- Building a Raspberry PI for FRC - using WPILibPi
- TL;DR Config Details
- Introduction
- Theory of operation
- Prepare for Competition
- Config Details
- make sure you have a raspi 3 or 4 with picam
- build microSD card (minimum 8GB)
- on first boot
- install python extensions
- pull git repository
- install GStreamer and plugins
- Copy scripts to the home directory
- rename/renumber your raspi (going off the outside network)
- validate camera
- verify opencv/python and picamera
- optional - install support for h264 feed
- optional - install window system
- misc
- Troubleshooting
- Archived sections
- >
- >
The Raspberry Pi (raspi) is an inexpensive and entirely adequate processor capable of both video capture and processing. Outfitting a raspi to integrate well with FRC network tables and competition requirements is a non-trivial system-administration task and so the FRC folks have kindly provided the community with a canned raspi disk image that can be installed onto a raspi and get you running in under 20 minutes.
Among the built-in conveneniences offered by the WPILibPi image:
- WPI libraries for network tables and FRC interop utilities.
- The opencv image processing library with bridges to java, c++ and python.
- A disk partitioning scheme that can be configured for read-only or read-write access. During competition, the read-only mode reduces the chance that the disk will be corrupted by during robot start & stop.
- An easy-admin webapi that allows you to:
- configure IP addressing (DHCP vs static IP)
- configure team number
- establish which camera script runs on the robot
- configure camera ports and binding
- toggle between read-write and read-only mode
- to monitor the state of the raspi (cpu, network traffic, etc).
- A service architecture that ensures that your camera/vision server program is always running.
- Clutter-reduction: elimination of a variety of utilities on the default
raspi image that consume precious space or cycles including:
- wolfram mathematica
- x windows and associated desktop tools
- WIFI disabling: disallowed during FRC competition and disabled in WPILibPi (this is an inconvenience at first).
Basic idea: use the web WPILibPi dashboard to control and monitor your raspi. If you change your raspi's name, this link won't work, but you can either enter the new hostname or its static ip address like this.
If you need to configure/reset any persistent value, you must make the raspi Read-Write. After configuration is complete, make sure it's in Read-Only mode. A reboot with cause filesystem to be reset to read-only mode.
Establishing the team number makes is possible for the raspi to connect to the robot's network tables. Robot connections are only possible if the raspi and the robot are on the same network. In other words in the 10.49.15.* address range.
Establishing a static IP address is one way to ensure that the raspi is
in the robot's address space. It's also a way for our DriverStation
dashboard to identify each raspi reliably. The standard name,
wpilibpi.local, will not work reliably when multiple raspis are
on the same network. You can also change the hostname of your raspi.
Now, a static IP would still be of potential use, but not absolutely
necessary to disambiguate multiple raspis.
You can upload your custom python "cameraService" via the web interface
via the Application tab. This will persist across reboot and is the
preferred/suggested way of managing custom vision code. The script,
~/runCamera, is used to launch your program. Each time you upload a
new vision script, runCamera is automatically updated to point to
your new script. Your script is uploaded to the file ~/uploaded.py and
here's what runCamera looks like to make it happen:
#!/bin/sh
### TYPE: upload-python
echo "Waiting 5 seconds..."
sleep 5
export PYTHONUNBUFFERED=1
exec ./uploaded.py
This form of runCamera requires that your python script be written to include
the shebang to python3. In
other words, the first line of your script must be:
#!/usr/bin/env python3Here's a trivial example whose output can be view in the Vision Status
console when enabled. Generally debugging output of vision scripts
should be disabled during competition to prevent unnecessary network
network traffic.
#!/usr/bin/env python3
import time
while 1:
time.sleep(5)
print("tick");
time.sleep(5)
print("tock");Here's a shell script (startVision.sh) to load a standard git-based
Vision solution:
#!/bin/bash
cd /home/pi/spartronics/Vision/2019
exec ./runPiCam.py --robot roborio --config greenled_dbcam8Here's a shell script (startH264player.sh) to start the h264player:
#!/bin/bash -f
cd /home/pi/spartronics/Vision/h264player
node appRaspi.jsA number of startSomething.sh scripts can be found in our repository and it's quite simple to manually edit ~/runCamera to launch the desired script. Here's an example with a few options commented out.
