muondetector

Software for a Raspberry Pi based muon detector system using a u-blox GNSS module for precise timing. For more information visit our web page www.MuonPi.org and our Mediawiki.

ABSTRACT

This is a software solution for operating a Raspberry Pi mini computer and the u-blox NEO-M8 GNSS module's "timemark" feature together with a plastic scintillator + SiPM-based detector system to detect muons with a time stamping accuracy of up to a 20ns. Therefore, the software has to communicate with the Ublox GPS module through a serial interface using the ubx protocol. The good time accuracy is needed for correlating several independent detector units for the reconstruction of atmospheric muon showers resulting from ultra high-energy cosmic particles impinging on the earth's atmosphere. The software must be easy-to-use and runs in the background while synchronizing accumulated data with a central server.

DOWNLOAD

The latest binaries can be found as Debian packages with patch-notes and other release specific information in the "Releases" folder.

INSTALLATION

Raspberry Pi setup

1. Enable serial connections on the Raspberry Pi (use either one of the following):
   • Use sudo raspi-config > Interfacing options > Serial > Login Shell "no" > Enable serial port hardware "yes"
   • Manually add "enable_uart=1" to /boot/config.txt
2. Enable I2C communication on the Raspberry Pi:
   • sudo raspi-config > Interfacing options > I2C > Enable "yes"

Installation from latest stable release (recommended)

Version 1.1.2 is used as an example. Installing .deb Debian packages: sudo apt install <./filename> or on debian jessie sudo gdebi <'filename'>. An internet connection might be needed for automatically installing additional needed dependencies. On your Raspberry Pi:

1. Install "libmuondetector-shared_1.1.2-raspbian.deb"
2. Install "muondetector-daemon_1.1.2-raspbian.deb" Depending on the device of you choice, install the GUI for controlling the software via network connection or on the Raspberry Pi itself:
3. Install either one of the following depending on your system of choice:
   • "muondetector-gui_1.1.2-raspbian.deb" on a Raspberry Pi
   • "muondetector-gui_1.1.2-ubuntu_bionic-x64.deb" on a Ubuntu 18.xx machine
   • "muondetector-gui_1.1.2-windows-x64.zip" on a 64-bit Windows machine

Installation from source

The steps to building the daemon are as follows:

1. Install all dependencies
2. Enter the build directory
3. run cmake ../
4. run make package
5. enter output/packages
6. install the debian packages found there with sudo apt install ./<filename>.deb

Options

Possible options are:

MUONDETECTOR_BUILD_GUI This defaults to ON

MUONDETECTOR_BUILD_DAEMON This defaults to ON on a raspberry pi system and OFF otherwise. Note that you can not turn it on on a non-raspberry pi system.

TROUBLESHOOTING AND DEPENDENCIES:

Dependencies

When trying to create a Makefile with qmake (qt version 5.7.1 on raspbian) there will probably be errors. To install just get it from repository with apt-get install:

• "Project ERROR: unknown module(s) in QT: serialport" there is a missing library "libqt5serialport5-dev".
• "Project ERROR: unknown module(s) in QT: quickwidgets" there is a missing library "c".
• "Project ERROR: unknown module(s) in QT: svg" there is a missing library "libqt5svg5-dev".
• You also need to install "libcrypto++-dev libcrypto++-doc libcrypto++-utils"
• You also need to install "libqwt-qt5-dev" or "libqwt-dev".
• You may also install "lftp" for uploading acquired data to our server.
• For TDC7200 it may be required to manually add "dtoverlay=spi0-hw-cs" to /boot/config.txt

Cheat-Sheet Copy&Paste:

sudo apt install qtbase5-dev qtchooser qt5-qmake qtbase5-dev-tools pyqt5-dev qt5-qmake libqt5serialport5-dev libqt5svg5-dev libcrypto++-dev libcrypto++-doc libcrypto++-utils lftp libmosquitto-dev qtdeclarative5-dev libconfig++-dev libpigpiod-if-dev cmake file and either sudo apt install libqwt-qt5-dev or sudo apt install libqwt-dev

Troubleshooting

Version > 1.1.2

It may be when starting for the first time that, if the daemon is not started as a service, the data folder structure cannot be written due to insufficient rights. Starting the daemon with sudo-er rights should be avoided. Here, the folder structure can be created by hand to solve the issue: copy paste the hashed folder name from the error output of the daemon when started without folder structure and create the folder with sudo mkdir /var/muondetector/[Hashed Name] with notUploadedData and uploadedData as sub-folders. Then, change the user rights with sudo chown -R pi:pi /var/muondetector. When restarted, the daemon should be able to write the data.

Manjaro

The QT libraries are named differently in Manjaro. For successful installation, changes to the CMake files have to be made: In gui.cmake both occurences of qwt-qt5 have to be changed to qwt. Compillation can then start as usual with cmake <source_folder>, make and make install.

RUNNING THE SOFTWARE

Version < 1.1.2

On your Raspberry Pi, do:

1. sudo pigpiod -s 1 for setting the GPIO sampling rate to 1 MHz
2. start the daemon with muondetector_daemon <device> [options] where device is your serial interface (either "/dev/ttyS0" for Raspberry Pi 3 & 4 or "/dev/ttyAMA0" for Raspberry Pi 2). The options can be reviewed by adding -h. It is recommended to use the -c option on first start (if the configuration is not yet written to eeprom). On your network device or on your Raspberry Pi:
3. Start the gui with muondetector_gui on the device of your choice and measure some tasty muons!

Version >= 1.1.2

1. Make sure the daemon is properly installed. You can check the muondetector-daemon status with 'systemctl status muondetector-daemon.service'. It should show something like "loaded inactive" with a grey indication circle. Don't start the daemon yet. If the service is not recognized, the installation probably did not work correctly.
2. On first start: to log on the MQTT service, run the 'muondetector-login program' while the daemon is still offline. If you don't have a user account on our server yet, please send a mail to support@muonpi.org. Inside of /etc/muondetector/muondetector.conf you can set a configuration, for example you can set a unique station id in case you operate more than one station with one user account. Start the daemon with systemctl start muondetector-daemon.service (make sure it is also enabled by default using 'systemctl enable muondetector-daemon.service'). On your network device or on your Raspberry Pi:
3. Start the gui with muondetector-gui on the device of your choice and measure some tasty muons!