The objective was to develop a Gieger Muller Counter that would enable a common person to measure nearby nuclear radiations. The device should be equipped with LCD to provide a Highly Interactive User Interface. The device should also provide:
- Graphical Representation of CPM level
- Data Logging on Software
- USB Compatiblity
- Multi Gieger Tube Support
- SD Card Support
The device must be portable and should be battery operated to make it a handy and standalone device. The device was developed from scratch at TechShlok Laboratory. The process includes Architecture Designing, Components Selection, Architecture Implementation and Testing, PCB Designing, 3D Modeling and Assembling.
The brain of the device is Atmega2560 Microcontroller. It is a Low Power, High-Performance 8-bit Microcontroller. Its features and capabilites makes it best suitable for the device:
- 256kBytes of Flash – A good amount of flash eliminates program size limitations.
- 16 MHz Clock – High program execution speed
- 4 kBytes of EEPROM – Storing useful caliberation data
- Sleep Modes – Decresaing power consumption
To store real time captured data and information, SD Card and external EEPROM are used. The Real Time Clock(RTC) has been generated using external Intergrated Chip running on 3V Coin Cell. A USB battery charger along with boost circuit was designed to power the device via 3.7V Li-Ion battery.
The High Voltage Generator circuit with adjustable Output Voltage helps in operating a range of Gieger Tubes. A medium size QVGA Touch Screen was used to provide Interactive User Interface along with Graphical Reresentation of CPM levels.
Major Technologies Used:
- Serial Peripheral Interface(SPI) for SD Card Support
- Inter Integrated Circuit(I2C) Protocol for RTC, EEPROM interface
- Two Layer PCB design to make device portable
- Parallel Data Bus operation for LCD control
- USB Protocol for Software Data Logging
The firmware for the Atmel Micronntroller was designed using Embedded C language. The firmware handles different task like:
- Data exchange via SPI and I2C communication
- Controlling LCD and Touch Screen
- Data Communication using USB protocol
- Sievert and Roentgen Nuclear Radiation calculations
- Log the recordings in SD Card and EEPROM
The firmware also keeps track of Battery percentage, Memory used, amount of High Voltage Generated. An Application Software was also developed to log the captured data on Excel Sheet. The software also provides Graphical Representation of the data.
- Programming language – C#, Dot Net
- Database – Microsoft Excel, XML
- Development Tool – Visual Studio
- Operating System – Windows