, Elsevier B.V., 2022, pp. 1582–1592. doi: 10.1016/j.procs.2022.01.359.

18. S. A. Akinwumi, A. C. Ezenwosu, T. V. Omotosho, O. O. Adewoyin, T. A. Adagunodo, and K. D. Oyeyemi, “Arduino Based Security System using Passive Infrared (PIR) Motion Sensor,” in IOP Conference Series: Earth and Environmental Science, IOP Publishing Ltd, Feb. 2021. doi: 10.1088/1755-1315/655/1/012039.

19. M. Tupac-Yupanqui, C. Vidal-Silva, L. Pavesi-Farriol, A. Sanchez Ortiz, J. Cardenas-Cobo, and F. Pereira, “Exploiting Arduino Features to Develop Programming Competencies,” IEEE Access, vol. 10, pp. 20602–20615, 2022, doi: 10.1109/ACCESS.2022.3150101.

20. Ismail Setiawan, “Komparasi Kinerja Integrated Development Environment (IDE) Dalam Mengeksekusi Perintah Python,” SATESI: Jurnal Sains Teknologi dan Sistem Informasi, vol. 2, no. 1, pp. 52–59, Apr. 2022, doi: 10.54259/satesi.v2i1.784.