Footbot/Real robot information

Here you will find all the information on how to work with the footbot:

• ARGoS 2
• Aseba
• Footbot: general information
• Connecting to a footbot

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

Downloading and installing Aseba

Download Dashel:

svn co http://svn.gna.org/svn/dashel/trunk dashel

Install Dashel:

cmake .
make 
sudo make install

Download Aseba (revision 403 as revisions 404 and 405 have compilation bugs)

svn co -r 403 http://svn.gna.org/svn/aseba/trunk aseba

Check that you have QT4 install (qt4-qmake and libqt4-dev). If not, install them, then install aseba:

cmake .
make
sudo make install

Check if Aseba studio has been compiled

cd studio
./asebastudio

if asebastudio is missing it means that you don't have the necessary qt4 lib installed.

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

Put the following lines into ~/.ssh/config:

host footbot_usb
       hostname 192.168.0.202
       user root

Then, configure the interface and connect:

sudo /sbin/ifconfig usb0 192.168.0.200 netmask 255.255.255.0
ssh footbot_usb

In asebastudio, to connect use

 tcp:host=192.168.0.202;port=33333

Bluetooth

udev setup

First, you have to setup the bluetooth connection via udev. We'll use 10:00:E8:6C:F0:4D and a handbot1 as an example here, replace accordingly. You have to be root for that.

 hcitool scan

Take note of the MAC address displayed.

 cd /etc/bluetooth/
 mkdir -p passkeys
 echo -n '0000' > passkeys/10:00:E8:6C:F0:4D

Edit the file /etc/bluetooth/rfcomm.conf and add the following line:

 rfcomm1 { bind yes; device 10:00:E8:6C:F0:4D; }

Edit the file /etc/udev/rules.d/90-local.rules and add the following line:

 ACTION=="add", SUBSYSTEM=="tty", KERNEL=="rfcomm[0-9]*", WAIT_FOR_SYSFS="address", ATTR{address}=="10:00:E8:6C:F0:4D", SYMLINK+="handbot1", MODE="0666"

Create the serial connection:

 rfcomm connect /dev/rfcomm1

You should then see the device /dev/handbot1 linked to /dev/rfcomm1.

Connect with aseba

Connect with aseba using the following connection string:

 ser:device=/dev/handbot1

Connect to the IMX

Where to put the mini key on the footbots?

The connector for a connection to the IMX is "UART1" next to the IMX. The key as to be outward facing (usually it's marked white on the side for pin 1, look for the 1 on the PCB).

Connect to shell

Setup the device as described above so that the serial device /dev/footbotX exists. Then, use minicom or similar to connect to the device.

 minicom -s

Change the serial port to the device of the robot. Then select exit and press enter 2-3 times. You should see a shell.

Wifi

Works "normally" pretty reliable when used with static IPs.

In IRIDIA we have a router already configured to work with the two robots we have. When the router is on, just turn on the robots and they should connect to the wireless network by themselves. The wifi-led will first turn purple and then, after some seconds, blue. When it is blue it means that the robot is ready to communicate through wireless.

The robots have static IPs following the convention adopted in Lausanne. Each robot will thus have 192.168.1.1XX, where XX is its ID. E.g. robot number N02 will have IP 192.168.1.102. To connect to the robot via wireless first connect you pc to the "footbot" network and then do:

ssh root@192.168.1.1XX

The wireless is pretty stable when the robots are in use. However when their are idle for a while the connection tends to go down (the ssh connection become non responsive). Be aware that sometimes the blue led will stay on even after the connection has gone down. In this case, reset the IMX and everything should work fine.

Add a new robot to the network

To add a new robot connect to it via usb. Then, you have to modify the section wlan0 of the /etc/network/interfaces file in this way:

auto wlan0
iface wlan0 inet static
       address 192.168.1.1XX
       netmask 255.255.255.0
       network 192.168.1.0
       gateway 192.168.1.1
       wireless-mode managed
       wireless-essid footbot

Now get its MAC address:

ifconfig

Once you have the MAC address of interface wlan0 and you have edited the file on the robot, you can access the console of the router with your pc (192.168.1.1, user: admin, pass: admin) and add a static ip for the new robot.

After that, on the robot, just do:

ifdown wlan0
ifup wlan0

and check the connection with:

iwconfig

you can also restart the IMX board even if it is better to use the "soft" method.

You should now be able to connect to the robot with ssh.

Booting

To boot the robot, insert the battery. The boot is finished when the beacon lights up in RED->GREEN->BLUE. The flashing LED on the IMX signals a successful boot of the linux system. Beware of the sudden movement of the robot as it's booting. NEVER put it on a table when testing.

Buttons & LEDs

There are two buttons next to the selector. Press them to reset the translator and the dsPics. Usually, when there's strange stuff happening on low-level (i.e. when you have problems with aseba), press the "reset dsPics". After pressing this button, reload the backend!