#!/bin/sh
### TYPE: upload-python
echo "Waiting 2 seconds..."
sleep 2
exec ./startVision.sh
#exec ./startH264player.sh
#export PYTHONUNBUFFERED=1
#python ./startSleeper.pyNote that if you manually copy or create a file on the raspi for this
purpose that it must be executable. You can make a file executable
via: chmod +x yourfile. And verify that it is executable via
ls -l yourfile. Here is a before and after:
# before
% ls -l yourfile
-rw-r--r-- 1 pi pi 17201 Feb 2 13:37 yourfile
# after
% ls -l yourfile
-rwxrwxr-x 1 pi pi 17201 Feb 2 13:37 yourfileOnce we've built-out our variation of a standard raspberry pi (see below), we can create a disk image that should be used to build out new microsd cards. In order to minimize the time to duplicate the image, its best to work with an 8BG sdcard. Our customizations could be made available in the release section of our Vision github following these instructions, however there appears to be a limit on the size of such tarballs and we have yet to complete this task. To get around this limitation FRC has elected to "zip" the image. Interestingly, disk-duplication utilities like Etcher are able to handle .zip-ed images.
Note that any disk image will reflect a specific machine identity
(see here) (ie: its static ip). After
cloning this disk image, you'll need to boot your new raspi and reconfigure
its static ip. The distinction between driver and vision cameras is
characterized by static ip and the camera process that runs after each
reboot. For driver camera, we use the uv4l script and for vision camera
we employ python plus runPiCam.py.
This link
shows how to squeeze a bigger partition onto a smaller disk (but it requires windows).
NB: the older version of the software is available from warez sites and seems
simpler than the more modern version.
- use the WPILibPi dashboard to ensure you're operating in Read-Only mode. You can use these commands to toggle between ro and rw:
# make it read-only
ro
# make it read-write
rw
# ro is an alias for:
# sudo /bin/mount -o remount,ro / && sudo /bin/mount -o remount,ro /boot
# rw is an alias for:
# sudo /bin/mount -o remount,rw / && sudo /bin/mount -o remount,rw /bootWPILibPi disables both wifi and bluetooth via these contents of
/etc/modprobe.d/raspi-blacklist.config.
#wifi
blacklist brcmfmac
blacklist brcmutil
#bt
blacklist btbcm
blacklist hci_uartDuring debugging and provisioning of a raspi, you may find it useful to enable the wifi. If you do so, make sure to disable it before competing.
After commenting out the two wifi entries and rebooting verify that the wifi is active:
% ifconfig wlan0
wlan0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether b8:27:eb:47:2d:bd txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0Check which wifi networks are available:
% sudo iwlist wlan0 scan | grep ESSID
ESSID:"Tortellini"
ESSID:"WIFI"
ESSID:""
ESSID:"CenturyLink1238"
ESSID:""
ESSID:"xfinitywifi"Add network password to /etc/wpa_supplicant/wpa_supplicant.conf:
country=US
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
network={
ssid="BISD-OPEN-WIFI"
key_mgmt=NONE
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP
auth_alg=OPEN
}
# if your network has a password replace key_mgmt with psk="YourPassword"To reconfigure wifi network:
% wpa_cli -i wlan0 reconfigure
% ifconfig wlan0If you have two routes to the internet you may need to look at the routes.
% ip route
default via 192.168.0.1 dev eth0 src 192.168.0.8 metric 202
default via 192.168.1.1 dev wlan0 src 192.168.1.74 metric 303
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.8 metric 202
192.168.1.0/24 dev wlan0 proto kernel scope link src 192.168.1.74 metric 303Here, 192.168.1 and 192.168.0 are our two networks and each have a default route.
