Any brief tutorial???

[hangil2478]

Hi.

It seems that the source code is not maintained after sometime.

Could you please explain us with some examples to demonstrate how we can run the multi-robot exploration example just like shown in your video (https://www.youtube.com/watch?v=md29t2Xbdug)?

We just want to run it in virtualized world first.

Thanks.

[dkkim93]

Yes please. If there would be a tutorial or simple example how to run, it would be great!
Thank you.

[LeoSko]

For others who also want to see at least something unless maintainers respond here. Some time ago our team created a couple launch-files that at least work and can be used for a start.

The first one is just one robot in stage, which explore it by itself (here). The other most point we reached was grouping several robots manually using adhoc_communication services, where we used this file to start with.

Beware that it needs my own modification of teleop_twist_keyboard

[npapadimitriou]

Do anyone may have any .launch file for real hardware?? I use 2 turtlebot2 with indigo but their exploration is reaaally slow and I am having difficulties in understanding if I have to start more nodes that in simulation mode or if there are any parameters that I have to configure inside source files . Thanks in advance!!

[YCH188]

@LeoSko Hello,I run the
roslaunch explore explore_one.launch
but get errors
Could you help tell me what is the prolem and how to solve it? Thanks a lot!

[robot_0-4] process has died [pid 2432, exit code 1, cmd /home/ych/adhoc/multibot/adhoc_communication/build/devel/lib/adhoc_communication/adhoc_communication /robot_0/adhoc_communication/new_robot:=/adhoc_communication/new_robot /robot_0/adhoc_communication/remove_robot:=/adhoc_communication/remove_robot /robot_0/base_pose_ground_truth:=/base_pose_ground_truth /robot_0/adhoc_communication/send_frontier:=/adhoc_communication/send_frontier /robot_0/adhoc_communication/send_auction:=/adhoc_communication/send_auction __name:=robot_0 __log:=/home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4.log].
log file: /home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4*.log
[robot_0-4] restarting process
process[robot_0-4]: started with pid [2914]
socket():: Operation not permitted
[ INFO] [1546939542.503405243, 0.500000000]: Loading from pre-hydro parameter style
[ INFO] [1546939542.562599330, 0.500000000]: Using plugin "static_layer"
[ INFO] [1546939542.578536548, 0.500000000]: Requesting the map...
[robot_0-4] process has died [pid 2914, exit code 1, cmd /home/ych/adhoc/multibot/adhoc_communication/build/devel/lib/adhoc_communication/adhoc_communication /robot_0/adhoc_communication/new_robot:=/adhoc_communication/new_robot /robot_0/adhoc_communication/remove_robot:=/adhoc_communication/remove_robot /robot_0/base_pose_ground_truth:=/base_pose_ground_truth /robot_0/adhoc_communication/send_frontier:=/adhoc_communication/send_frontier /robot_0/adhoc_communication/send_auction:=/adhoc_communication/send_auction __name:=robot_0 __log:=/home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4.log].
log file: /home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4*.log
[robot_0-4] restarting process
process[robot_0-4]: started with pid [3107]
socket():: Operation not permitted

[LeoSko]

@YCH188 for sure, this is some permissions problem (socket():: Operation not permitted). It has been a long time, but I remember you should try using sudo or root user to launch packages. This is needed because adhoc_communication uses raw unix sockets that are not available for usual users.

[YCH188]

@LeoSko Thank you. Another problem is that in the launch file, the [robot_0-4] isn't started, why it says [robot_0-4] process has died.

[LeoSko]

@YCH188, is there anything in specified log file?

[YCH188]

The log are as below:
the robot_0-4 died and restart.

[robot_0-4] process has died [pid 2432, exit code 1, cmd /home/ych/adhoc/multibot/adhoc_communication/build/devel/lib/adhoc_communication/adhoc_communication /robot_0/adhoc_communication/new_robot:=/adhoc_communication/new_robot /robot_0/adhoc_communication/remove_robot:=/adhoc_communication/remove_robot /robot_0/base_pose_ground_truth:=/base_pose_ground_truth /robot_0/adhoc_communication/send_frontier:=/adhoc_communication/send_frontier /robot_0/adhoc_communication/send_auction:=/adhoc_communication/send_auction __name:=robot_0 __log:=/home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4.log].
log file: /home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4*.log
[robot_0-4] restarting process
process[robot_0-4]: started with pid [2914]

[LeoSko]

@YCH188, if this is the only content of /home/ych/.ros/log/5db71998-1327-11e9-a4f9-2c337a5bf879/robot_0-4*.log, then I suggest you to look up how to increase logLevel for components to the most verbose (TRACE probably) and see if there is something useful.

[YCH188]

@LeoSko OK, I will try. Thank you.

[Prab09]

@LeoSko Hello,
I am getting this error:
ERROR: cannot launch node of type [adhoc_communication/adhoc_communication]: can't locate node [adhoc_communication] in package [adhoc_communication]
when I launch adhoc_communication.
How do I solve this?
Thanks!

[LeoSko]

@Prab09, this is a basic error - ROS can't locate module (aka node) or package. You need to get used to ROS packages system first. Carefully read packages wiki page and complete tutorials first (Beginners №№1-5, Intermediate №1).

[Prab09]

@LeoSko alright fixed that issue. Thanks!
However, when I run the file adhoc_communication.launch, I get the following error.
prab@prab-VivoBook-ASUS:~/catkin_ws$ roslaunch adhoc_communication adhoc_communication.launch... logging to /home/prab/.ros/log/1407f2c8-697f-11e9-952e-80c5f2ca1789/roslaunch-prab-VivoBook-ASUS-9485.log
Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://prab-VivoBook-ASUS:42567/

SUMMARY

PARAMETERS

• /adhoc_communication/enable_cooperative_relaying: True
• /adhoc_communication/interface: lo
• /adhoc_communication/log_path: /home/prab/logs
• /adhoc_communication/mac:
• /adhoc_communication/max_packet_size: 10000000
• /adhoc_communication/nack_threshold: 10
• /adhoc_communication/num_e2e_retrans: 10
• /adhoc_communication/num_link_retrans: 2
• /adhoc_communication/robot_name:
• /adhoc_communication/robots_in_simulation: 10
• /adhoc_communication/sim_robot_macs:
• /adhoc_communication/simulation_mode: False
• /adhoc_communication/tx_power:
• /adhoc_communication/use_sim_time: False
• /rosdistro: kinetic
• /rosversion: 1.12.14

NODES
/
adhoc_communication (adhoc_communication/adhoc_communication)

auto-starting new master
process[master]: started with pid [9495]
ROS_MASTER_URI=http://localhost:11311

setting /run_id to 1407f2c8-697f-11e9-952e-80c5f2ca1789
process[rosout-1]: started with pid [9509]
started core service [/rosout]
process[adhoc_communication-2]: started with pid [9525]
Error for wireless request "Set Tx Power" (8B26) :
SET failed on device lo ; Operation not permitted.
[ERROR] [1556433025.021522716]: Cannot create directory "/adhoc_communication/prab-VivoBook-ASUS/".

I am also in root. Any idea how to fix this would be much appreciated. Thanks!

[LeoSko]

@Prab09, that is a tricky one. Since it was a long time ago, the only thing I remember is that username or PC's name for current computer should not contain dashes (-), this is probably the case here (who knows, why?😞).

You could also try to:

• set finer level of logs (e.g. DEBUG)
• create directory /adhoc_communication/prab-VivoBook-ASUS/ by yourself
• recompile package to add some debug output where it tries to create directory