# Revision history [back]

Thanks to ffurer, I found the problem now. I tried to have an empty base link for easier placement of the stuff. Well but actually the bumper seems to need full inertia setup in the chain from base link. Otherwise Gazebo crashes. Now I just need how to get a more "useful" topic from that contact, which can be got from a node on a real robot.

What I tried with my code above was:

CAUTION: CODE, NOT WORKING:

<link name="base_link"/><!-- PROBLEM -->
<xacro:inertia_box x="${chassis_len}" y="${chassis_width}" z="${chassis_height}" mass="1"> <origin xyz="0 0 0" rpy="0 0 0" /> </xacro:inertia_box> <visual> <geometry> <box size="${chassis_len} ${chassis_width}${chassis_height}" />
<box size="${chassis_len}${chassis_width} ${chassis_height}" /> </geometry> </collision> </link> <gazebo reference="chassis"> <material value="Gazebo/Green"/> </gazebo> <joint name="base_chassis_joint" type="fixed"> <parent link="base_link" /> <child link="chassis" /> <origin xyz="0 0${chassis_floor_clearance+chassis_height/2}" rpy="0 0 0" />