More information on configuration wifi can be found here.
-
a properly duplicated (up-to-date!) microsd is essential issurance for a competition.
The Vision tree includes a script, 'rpi-clone' in the tools directory. See tools/rpi-clone/README.md (in the Spartronics repo which will be cloned into this image in a later step (pull git repository) for instructions.
Following are details on how to buy, provision and operate a raspi based on the WPILibPi image. Additional customizations are offered to maximize utility in the context of Spatronics4915. These are the steps needed to build a raspi that can be used as a base-image. If you already have a base-image available, use it skip these steps. In that case, remember to set the static IP and drive script appropriate for the raspi's role on the robot.
You can buy raspis and raspi cameras at a number of sites, here are a few examples:
- The basic instructions are here, with the following modifications.
- The easiest imager to use now is the Raspberry Pi Imager. The current version as of this writing (02.04.22) is 1.7. This imager will understand how to unpack images inside .zip files.
- The actual installation instructions begin at Installing the image to your MicroSD card and the image is in the WPILibPi repo. As of this writing, the current version is 2021.3.1.
- you can verify that the built-in webserver is operational by pointing your browser to http://wpilibpi.local. Note that you must be on the same network for this to work. Typically its best to plug your laptop and the pi into the same network access point (wifi hub/bridge). Note also that you may have problems with this if you have more than one raspi on the same network.
- notice the Read-Only | Writable selector at the top of the page. If you need to make any changes, the disk must be writable. (in practice, setting the read/write status is best done just after first login, by entering 'rw' at the prompt)
- ssh into wpilibpi.local (user is 'pi', password is 'raspberry')
- make sure disk is writable by entering 'rw' (status is shown in parens in the command prompt)
sudo raspi-config(use Tab, Esc and Arrow keys to navigate)System Options- Hostname (set host name here - reflect how camera is used)
Localisation Options/Locale- set locale (en_US.UTF8 - make sure that's the only one marked)
Localisation Options/TimeZone- time-zone (America/Los Angeles)
Interfacing Options- Enable connection to Raspberry Pi Camera (pi3/2019)
- Enable I2C (for camera switcher)
Performance Options- Consider raising GPU memory to 256MB
- you will be required to reboot after the raspi-config process. After the reboot, the Pi will be available at '.local', where '' is the hostname that you set above
- make sure disk is writable by entering 'rw' at the prompt
- when you login, make sure date/time is set correctly - set time manually if needed
sudo date 0204150622 # (format is MMDDHHMMYY) - change user password
% passwd # respond to prompts, old was raspberry, new: teamname (spartronics) - update and cleanup (recover diskspace)
sudo mount -o remount,rw / sudo mount -o remount,rw /boot sudo apt-get update sudo apt-get upgrade
- reboot
- install some needed packages
sudo apt-get install python3-pip git vim tree lsof i2c-tools lshw sudo apt-get install rsync parted util-linux mount bsdmainutils dosfstools
- clean things up
sudo apt-get clean sudo apt-get autoremove
# following may be present in wpilibpi, but shouldn't hurt
sudo python3 -m pip install picamera
sudo python3 -m pip install numpy
sudo python3 -m pip install -U pyntcore
(the last one, pyntcore, may take a while, as some dependencies may need to be installed.)cdmkdir -p spartronicscd spartronicsgit clone https://github.com/Spartronics4915/Vision
sudo apt install gstreamer1.0-tools gstreamer1.0-plugins-base gstreamer1.0-plugins-bad gstreamer1.0-plugins-goodcd ~/spartronics/Vision/tools/DriverCamScripts/RPi
cp -rp .??* * ~cd ~/spartronics/Vision/tools/DriverCamScripts/RPi
sudo cp run /service/cameraIf you are done with needing access to the outside network, then it's time to set up each camera with a static address.
You can establish a static IP via the WPILibPi dashboard. If you haven't renamed your Pi yet, it can be accessed via wpilibpi dashboard. If you have named your Pi, replace 'wpilibpi' with the Pi's name.