The red led on the IMX next to the battery holder indicates the status of the IMX. It should be flashing. If it stops flashing, there was a kernel panic and you have to reset the IMX.

There's a reset button between the charge connector and the IMX. Press it to reset the IMX and therefore the robot, including the dsPics. This button should only be used in the rare case that the IMX/Linux hangs (red led stopped flashing).

The four green LEDs below the selector indicate aseba activity. If they stand still it means that there are no events sent, and therefore that the sensors are dead. Reset the dsPics if necessary, and reload the backend (/etc/init.d/ARGoS.sh start).

Connect with aseba

Connect with aseba with this custom destination:

tcp:host=192.168.0.202;port=33333

Does not work?

If Aseba connection doesn't work, try again without killing asebamedulla; otherwise, close Asebastudio. Restart asebamedulla, the pics and reload the backend

/etc/init.d/asebamedulla.sh restart
/etc/init.d/dspics-power.sh restart
/etc/init.d/ARGoS.sh restart

If this does not work, reset the translator and the pic per button. Rerun asebamedulla and try connecting.

If this does not work, do the same as above with setting the selector to another even value (NOT an odd one!). 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.

By script

Each package has a script that takes care of building it. You need the toolchain of course. The script is called build_real_robot.sh and should be invoked as follows:

./build_real_robot.sh footbot

There is also a top-level build script that builds the common, real robot and user package.

./build_real_robot_framework.sh footbot

By hand

Configure your environment for cross-compilation:

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

Then, compile the common package:

cd $ARGOSINSTALLDIR
cd common
mkdir -p build/footbot
cd build/footbot
cmake -DARGOS_COMPILE_REAL_FOOTBOT=1 ../..
make

If everything goes OK, compile the real robot swarmanoid common package:

cd $ARGOSINSTALLDIR
cd real_robot
mkdir -p build/swarmanoid/common
cd build/swarmanoid/common
cmake ../../../swarmanoid/common
make

If everything goes OK, compile the real robot swarmanoid footbot package:

cd $ARGOSINSTALLDIR
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 $ARGOSINSTALLDIR
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.

By script

There's a script in the $ARGOSINSTALLDIR that calls make install for all packages and then copies the libs, the backend and the controller to the specified robot via ssh. Currently it works only for the footbot. It has to be invoked as follows:

./update_real_footbot.sh <controllername> <hostname>

The controller is taken from $ARGOSINSTALLDIR/user/my_user/controllers/<controllername>.

By hand

Create a directory to install ARGoS locally:

cd $ARGOSINSTALLDIR
mkdir install

Install the common package libraries:

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

Same thing for the real robot swarmanoid common package:

cd $ARGOSINSTALLDIR
cd real_robot/build/swarmanoid/common
DESTDIR=../../../../install make install

Same thing for the real robot swarmanoid footbot package:

cd $ARGOSINSTALLDIR
cd real_robot/build/swarmanoid/footbot
DESTDIR=../../../../install make install

Now go into the install directory:

cd $ARGOSINSTALLDIR
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/

Using your controller on the real robot

So you managed to compile the controller on your pc and maybe also to update the libraries. Now what?

When you have compiled your controller you will see that in "build/controller/name_of_your_controller/" you will find and executable file. This file has to be uploaded to the real robot.

Once this is done, connect with aseba to the robot (good luck) and then you execute aseba_backend.aesl (you can find this file on the robot, under ~/ARGoS).

Now you can run your controller:

[on the robot] ./your_controller -c FILECONFIG.xml -i ID_CONTROLLOR

where FILECONFIG.xml is the same xml you used in your simulated experiments and ID_CONTROLLER is the id of your controller (really?) meaning the id that is in the xml. For example, with the "footbot_obstacle_avoidance" controller, you would execute:

./footbot_obstacle_avoidance -c obstacle_avoidance.xml -i sfc

Crashes?

After your controller crashes you have to reset the whole robot, because aseba/dashel gets into a bad state.

Using the joypad to control a footbot

If you want to test the robots with the joypad you need a program that converts the input from your joypad to events into aseba. This program is called "asebarc" and you can ask it to Manuele, Carlo or Eliseo. Once you have compiled this, connect to the robot with aseba and run "marxbot-swarmanoid-rc.aesl" (as before, ask this file to somebody). On your pc, run "asebarc" with this command:

./asebarc "tcp:host=192.168.0.202;port=33333"

You should now be able to control the footbot with the joypad.

One last thing that you have to know is that the buttons on the back of the joypad (R2 and L2, i think) are used to switch the mode of the turret between passive and rigid. The button that turns the light blue set the turret passive, while the one that turns the light green turns the turret rigid.