DIY OSD update
Filed under: Development, FPV, Hardware, Robots, Video
Late update, but video is working as expected, GPS is working to some extent, but because of local weather I havent really tested it outdoors… I’m considering changing video transmitter and power system however. I’m currently running on 1S 160mAh batteries with a stepup regulator to 5v to a 10mw transmitter, which gives a really lousy battery time for the video system, also I’ve got too many batteries flying around at the moment I think.. Limiting to a bit fewer might be a good idea. Currently, there’s a battery for the video link/osd, one built into the camera, one for motor/rc receiver/servos, and one in the rc transmitter, 4 batteries in total of various sizes etc… a pain to charge them all. Hooking up the videolink and OSD to ESC/BEC is a trivial change and would remove a lot of cruft (stepup module etc), but will also add the EMC from motor/ESC to handle for the videolink etc as it’s a completely separate system today.
I’ve also upgraded so I’m using a mobius actioncam. Everything all in all means the system will draw more power and weigh more as well. Removing some batteries and running from the mains system would be really nice.
qmake project custom install and files being installed as non-executable
I had some issues with creating a custom install target from a qmake pro file for a project today and everything took me quite some time to get working I’m embarassed to say. This was done to create make install_ptest target for a yocto build, but the files kept turning up non-executable in the rpm’s and install directory. In the end, I got it working by adding the executable keyword to the CONFIG of the target, in addition to the no_check_exist.
PTEST_FILES += \
$$ROOT_SOURCE_DIR/tests/service_tests/test_runner.py \
$$ROOT_BUILD_DIR/tests/service_tests/tst_service_tests
ptest.depends += $(first) sub-tests tests
ptest.path = /usr/lib/AnyApp1/ptest
ptest.files = $$PTEST_FILES
ptest.CONFIG = no_check_exist executable
INSTALLS += ptest
QMAKE_EXTRA_TARGET += ptest
I hope this helps you if you run into the same problem as I had some issues finding information about that specific flag or the problem.
Build ppa package
Filed under: Debian, Development, Linux, Ubuntu
To build a package for ppa distribution, you need some tools. To “cross compile” for releases, for example i386 and amd64 packages on the same machine, takes some more work with schroot, dchroot etc. I’ll start with explaining how to create a “local” package for your own host, I’ll add another entry on how to do an i386 package from amd64. Everything is done on ubuntu 14.04 amd64 machine in this case, and I’m rebuilding dbus.
In short you need:
- apt-get install build-essentials dpkg-buildroot schroot gpg
- gpg –gen-key
- apt-get build-dep dbus
- mkdir dbus-amd64 && cd dbus-amd64
- apt-get source dbus
- export DEB_SIGN_KEYID=
- cd dbus-directory
- make changes.
- dch -i
- dpkg-source –commit
- dpkg-buildroot -i -I
If you plan on publishing your deb packages to launchpad or some such, you need to create an account and add a ppa. This is simple and done via the http://www.launchpad.net webpage. The webpage also gives you good upload information. Note that they require signed files, so signing must work for you first.
8. Create account on launchpad.
9. Export the gpg generated key to hkp://keyserver.ubuntu.com:11371 (easiest to do via Passwords and Keys tool
10. Import the key to launchpad using the key fingerprint.
11. Create a new PPA from the launchpad dashboard
12. dput ppa: dbus_1.6.18-0ubuntu4.4_source.changes
The package will be built by launchpad on its own, this may take some time..
Remote DBus continued (using your own program)
Filed under: Communications, Development, Linux
Continuing the previous thought on running DBus remotely using d-feet to check how it looks etc, this time, I wanted to call the DBus from my own program. Just write the DBus code as you would to query the DBus interface locally.
#!/usr/bin/env python import dbus import dbus.service from dbus.mainloop.glib import DBusGMainLoop BUS_NAME="org.freedesktop.DBus" OPATH="/" bus = dbus.SessionBus() obj = bus.get_object(BUS_NAME, OPATH) iface = dbus.Interface(obj, BUS_NAME) lala = iface.GetId() print lala
Then the magic comes in running the application.
DBUS_SESSION_BUS_ADDRESS="tcp:host=192.168.X.Y,port=Z" ./dbus-hello.py
DBus remote connection
Filed under: Communications, Development, General, Linux
In a project I’m working on at the moment we wanted to remotely monitor a DBus session bus. The system in question has several buses available using different users and systemd. d-feet can connect and monitor remotely via TCP. The following code will allow you to connect to a remote DBus on a target development board for example.
First copy the original session.conf to separate configuration files for each user.
cp /etc/dbus-1/session.conf /etc/dbus-1/session.conf.<username> cp /etc/dbus-1/session.conf /etc/dbus-1/session.conf.<username2>
Then for each of the newly created configuration file, add the following configuration but with different port numbers and correct username director in /run/user. The ip address should be the IP of the connecting host, not the server. Edit session.conf.<username> and add:
<listen>tcp:host=<ip>,bind=*,port=<port>,family=ipv4</listen> <listen>unix:path=/run/user/<username>/dbus/user_bus_socket</listen> <listen>unix:tmpdir=/tmp</listen> <auth>ANONYMOUS</auth> <allow_anonymous/>
The systemd script is rewritten to use a specific conf file for the specific user trying to start the DBus.
Edit /lib/systemd/system/dbus-session@.service and rewrite the ExecStart line as follows.
ExecStart=/usr/bin/dbus-daemon --config-file /etc/dbus-1/session.conf.%i --nofork
This allows you to connect using d-feet or other dbus applications (potentially, you should be able to connect for example other services over the network to the new DBus….).
Choose “connect to other bus” and use as bus address:
tcp:host=<targetIp>,port=<port>
Done. Hopefully.