Using the WPILibPi dashboard, set one of the following static IP addresses, based on the camera's use case:
Name IP Address Port
---
frontcam 10.49.15.11 5805
backcam 10.49.15.12 5806
upcam 10.49.15.13 5807
vision 10.49.15.10
gateway 10.49.15.1
DNS server 10.49.15.1
Subnet mask 255.255.0.0
On the dashboard, under 'Network Settings', change the 'DHCP' to 'Static', and fill in the IPv4 address field with the appropriate value from the table above.
On the dashboard, under 'Vision Settings', make sure that the 'Client' button is on, and fill in the team number (4915).
Also, since we are NOT using a USB camera, make sure to click the 'Remove' button if there is a camera listed in this section.
Always remember to click 'Save' on each page when you are done with your changes.
-
vcgencmd get_camerashould report this:supported=1 detected=1
-
raspistill -v -o test.jpg. This will only work if you remove the picamera from the Connected Camera list on the Vision Settings tab. See troubleshooting if you have problems. -
(deprecated) to use picam as opencv videostream (ie: without picamera module):
sudo modprobe bcm2835-v4l2
% python3
>>> import cv2
>>> import picamera
>>> import networktablesThe sub-$25 pi camera can operate at up to 90 fps and includes a native H264 encoder. This is far superior to most current usb2 webcams and offers a number of controls not usually present in a webcam. A raspi has two CSI connection points, but can apparently support only a single picam connected at the point nearest the HDMI.
H264 is a very efficient video solution on raspberry pi due to
its GPU-based implementation. The hard part is delivering
the resulting video stream to a web browser for integration with our
Dashboard. We have explored three technologies for this and currently
suggest that h264player is the preferred solution.
h264playeruses tcp-based websockets to deliver the raspivid stream to a browser. No fancy STUN negotiations take place, but to make the pixels visible in the browser we employ a javascript h264 decoder. Once the pixels are decoded, we rely on an opengl YUV canvas for their display. The more modern html5 video element and media streams aren't employed by this approach and so its major downside is that it consumes extra load on the driver station. See here for more.webRTCis the newest and shiniest of streaming techs. It resolved the biggest issue for broad-deployment of streaming through a complex routing negotiation system called ICE, which requires external STUN and/or TURN services. It was built to integrate well with web browsers using a native inbuilt h264 decoder. But it failed for us in the context of the FRC Field Management System. Since we have very little time operating in that environment it is very difficult to diagnose and resolve the problem. Another difficulty we encountered related to the fragility of the disconnect/reconnect process. In dual camera setup, we found it necessary to work around this difficulty (esp with uv4l) by keeping two streams open throughout the match.rtspis an older tech for streaming that doesn't appear to "gel" with web browsers. It does appear to have the same advantages (over webrtc) that h264player does in terms of traffic routing. An open source app, VLC, has support for decoding and displaying an rtsp feed. On the raspi side, several rtsp options are available with gstreamer being the likely candidate. For our purposes, interacting with 3rd party app windows would present an awkward driverstation experience especially for multicamera switching based on network table events.
Support for h264player is checked in to our Vision repository here. To install the support, you simply pull the Vision repository to your raspi and wire it into the WPILibPi application like so:
% mkdir ~/spartronics
% cd spartronics
% git clone https://github.com/Spartronics4915/Vision
% cd Vision/h264player
% cp startH264player.sh ~Note that moving from one version of WPILibPi to another, we may need to update the node_modules associated with the h264player. Here's how:
% cd ~/spartronics/Vision/h264player
% rm -rf node_modules
% npm install # may produce version warnings which should be okay
# ./startH265player.sh # may produce version errors, etc. if so then:
% npm upgrade express
# and try again (etc)Here are the contents of startH264player.sh:
#!/bin/sh
echo "Starting h264player ---------------------"
cd /home/pi/spartronics/Vision/h264player
exec node appRaspi.jsNote that h264player requires node and the installation details are
found here. Next, we edit ~/runCamera
to look like this:
#!/bin/sh
echo "runCamera waiting 2 seconds ----"
cat /proc/device-tree/model
echo "\n"
sleep 2
# source the file
. ./startH264player.sh
# Here's an python alternative, should you wish to debug restart mechanisms
# export PYTHONUNBUFFERED=1
# exec ./tickTock.pyNote that we'ver reduce the waiting time from 5 to 2 seconds. This was
done in order to increase the responsiveness of camera-switching triggered
by driver actions and is a consequence of the big hammer approach for
clean shutdowns employed by our variant of h264player/serverBase.js,serverRaspi.js.
