In emergency situations, quick communication can be a matter of life or death. That's why the Emergency Calling System with SIM800 and Raspberry Pi 4 was created – to provide a reliable and cost-effective communication system during critical moments. In addition, this system is customizable and can be easily integrated with other sensors and devices, making it a versatile tool for emergency response.
With the ability to make voice calls, send SMS messages, and access the internet, the emergency calling system is a powerful solution for those seeking a dependable communication system during times of crisis. In this article, we will explore the components of the system and how to build it.
Components
The emergency calling system can be built using the following components:
- Raspberry Pi 4
- SIM800 module
- Power supply
- Antenna
- USB microphone and speaker
- A 3D-printed case to hold everything together
- IVR system
Raspberry Pi 4
The Raspberry Pi 4 is a single-board computer that can be used as the main controller for the emergency calling system. The Raspberry Pi 4 features a quad-core ARM Cortex-A72 processor and up to 8GB of RAM, making it an ideal platform for building an emergency calling system with an IVR system. It has various connectivity options such as Gigabit Ethernet, dual-band 802.11ac wireless, and Bluetooth 5.0. The Raspberry Pi 4 also features a GPIO header that can be used to connect various sensors and devices to the system.
SIM800 Module
The SIM800 module is a GSM/GPRS module that can be used for wireless communication. The module supports quad-band 850/900/1800/1900MHz and can be used to make voice calls, send SMS messages, and access the internet. The SIM800 module also features a UART serial interface that can be used to connect the module to the Raspberry Pi 4. The SIM800 module is easy to use and has low power consumption, making it an ideal choice for an emergency calling system with an IVR system.
Power Supply
The emergency calling system requires a reliable power supply to operate. The Raspberry Pi 4 requires a 5V 3A power supply, while the SIM800 module requires a 3.4V to 4.4V power supply. Therefore, a 5V 3A power supply can be used to power both the Raspberry Pi 4 and the SIM800 module.
Antenna
The SIM800 module requires an external antenna to establish a reliable wireless connection. A GSM antenna with an SMA connector can connect the SIM800 module to the external antenna.
USB Microphone and Speaker
The emergency calling system requires a USB microphone and speaker to make voice calls. The USB microphone can be connected to the Raspberry Pi 4 and used to pick up the user's voice during an emergency call. The USB speaker can be used to playback the voice of the emergency contact during the call.
3D Printed Case
Finally, the emergency calling system can be enclosed in a 3D printed case to protect the components and make it more portable. The Case should have openings for the USB microphone, speaker, power supply, and antenna.
IVR Software
An IVR (Interactive Voice Response) system is a technology that allows users to interact with a computerized system through voice or touch-tone input. In an emergency calling system, an IVR system can be used to provide pre-recorded instructions to the caller. To build an emergency calling system with an IVR system, you will need IVR software.
Setting Up the Raspberry Pi 4
Before we can start building the emergency calling system, we need to set up the Raspberry Pi 4. Here's how to do it:
- Download the latest version of the Raspberry Pi OS from the official website.
- Burn the Raspberry Pi OS image to an SD card using a tool like BalenaEtcher.
- Insert the SD card into the Raspberry Pi 4 and connect it to a monitor, keyboard, and mouse.
- Power on the Raspberry Pi 4 and follow the on-screen instructions to set up the operating system.
- Once the Raspberry Pi 4 is set up, connect it to the internet using a Wi-Fi or Ethernet connection.
Connecting the SIM800 Module
Once the Raspberry Pi 4 is set up, we can proceed to connect the SIM800 module. Here's how to do it:
1. Insert the SIM card into the SIM800 module.
2. Connect the antenna to the SIM800 module.
3. Connect the power supply to the SIM800 module.
4. Connect the USB to TTL converter to the SIM800 module.
5. Connect the USB to TTL converter to the Raspberry Pi 4.
6. Open the terminal on the Raspberry Pi 4 and run the following command to install the required libraries for the SIM800 module:
sudo apt-get install ppp usb-modeswitch wvdial
7. Create a new file called "wvdial.conf" in the home directory using the following command:
sudo nano ~/wvdial.conf
8. Add the following lines to the "wvdial.conf" file:
[Dialer Defaults]
Init1 = ATZ
Init2 = AT+CGDCONT=1,"IP","internet"
Modem Type = Analog Modem
Baud = 9600
New PPPD = yes
Modem = /dev/ttyUSB0
ISDN = 0
Phone = *99#
Password = { }
Username = { }
9. Save and exit the "wvdial.conf" file.
10. Run the following command to start the PPP connection:
sudo wvdial
11. If the connection is successful, you should see a message indicating that the PPP connection is up.
Setting Up the IVR System
An IVR system is required to enable automated voice communication. Here's how to set up the IVR system:
1. Install the necessary libraries using the following command:
sudo apt-get install asterisk mpg123
2. Create a new file called "emergencycall.conf" in the "/etc/asterisk" directory using the following command:
sudo nano /etc/asterisk/emergencycall.conf
3. Add the following lines to the "emergencycall.conf" file:
[emergencycall]
exten => s,1,Answer()
same => n,Wait(1)
same => n,Playback(emergency)
same => n,WaitExten()
4. Save and exit the "emergencycall.conf" file.
5. Open the terminal and run the following command to start the Asterisk service:
sudo systemctl start asterisk
6. Test the IVR system by calling the SIM card number connected to the SIM800 module. You should hear the "emergency" prompt, followed by a beep.
Building the 3D-Printed Case
A 3D-printed case is needed to hold everything together and protect the components from damage. Here's how to build the 3D-printed case:
- Download the STL files for the case from a 3D model repository.
- Use a 3D printer to print the case.
- Assemble the case by fitting the Raspberry Pi 4, SIM800 module, power supply, USB microphone and speaker, and antenna into the case.
Testing the Emergency Calling System
Once everything is set up and assembled, we can test the emergency calling system by following these steps:
- Make sure the Raspberry Pi 4 is powered on and connected to the internet.
- Make sure the SIM card is inserted into the SIM800 module and connected to the GSM network.
- Call the SIM card number connected to the SIM800 module.
- The IVR system should answer the call and play the "emergency" prompt.
- Speak into the USB microphone to communicate with the emergency response team.
- The emergency response team can hear the voice communication through the USB speaker and provide assistance.
Conclusion
Building an emergency calling system using a Raspberry Pi 4 and a SIM800 module is a cost-effective and efficient way to provide emergency communication. By following the steps outlined in this article, you can create an emergency calling system that can be used in various situations, including medical emergencies, natural disasters, accidents, and more. With an IVR system in place, you can enable automated voice communication and provide quick and effective assistance to those in need.
