How to build a satellite receiving station using a Raspberry Pi Space and satellites are something that only few people are fortunate enough to interact with. However, this is starting to change due to the rapid growth in capability of consumer electronics. In fact, you can receive and decode transmissions from satellites using only a Raspberry Pi, a USB software-defined radio receiver, and a few other cheap parts. In this blog post, I'll describe in detail how to put together such a system. Experimenting with receiving satellite signals is a lot of fun. Goal Build a satellite receiving station for amateur radio band cubesats using a Raspberry Pi. Parts needed Raspberry PiRTL-SDR or FUNcube Dongle Pro+ USB radio receiverLow-noise amplifier for the 70 cm amateur radio band e.g. Background The satellites we are going to receive are typically orbiting between 300 and 700 km altitude. The orbits of all satellites are regularly measured by NORAD radar and their orbital parameters (known as TLEs or Keps) are publicly available. Hardware construction Preparation
Raspberry Pi + OpenCV OpenCV is a suite of powerful computer vision tools. Here is a quick overview of how I installed OpenCV on my Raspberry Pi with debian6-19-04-2012. The guide is based on the official OpenCV Installation Guide on Debian and Ubuntu. Before you begin, make sure you have expanded your SD card to allow for the install of OpenCV. sudo apt-get -y install build-essential cmake cmake-qt-gui pkg-config libpng12-0 libpng12-dev libpng++-dev libpng3 libpnglite-dev zlib1g-dbg zlib1g zlib1g-dev pngtools libtiff4-dev libtiff4 libtiffxx0c2 libtiff-tools sudo apt-get -y install libjpeg8 libjpeg8-dev libjpeg8-dbg libjpeg-progs ffmpeg libavcodec-dev libavcodec53 libavformat53 libavformat-dev libgstreamer0.10-0-dbg libgstreamer0.10-0 libgstreamer0.10-dev libxine1-ffmpeg libxine-dev libxine1-bin libunicap2 libunicap2-dev libdc1394-22-dev libdc1394-22 libdc1394-utils swig libv4l-0 libv4l-dev python-numpy libpython2.6 python-dev python2.6-dev libgtk2.0-dev pkg-config cmake-gui .. makesudo make install python .
Plus de 50 idées pour votre Raspberry Pi Nous sommes nombreux à nous être procuré un petit ordinateur Raspberry Pi pour nous lancer dans des projets de ouf malade... C'est très cool, mais à part le classique Media Center XBMC, qu'avez-vous fait avec votre Raspberry Pi ? Si vous séchez niveau idées, voici une petite sélection que j'ai rassemblée au cours des derniers mois. J'imagine qu'il y a encore beaucoup d'autres idées et de tutos, donc n'hésitez pas à partager les liens dans les commentaires, je les rajouterai à ma liste. Merci ! En attendant, j'espère que ceux-ci vous donneront de l'inspiration... On peut donc en faire : Et si vous cherchez un moyen rapide et pas cher de faire un boitier de protection pour vos Raspberry Pi, pensez aux LEGO. Bon, je pourrai continuer comme ça toute la journée, mais va bien falloir que je m'arrête. Amusez-vous bien ! Rejoignez les 60492 korbenautes et réveillez le bidouilleur qui est en vous Suivez KorbenUn jour ça vous sauvera la vie..