The startSleeper.py is commented out but offers a simple way to validate
the FRC application supervisor or to temporarily disable h264player.
We experimented with this tech and it failed us during competetions. Please refer to file history for more details.
We experimented with this tech and it failed us during competetions. Please refer to file history for more details.
Details here
sudo apt-get install --no-install-recommends xserver-xorg
sudo apt-get install --no-install-recommends xinit
sudo apt-get install xfce4 xfce4-terminal- for FAT32 thumbdrives, the desktop environment can be used to
mount and eject. In this case, the contents are found under
/media/pi. Via CLI:sudo mount /dev/sda1 /media/usb -o umask=000. You might need tosudo mkdir /media/usb. It's possible that support for "exfat" (large-file FAT) isn't present on the system. Install via:sudo apt-get install exfat-fuse exfat-utils. Finally, remember that portable FAT doessn't have user permissions (or any security for that matter). Get used to all files being owned by root, etc. - if you have a ext4 thumbdrive, you may need to manually mount it:
sudo mount /dev/sda1 /mnt/usbdrive. (you might need to mkdir) If you don't know the device id:lsblk. - remember to eject/umount the thumbdrive!
pi@wpilibpi(rw):~$ pstree
systemd─┬─agetty
├─avahi-daemon───avahi-daemon
├─cron
├─dbus-daemon
├─dhcpcd
├─ntpd───{ntpd}
├─sshd─┬─sshd───sshd───bash
│ └─sshd───sshd───bash───pstree
├─svscanboot─┬─readproctitle
│ └─svscan─┬─supervise───multiCameraServ───3*[{multiCameraServ}]
│ ├─supervise───netconsoleTee
│ └─supervise───configServer───5*[{configServer}]
├─syslogd
├─systemd───(sd-pam)
├─systemd-journal
├─systemd-logind
├─systemd-udevd
└─thd
Here's a subset of above with a custom python script (multiCameraServer replaced by python3).
├─svscanboot─┬─readproctitle
│ └─svscan─┬─supervise───python3
│ ├─supervise───netconsoleTee
│ └─supervise───configServer───5*[{configServer}]
The svscanboot process subtree is all about keeping your camera server process
running. The default cameraServer detects the installed cameras and writes
a files to /boot/frc.json. This file can be configured from the WPILibPi
dashboard under Vision Settings. If you don't want the built-in
discoverable cameras (USB or raspicam) from being locked, you can remove
them from the list of enabled cameras. You can also configure settings
like capture resolution, brightness and auto-exposure via this interface.
The results of your configuration activities trigger updates to /boot/frc.json
but you can also manually edit this file (using vi, of course).
Here's a list of services listing on the ports. The WPILibPi dashboard is listening on the standard http port. Port 1740 is the network tables service. 22 is ssh and 1181 is the mjpeg streaming port.
