Open Dosimeter

Abstract

1. Introduction

N. Ger, A. Ku, J. Lopez, N. R. Bennett, J. Wang, G. Ateka, E. Anyenda, M. Rosezky, P. Kilavi, A. S. Wang, & K. Shaker, "OpenDosimeter: Open hardware personal X-ray dosimeter" _Commun Eng_ 4, 207 (2025)

Additionally, if you prefer to order directly from the PCB manufacturer, you can download the gerber file also located in the hardware directory or at the OpenDosimeter Kitspace page.

Our open-source hardware and software dosimeter offers an afordable solution for real-time, self-monitored X-ray radiation exposure. With a total component cost of roughly $90, this device provides an accessible option for radiation monitoring to promote broad access to radiation safety. This project is a derivative of the Open Gamma Detector, with the main new feature being the effective dose calculations (in Sieverts) converted from the detected X-ray spectrum.

2. Objective

Open-source project for a low-cost battery-powered personal X-ray dosimeter! Using a custom PCB powered by a Raspberry Pico with an X-ray sensor (LYSO crystal + SiPM assembly)

This project demonstrates how Arduino can be applied to a real-world Internet of Things (IoT) problem.

3. Key Features / Modules

• Open Design: Hardware and software designs are fully open-source, enabling reproducibility and customization
• Affordable: Total cost ~$90, see here and cost breakdown →
• Compact: 73 mm x 42 mm x 23 mm (with the case)
• Programmable: Drag and drop firmware files. Either a Raspberry Pi Pico or a Raspberry Pi Pico 2 can be used — they are drop-in replacements for each other — see the software folder for which pre-compiled .uf2 file to use
• Battery powered: Current version has a capacity of up to 20 hours per full charge (<70 mA @ at 3.7V, 1200 mAh battery)
• Accuracy: Currently reliable between around 0.1 µSv/h to 1 mSv/h (±25% accuracy) in the photon counting range
• Buzzer: Built in buzzer allows for optional audible warnings when dose rate exceeds predefined limit (default set to 5 µSv/h)
• Calibratable: Using Am-241 from any household ionization smoke detector for spectral/dose calibration
• Real-time: Direct feedback on radiation exposure, compared to passive dosimeters (e.g., OSL or TLD badges) requiring external readout
• Logging: The last 10 hours of dose values are stored on the device; extracted through USB connection and our web interface here

4. Technology Stack

5. System Requirements

General requirements for this technology stack — check the README for exact versions.

• See the project README for exact requirements
• Git (to clone the repository)

6. Installation & Setup

git clone https://github.com/OpenDosimeter/OpenDosimeter.git
cd OpenDosimeter

Full setup instructions are in the project README.

7. Future Enhancements

Suggested extensions you can add to make this your own project.

• Add a mobile dashboard using Blynk or Firebase
• Store readings in a cloud database for history charts
• Add alerts via SMS / Telegram when thresholds are crossed

8. Viva / Review Questions

Common questions examiners ask for projects in this domain.

1. Which microcontroller / board and sensors are used and why?
2. How does the device send data (Wi-Fi, MQTT, HTTP, Bluetooth)?
3. Where is the sensor data stored and visualised?
4. How is power consumption managed?
5. How would you secure the device and its communication?

9. Source Code & License

This project is developed by OpenDosimeter and published on GitHub under the GNU General Public License v3.0. Please follow the license terms and credit the original author when you use or modify this code.