Armed turtlebot in Gazebo

[tongtybj]

Please check README.md

[YutoUchimi]

Not working on indigo?

OK:

• Ubuntu 16.04 + kinetic
• gazebo 7.14.0-1~xenial

Error:

• Ubuntu 14.04 + indigo
• gazebo 2.2.6-1~trusty

When executing roslaunch dxl_armed_turtlebot dxl_armed_turtlebot_gazebo.launch on indigo environment, I faced the following error message.

Error [parser.cc:697] XML Element[surface], child of element[link] not defined in SDF. Ignoring.[link]
Error [parser.cc:688] Error reading element <link>
Error [parser.cc:688] Error reading element <model>
Error [parser.cc:688] Error reading element <world>
Error [parser.cc:348] Unable to read element <sdf>
Error:   Could not find the 'robot' element in the xml file
         at line 81 in /build/buildd/urdfdom-0.2.10+dfsg/urdf_parser/src/model.cpp
Error [parser_urdf.cc:2608] Unable to call parseURDF on robot model
Error [parser.cc:273] parse as old deprecated model file failed.
Error [Server.cc:300] Unable to read sdf file[/home/yuto/Projects/enshu/src/robot-programming/dxl_armed_turtlebot/worlds/empty.world]
gzserver: /usr/include/boost/thread/pthread/recursive_mutex.hpp:101: boost::recursive_mutex::~recursive_mutex(): Assertion `!pthread_mutex_destroy(&m)' failed.
Aborted
[gazebo-5] process has died [pid 18164, exit code 134, cmd /opt/ros/indigo/lib/gazebo_ros/gzserver -e ode /home/yuto/Projects/enshu/src/robot-programming/dxl_armed_turtlebot/worlds/empty.world __name:=gazebo __log:=/home/yuto/.ros/log/89a74860-df4d-11e8-b18f-b808cf4bd6aa/gazebo-5.log].
log file: /home/yuto/.ros/log/89a74860-df4d-11e8-b18f-b808cf4bd6aa/gazebo-5*.log

This error disappears when I comment out surface tag in empty.world (

robot-programming/dxl_armed_turtlebot/worlds/empty.world

Lines 326 to 333 in f5881fa

	<surface>
	<friction>
	<ode>
	<mu>0.4</mu>
	<mu2>0.4</mu2>
	</ode>
	</friction>
	</surface>

)

        <surface>
          <friction>
            <ode>
              <mu>0.4</mu>
              <mu2>0.4</mu2>
            </ode>
          </friction>
        </surface>

[tongtybj]

This is quite confusing...
There is the same description in the next model part:

robot-programming/dxl_armed_turtlebot/worlds/empty.world

Lines 369 to 376 in f5881fa

	<surface>
	<friction>
	<ode>
	<mu>0.9</mu>
	<mu2>0.9</mu2>
	</ode>
	</friction>
	</surface>

Is there any difference between these two model description?

[tongtybj]

@YutoUchimi

By the way, have you tried the gazebo samples introduced in README.md?
Please try them and confirm the expected motion.

[YutoUchimi]

Sorry, I forgot to paste the latter lines (L369-L376).
I commented out both of them (L326-L333 and L369-L376), and then it worked on indigo environment.

---

Tested on kinetic

• 1. Grasping test in gazebo via roseus
• 2. Object recognition and approaching via roseus
• 3. SLAM in Gazebo
• 4. Detect Checkerboard in Gazebo

[tongtybj]

@YutoUchimi

I found the same problem in 16.04, but it is warnning:

Warning [parser.cc:778] XML Element[surface], child of element[link] not defined in SDF. Ignoring[surface]. You may have an incorrect SDF file, or an sdformat version that doesn't support this element.
Warning [parser.cc:778] XML Element[surface], child of element[link] not defined in SDF. Ignoring[surface]. You may have an incorrect SDF file, or an sdformat version that doesn't support this element.

The reason is that <surface> should be inside the parent tag <collsion>, but not <link>.

I have fixed this bug, please check when you have time.

[YutoUchimi]

LGTM!

[tongtybj]

@k-okada

Do we need to add the instruction about how to use gazebo in the text?
e.g. copy here to the text.