netstat -n -a | grep LIST
tcp 0 0 0.0.0.0:1740 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:1181 0.0.0.0:* LISTEN
tcp6 0 0 :::22 :::* LISTEN
>>> print(cv2.getBuildInformation())
General configuration for OpenCV 3.4.7 =====================================
Version control: v2020.1.1
Platform:
Timestamp: 2019-12-31T20:55:19Z
Host: Linux 4.15.0-1064-azure x86_64
Target: Linux 1 arm
CMake: 3.13.4
CMake generator: Unix Makefiles
CMake build tool: make
Configuration: Release
CPU/HW features:
Baseline: VFPV3 NEON
requested: DETECT
required: VFPV3 NEON
C/C++:
Built as dynamic libs?: YES
C++11: YES
C++ Compiler: /__w/1/s/work/2019-12-31-FRCVision/raspbian10/bin/arm-raspbian10-linux-gnueabihf-g++ (ver 8.3.0)
C++ flags (Release): -isystem /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/include/arm-linux-gnueabihf -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfpu=neon -fvisibility=hidden -fvisibility-inlines-hidden -O3 -DNDEBUG -DNDEBUG
C++ flags (Debug): -isystem /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/include/arm-linux-gnueabihf -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wundef -Winit-self -Wpointer-arith -Wshadow -Wsign-promo -Wuninitialized -Winit-self -Wsuggest-override -Wno-delete-non-virtual-dtor -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfpu=neon -fvisibility=hidden -fvisibility-inlines-hidden -g -Og -DDEBUG -D_DEBUG
C Compiler: /__w/1/s/work/2019-12-31-FRCVision/raspbian10/bin/arm-raspbian10-linux-gnueabihf-gcc
C flags (Release): -isystem /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/include/arm-linux-gnueabihf -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Winit-self -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfpu=neon -fvisibility=hidden -O3 -DNDEBUG -DNDEBUG
C flags (Debug): -isystem /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/include/arm-linux-gnueabihf -Wno-psabi -fsigned-char -W -Wall -Werror=return-type -Werror=non-virtual-dtor -Werror=address -Werror=sequence-point -Wformat -Werror=format-security -Wmissing-declarations -Wmissing-prototypes -Wstrict-prototypes -Wundef -Winit-self -Wpointer-arith -Wshadow -Wuninitialized -Winit-self -Wno-comment -Wimplicit-fallthrough=3 -Wno-strict-overflow -fdiagnostics-show-option -pthread -fomit-frame-pointer -ffunction-sections -fdata-sections -mfpu=neon -fvisibility=hidden -g -Og -DDEBUG -D_DEBUG
Linker flags (Release): -Wl,-rpath -Wl,/__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/opt/vc/lib -rdynamic -Wl,--gc-sections
Linker flags (Debug): -Wl,-rpath -Wl,/__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/opt/vc/lib -rdynamic -Wl,--gc-sections
ccache: NO
Precompiled headers: NO
Extra dependencies: dl m pthread rt
3rdparty dependencies:
OpenCV modules:
To be built: calib3d core dnn features2d flann highgui imgcodecs imgproc java ml objdetect photo python3 shape stitching superres ts video videoio videostab
Disabled: world
Disabled by dependency: -
Unavailable: cudaarithm cudabgsegm cudacodec cudafeatures2d cudafilters cudaimgproc cudalegacy cudaobjdetect cudaoptflow cudastereo cudawarping cudev js python2 viz
Applications: perf_tests apps
Documentation: NO
Non-free algorithms: NO
GUI:
GTK+: YES (ver 3.24.5)
GThread : YES (ver 2.58.3)
GtkGlExt: NO
Media I/O:
ZLib: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/arm-linux-gnueabihf/libz.so (ver 1.2.11)
JPEG: build-libjpeg-turbo (ver 2.0.2-62)
WEBP: build (ver encoder: 0x020e)
PNG: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/arm-linux-gnueabihf/libpng.so (ver 1.6.36)
TIFF: build (ver 42 - 4.0.10)
JPEG 2000: build (ver 1.900.1)
HDR: YES
SUNRASTER: YES
PXM: YES
Video I/O:
DC1394: NO
GStreamer: YES
base: YES (ver 1.14.4)
video: YES (ver 1.14.4)
app: YES (ver 1.14.4)
riff: YES (ver 1.14.4)
pbutils: YES (ver 1.14.4)
libv4l/libv4l2: NO
v4l/v4l2: linux/videodev2.h
Parallel framework: pthreads
Trace: YES (with Intel ITT)
Other third-party libraries:
Lapack: YES (/__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/arm-linux-gnueabihf/libopenblas.so)
Custom HAL: YES (carotene (ver 0.0.1))
Protobuf: build (3.5.1)
OpenCL: YES (no extra features)
Include path: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/src/opencv-3.4.7/3rdparty/include/opencl/1.2
Link libraries: Dynamic load
Python 3:
Interpreter: /usr/bin/python3 (ver 3.7.3)
Libraries: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/arm-linux-gnueabihf/libpython3.7m.so (ver 3.7.3)
numpy: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/include/python3.7m/numpy (ver undefined - cannot be probed because of the cross-compilation)
install path: lib/python3.7/dist-packages/cv2/python-3.7
Python (for build): /usr/bin/python3
Java:
ant: /usr/bin/ant (ver 1.10.5)
JNI: /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/jvm/jdk-11.0.1/include /__w/1/s/work/2019-12-31-FRCVision/stage3/rootfs/usr/lib/jvm/jdk-11.0.1/include/linux
Java wrappers: YES
Java tests: NO
Install to: /usr/local/frc
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Test with raspistill -p "0,0,640,480".
-
did you enable the camera with
sudo raspi-config? -
is
multiCameraServerusing it? Make sure that the camera is removed from theVision Settings. Save is only available if the system isWritable. If that fails to resolve the problem upload the tick-tock script above to fully disable multiCameraServer. -
is another program using it? uv4l? your python script?
# this will show you if a uv4l process is running % ps -ef | fgrep uv4l # this will show you all the processes that are LISTENING on a port % netstat -an | grep LISTEN # this will show you which process is listening on port 8080 it # returns a process number (pid) % sudo fuser 8080/tcp # and this finds the program associated with a pid % ps -ef | grep yourpid
-
is there a problem with the video device?
cd /dev ls -l | grep video # look for devices owned by group video
It should look like this:
crw-rw---- 1 root video 29, 0 Mar 12 20:34 fb0 crw-rw---- 1 root video 245, 0 Mar 12 20:34 vchiq crw-rw---- 1 root video 249, 0 Mar 12 20:34 vcio crw-rw---- 1 root video 246, 0 Mar 12 20:34 vcsm crw-rw---- 1 root video 81, 0 Mar 12 20:34 video0
If you see something else, try:
% sudo rm /dev/video0 % sudo reboot
-
make sure that the service is disabled (described above).
-
look at the running services via:
% systemctl list-units --type=service
wpilibpi webpage doesn't appear at http://wpilibpi.local
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are there more than one raspis on the network? Then you should be using static IP addresses and using the ip address as the URL. Make sure only one is on the network, then try again. You can configure static ip addressing via the Network Status page. Here's a typical setup:
# Configure IPv4 Address Static # IPv4 Address 10.49.15.XXX # where XXX is in the range 10-20 # Subnet Mask 255.255.255.0 # Gateway 10.49.15.1 # DNS Server 8.8.8.8
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is configServer running?
% ps -ef | grep configServer # should produce: root 294 288 0 Jan28 ? 00:00:00 supervise configServer root 299 294 0 Jan28 ? 00:29:24 /usr/local/sbin/configServer pi 15895 15900 0 10:46 pts/1 00:00:00 grep --color=auto configServer
-
is someone listening on port 80?
% netstat -an | grep :80 # this shows that a process is listening on port 80 tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN # and this shows someone connected to the port tcp 0 0 10.49.15.11:80 192.168.0.4:52793 ESTABLISHED
-
is the correct server running? Are there any indications of badness in the logs?
-
can we
traceroute 10.49.15.5(ie to the driverstation) -
does stun protocol work?
#start the stun-server on driverstation node-stun-server#contact the stun-server from the client node-stun-server -s 10.49.15.5 (ie driverstation)
Test by pointing your browser to http://wpilibpi.local:8080 (or static IP)
-
is someone listening on port 8080?