Testing out RasPlex
I decided to try out RasPlex after having run OpenElec and RaspBMC for about half a year, and before that XBMCbuntu for a few years. I’ve been using plex server on my file server for a few months already and plex on the tablets/phones to stream movies, tv shows, etc while in bed. I haven’t had that much time with RasPlex yet, but I’m really impressed so far, especially when you start looking at what type of infrastructure it enables. I’m now using the same chain of applications for my tv, phones, tablets, and laptops, this is something I’ve never been able to before (if you except NFS/SMB solutions with VLC or some such video player, which has proven unstable for the phone/tablet cases in my case, high def videos will stutter a lot among other things).
My main problem with the entire setup is that my fileserver is a bit too weak to transcode 1080p on the fly, it is a D525 Atom CPU however, and I didn’t see this usecase when I bought it, so I’ll have to live with it for now ;).
All that said, I’m still very happy with XBMC, but I feel that RasPlex so far has given a more… mature feeling. It seems to work very well with no big hickups so far, the UI on RaspBMC and OpenElec was really slow, something that still holds true in RasPlex, but it is better.
Gps issues
Filed under: Communications, Development, Linux
Been working for a few days with three different GPS modules (different builds etc) and I’m getting the same problem with all of them. They are pretty much giving out complete garbage at all settings. At 9600 bps 8n1 it gives out patterns at least. Just unreadable. I thought it might be ubx protocol but probably not.
I feel like I’m doing something really stupid but I can’t figure it out. Serial port problem? What else could be wrong?
Saleae16 Logic16 100M 16 Channel Logic Analyzer
Filed under: Development, Hardware, Linux, Robots, Ubuntu
I got a clone of the Saleae16 Logic16 100M 16 Channel Logic Analyzer a few days ago to test some of the arduino stuff I’ve been working on for the last few months.
I was at first really annoyed because the software simply refused to work, I tried it on 4 different computers, ubuntu 13.10 64bit, Windows 7 32bit and 64 bit and same error for all of them, logic too slow for speed, try reducing blah something. My searches came up with very little info.
So in the end I found the sigrok package and compiled myself (old version in Ubuntu lacked saleae support) and was pleasantly surprised! It works and actually seemed to be an OK package! There are a few things to do before that which wasn’t obvious, you need to extract firmware from the Saleae software suite and so on for example. Also there are a few bugs in the graphical interface that I found so far. I’ll try to get them reported ASAP and possibly do some work on them. I’ll get back to this topic a bit later as it wasn’t completely obvious how to get it running at all points, for now however, it works;).
Raspberry Pi + 2x Arduino Nano V3.0
Filed under: Development, General, Hardware, Linux, Robots
Quick update, during my evenings I’ve been working with one of the Raspberry Pi’s I won on a local contest a few months ago, and it’s generally derailed into some kind of “let’s put as much stuff on it as possible”, meaning that I currently got my Raspberry Pi hooked up with:
- Slice of Pi
- Adafruit PWM driver
- Raspicam on a simple pitch/yaw servo gimbal that me and my 1,5 year old put together in 10 minutes. Controlled via PWM.
- MPU9150 sparkfun breakout board
- 2 Arduino Nano V3.0
The two Arduino Nanos have split functionality, where one will provide me with data that needs to be gathered frequently, and the other is used for slow processes such as reading out 1-wire temp sensors etc.
The first nano will have the following functions hooked up to it:
- 3x HC-SR04 ultrasound distance sensors
- Voltage measurement 0-20V circuit
- Control of 2 relays
- 3x line tracking sensors
- Reed switch
- 2x motor controls via L298P chip
The second nano has the following hooked up to it:
- MPX2200GP pressure sensor (will use something else soon’ish)
- 2x 1-wire DS18B20 temperature sensors.
- Others?
The general idea was to move timing critical stuff off the raspberry to the Nano and let the first one deal with quick sensor readouts, while the second Nano is dropped off with relatively slow sensors (DS18B20 takes very long time to read out for example). The two nanos will talk to the Raspberry via SPI I think, or possibly serial ports, but this is less likely as it would either require me to use one USB serial driver and the raspberry UART or get a 2 port USB hub of some kind and talk via USB UART’s.
I’ve meanwhile also played around with Eagle CAD for the first time in my life, making some electrical drawings of the hookups. I’m considering making a PCB layout of everything when I get there, not sure if there is any interest in this out there except for “the lols”. The image is still very raw and missing a lot of stuff that I know needs to be added at some point.
During christmas I spent some time making opencv haar cascade training on clementine detection and generally fooling around with it. I think I’m leaning towards making a robot (chassi on the way) which will travel around in the room looking for objects… I guess some of the sensors are a little overboard for this, but it’s all fun and games while it’s not work… 😉
1 hour Raspberry pi camera controller
Kids really chew into your spare time. I got some time the other day to have some fun with a Raspberry pi, raspicam, Adafruit pwm servo driver, 2 servos, double sided tape, tape and cardboard. In 60 minutes I managed to make the “thing” in the video. OK, some stuff was pre-assembled :-).
Also, I’ve just finished setting the construction up running on Battery power. 2x zippy compact 3300mah 4s (14,4v nominal LiPo) in parallel via a 5v 5A bec powering both the servos and the Raspberry hardware. Running everything including servos for 4 hours , my measurement is that I’ve used less than 10% of the battery capacity.
The servos are currently controlled using up, down, left and right keys and the application is just a modified example from Adafruit. However, it should be very easy to integrate with either the mpu 9150 breakout unit I’ve also installed and make a simple gimbal of sorts.
But first I’m planning to test integrating the code with the opencv haar object recognition stuff I did during the Christmas holidays, for example track clementines.