Footbot/Real robot information

EPFL LSRO Wikipages

For updated info go to the EPFL wiki. http://wiki.epfl.ch/mobots-robots

Downloading ARGOS2

To download ARGoS2, you need git. First, create the file ~/.netrc with this content:

machine iridia-dev.ulb.ac.be
login YOUR_USERNAME
password YOUR_PASSWORD

and secure it:

$ chmod 600 ~/.netrc

Subsequently, configure git (once and for all) to accept Iridia dev's autosigned certificate:

$ git config --global http.sslVerify false

Finally, download the code:

$ git clone https://iridia-dev.ulb.ac.be/projects/argos2.git argos2

Connecting to a footbot

Wifi uses wpasupplicant to connect to a WPA-PSK access point. You can use USB or Bluetooth to connect to the robot otherwise. Set the selector on the robot top to an even value for USB, and uneven to Bluetooth.

USB

$ sudo /sbin/ifconfig usb0 192.168.0.200 netmask 255.255.255.0
$ ssh root@footbot_usb

footbot_usb is aliased to ip 192.168.0.202 in /etc/hosts. In asebastudio, to connect use

 tcp:host=192.168.0.202;port=33333

Bluetooth

TODO: configuration of udev for bluetooth access

In asebastudio, to connect use

 ser:device=/dev/footbotXX

Wifi

Currently unstable, check LSRO wiki.

Booting Algorithm

Beware of the sudden movement of the robot as it's booting. NEVER put it on a table when testing. If Aseba connection doesn't work, try again without killing asebamedulla; otherwise, close Asebastudio, kill asebamedulla and reset the traslator and the pic. Rerun asebamedulla and try connecting. The command to run asebamedulla is the following:

$ asebamedulla --system "ser:device=/dev/ttymxc4;fc=hard;baud=921600" 2>&1 1>/dev/null &

If this does not work, try closing Asebastudio, killing asebamedulla and setting the selector to another even value (NOT an odd one!). Reset the pic and the translator, rerun asebamedulla and try connecting again.

Battery

* full battery = 4.2V
* empty battery < 3.6V 

The charger we have at Iridia damages the batteries. We were given 12 batteries; to limit the number of damaged batteries, 10 batteries, when empty, won't be recharged. Only two batteries will be recharged.

Sensors

Camera

Cameras don't work at the same time; you can use them one by one.

If you want to stream images out of the footbot camera, in /home/root/ARGoS/bin you will find a program named mobotsvision. It is a streaming server.

To use it, the syntax is:

$ cd /home/root/ARGoS/bin
$ ./mobotsvision <omnidirectional|ceiling> <gain> <exposure>

The first argument lets you select the camera to stream images from; the gain is the amount of signal amplification you want (0-127). A low value makes the images darker, a high value makes them brighter but also much noisier. The exposure is the total amount of light allowed to fall into the CCD sensor. Its range is 0-255. A low value makes images very dark, a high value makes them very bright. The exposure is linked to the time needed to take an image; a low value entails high frame rate, a high value entails low frame rate.

When running the server, if you get an error such as:

 [FATAL] Cannot open /dev/video0: Input/output error

then try unbinding the driver and then binding it back. You do it this way:

$ echo 0-0 > /sys/bus/soc-camera/drivers/camera/unbind
$ echo 0-0 > /sys/bus/soc-camera/drivers/camera/bind

When programming a low level tool for the robot, to select the camera to use, echo to file /sys/class/gpio/gpio28/value a value of 0 for the omnidirectional camera and 1 for the front one. The camera module is mt9t031.ko.

For problems, the EPFL guy to ask is Valentin Longchamps <valentin.longchamps@epfl.ch>.

Actuators

Turret Rotation

At boot, the robot sets the 0 position of the turret. To avoid damaging the robot or having funny values, always put the gripper back in the 0 position and then switch the robot on. It can be done also when the robot is on already: set the variable 'rev.pid.enable' to 0 and rotate the turret back to its position. Then select 'Tools->Reboot->Griper-led' and the new 0 position will be set.

Framework

Compiling ARGoS for the real robot

Download and install the toolchain from http://wiki.epfl.ch/mobots-robots/toolchain . It is recommended to install it system-wide because it hasn't been tested otherwise.

Configure your environment for cross-compilation:

$ source /usr/local/angstrom/arm/environment-setup

Then, compile the common package:

$ cd /path/to/argos2
$ cd common
$ mkdir -p build/footbot
$ cd build/footbot
$ cmake -DARGOS_COMPILE_REAL_FOOTBOT=1 ../..
$ make

If everything goes OK, compile the real robot package:

$ cd /path/to/argos2
$ cd real_robot
$ mkdir -p build/swarmanoid/footbot
$ cd build/swarmanoid/footbot
$ cmake ../../../swarmanoid/footbot
$ make

If everything goes OK, compile the user package:

$ cd /path/to/argos2
$ cd user/my_user
$ mkdir -p build/footbot
$ cd build/footbot
$ cmake -DARGOS_COMPILE_REAL_FOOTBOT=1 ../..
$ make

Installing the libraries in the real robot

If you log into the robot, you'll notice a directory ARGoS. It contains the aseba backend (aseba_backend.aesl), some useful tools in bin/ and a directory lib/ in which the ARGoS libraries are stored. Whenever you fix the common or real robot packages, you have to update these libraries. To do it, the handiest way is the following.

Create a directory to install ARGoS locally:

$ cd /path/to/argos2
$ mkdir install

Install the common package libraries:

$ cd common/build/footbot
$ DESTDIR=../../../install make install

Same thing for the real robot package:

$ cd /path/to/argos2
$ cd real_robot/build/swarmanoid/footbot
$ DESTDIR=../../../../install make install

Now go into the install directory:

$ cd /path/to/argos2
$ cd install

And get into the directory where the libraries have been copied:

$ cd usr/local/lib/argos2
$ ls

Copy all the libraries onto the robot:

$ scp * root@footbot_usb:~/ARGoS/lib/