Install OpenCV 2.3 with video support in Fedora 15 « Pratyush’s Weblog Much has changed since OpenCV 2.0.. android support, CUDA support, etc are up and running. So is the change in the method of installing OpenCV. So, i though to quickly jot down the steps to follow for a painless install. I must add, due to changes in gcc, removal of libv4l support from linux kernel, etc.. OpenCV 2.1 and 2.2 give loads of issues during install. 1. (i have tried copying the package names via OCR software and some editing as much as could be possible from the screenshot below) 2. And you are done !!! NOTE : due to requests for Ubuntu specific steps, i’ll put the changed steps in this post itself in a few days
RPi Low-level peripherals Back to the Hub. Hardware & Peripherals: Hardware and Hardware History. Low-level Peripherals and Expansion Boards. Screens, Cases and Other Peripherals. Introduction In addition to the familiar USB, Ethernet and HDMI ports, the Raspberry Pi offers the ability to connect directly to a variety of electronic devices. Digital outputs: turn lights, motors, or other devices on or off Digital inputs: read an on or off state from a button, switch, or other sensor Communication with chips or modules using low-level protocols: SPI, I²C, or serial UART Connections are made using GPIO ("General Purpose Input/Output") pins. Note that no analogue input or output is available. Links For further specific information about the Raspberry Pi's BCM2835 GPIOs, see: RPi BCM2835 GPIOs. Model A and B (Original) The Raspberry Pi Model A and B boards have a 26-pin 2.54 mm (100 mil)[1] expansion header, marked as P1, arranged in a 2x13 strip. Revision 1 PCBs also do not have the P5 header (see below). Useful P2 pins:
OpenCV Fedora 15 Compile OpenCV-2.2.0 From Source Herman Oosthuysen, GPL, 2011 Fedora Linux 15 Scope This is a brief guide to compiling OpenCV on Fedora 15, since the package included with Fedora does not work with video, which makes it rather useless. The biggest problem is finding a combination of software versions that work together and then a few small bugs need to be fixed which arose due to changes in the Linux kernel video drivers. Read my other guides on X264 and FFmpeg and compile them first. Download It is important to use the correct old version of FFmpeg-0.6.3. Go to Source Forge and download the older version 2.2.0 of OpenCV: Unpack it: $ tar -jxvf OpenCV-2.2.0.tar.bz2 $ cd OpenCV-2.2.0 $ mkdir release $ cd release Configure In my case, ccmake didn’t crash, but it also didn’t work. Build and Bug Fixes Build OpenCV: $ make Bug fix for error: ‘ptrdiff_t’ does not name a type $ gedit .. Install La voila!
Raspberry Pi Kernel Compilation The Raspberry Pi cannot run a vanilla Linux kernel. A patched version of the kernel is maintained by the Raspberry Pi Foundation and is available from their github Prerequisites To compile a kernel, you require dev-vcs/git to download the source code and genkernel to manage the build process. root # emerge --ask git genkernel Get the Kernel Source root # cd /opt root # git clone --depth 1 # ln -s /opt/linux /usr/src/linux Compile and Install the Kernel Note Compiling will take about 6 hours. Using genkernel you can build a linux kernel with support for many different features. Default Kernel In this example the configuration options from the running kernel are used to compile the new kernel. root # genkernel --kernel-config=/proc/config.gz kernel After the kernel has compiled it will be installed into the /boot folder. Kernel with initramfs root # genkernel --kernname=rpi --menuconfig all [Collapse] Kernel configuration
How to install FFmpeg & OpenCV under Fedora Linux - Wireless Video Sensor If you have FFmpeg already installed and is working fine together with ffplay, you can skip the FFmpeg Step.If you don't trust your current FFmpeg or OpenCV unstall them this way: A--- cd "The original folder you installed them from" e.g. for OpenCV cd OpenCV-2.1.0 or cd ffmpeg-0.5.1 B--- make uninstallC--- make clean allD--- cd ..E--- rm -rf OpenCV-2.1.0 or rm -rf ffmpeg-0.5.1 FFmpeg step: 1--- Download FFMpeg 2--- su 3--- tar xzf ffmpeg-0.5.1.tar.gz 4--- cd ffmpeg-0.5.1 5--- . 6--- make all 7--- make install all The –-enable-shared option during configuration ensures compatibility between LGPL licence of ffmpeg contents and BSD licence of OpenCV. ADDITIONAL IMPORTANT STEPS (before installing OpenCV)A few header files of ffmpeg may need to have a symbolic link created. Open the folder where library files of ffmpeg have got installed in your system. ln -s libavcodec/avcodec.h avcodec.h ln -s libavformat/avformat.h avformat.h ln -s libavformat/avio.h avio.h ln -s libavutil/avutil.h avutil.h 5--- .