diff --git a/ros2_control_demo_description/diffbot/urdf/diffbot_description.urdf.xacro b/ros2_control_demo_description/diffbot/urdf/diffbot_description.urdf.xacro
index 03aa3497f..263be605e 100644
--- a/ros2_control_demo_description/diffbot/urdf/diffbot_description.urdf.xacro
+++ b/ros2_control_demo_description/diffbot/urdf/diffbot_description.urdf.xacro
@@ -72,9 +72,9 @@
+ ixx="${wheel_mass / 12.0 * (3*wheel_radius*wheel_radius + wheel_len*wheel_len)}" ixy="0.0" ixz="0.0"
+ iyy="${wheel_mass / 12.0 * (3*wheel_radius*wheel_radius + wheel_len*wheel_len)}" iyz="0.0"
+ izz="${wheel_mass / 2.0 * wheel_radius*wheel_radius}"/>
@@ -107,9 +107,9 @@
+ ixx="${wheel_mass / 12.0 * (3*wheel_radius*wheel_radius + wheel_len*wheel_len)}" ixy="0.0" ixz="0.0"
+ iyy="${wheel_mass / 12.0 * (3*wheel_radius*wheel_radius + wheel_len*wheel_len)}" iyz="0.0"
+ izz="${wheel_mass / 2.0 * wheel_radius*wheel_radius}"/>