If not, try starting uv4l manually:
% uv4l --driver raspicam --auto-video_nr -- more parameters here --
- if that fails have you installed all the correct uv4l components? Have you verified that the camera is working?
- if a manual restart works, then it's an issue of getting it to start after every reboot.
-
uv4l doesn't auto-launch after reboot
There are two ways to auto-launch:
- via systemctl
- via
Applicationtab of wpilibpi webapp.
We currently recommend running it via
Applicationto eliminate the chance of contention during boot. You can upload the uv4l shell script via theUploaded Python fileoption even if it's not a python script. Consult the example above for syntax.
Currently we recommend installing vision services through
the wpilibpi webapp's Application panel. Your script may fail due to syntax errors or missing resources. The
application manager will repeatedly attempt to relaunch
your script even in the error case. Best to debug the
script manually before installing it as the application.
- make sure to enter the correct team number into
Vision Settings - make sure robot is on the same network as raspi
- check the console output in the wpilibpi webapp
With the change to using GStreamer, NodeJS is no longer needed. Left for archival purposes
- Installing NodeJS seems to be somewhat problematic - the versions available in apt-get are old and don't seem to be configured correctly. Perusing various sets of instructions on the net led to installing from the 'unnofficial-builds.nodejs.org' site, specifically the 16.9.1 LTS version. Get it with the folliwing
and install with the following:wget https://unofficial-builds.nodejs.org/download/release/v16.9.1/node-v16.9.1-linux-armv6l.tar.gzsudo mkdir -p /usr/local/lib/nodejs tar xvzf node-v16.9.1-linux-armv6l.tar.gz sudo mv node-v16.9.1-linux-armv6l /usr/local/lib/nodejs/ ln -s /usr/local/lib/nodejs/node-v16.9.1-linux-armv6l/bin/node node ln -s /usr/local/lib/nodejs/node-v16.9.1-linux-armv6l/bin/npm npm- Test for successful install by checking versions:
In this case, the commands return 'v16.9.1' and '7.21.1', respectively.node -v npm -v
Following probably not needed. It looks like the new base image already does this
To change your raspi name, you must log-in manually. Note that using the raspi-config tool is insufficient for this task due to frc conventions. Also note that this step may not be needed since we generally prefer to rely on ip addresses (since we have multiple raspis to manage).
# renaming your raspi may not be necessary # first the usual step sudo hostnamectl set-hostname drivecamfront # next, the frc fixup: # sudo edit /etc/hosts with nano or vi to look like this: 127.0.0.1 localhost ::1 localhost ip6-localhost ip6-loopback ff02::1 ip6-allnodes ff02::2 ip6-allrouters 127.0.1.1 drivecamfront # after editing this file, reboot the machine and potentially the router
This section is outdated - left for archival purposes
Here's a link to a variety of methods to accomplish this task. The larger your microsd, the longer this process will take. On Linux and MacOS you can use this:
sudo dd if=/dev/diskN of=~/Desktop/myRaspiImg bs=512; # where N is your microSD, you can findit either via: # `mount` or `diskutil list` # to monitor its progress, you can periodically send it a signal # (either background the dd process or perform this in another shell) while true; do sudo killall -INFO dd; sleep 60; done # on linux use -USR1Note well: if your "working disk" is much larger than your target disk, you can reduce the time it takes to perform the duplication through the use of a piclone-like facility, like this script, coupled with a usb-mounted target microsd card on your master pi.
backup /dev/sd01 # one parameter: target disk device /dev/sda[1-N]And to create a duplicate, reverse the process:
# make sure the /dev/diskN is unmounted either via: # `sudo diskutil unmountDisk /dev/diskN` or `sudo umount /dev/diskN` sudo dd if=~/Desktop/myRaspiImg of=/dev/diskN bs=512;Unfortunately, this particular script wasn't able to successfully duplicate an FRC vision system, perhaps because the number of mount points and file systems is unusual.
End of archival section