Removed the / from the tf_prefix.

config/bno055_imu_sim_config.yaml

 rate: 100.0
 namespace: '/imu'
-tf_prefix: '/bno055'
+tf_prefix: 'bno055'
 imu_topic: 'imu'
 accel_offset_x: 0.08
 accel_offset_y: 0.08

config/microstrain_3dm_gx3_imu_sim_config.yaml

 rate: 100.0
 namespace: '/'
-tf_prefix: '/'
+tf_prefix: ''
 imu_topic: 'imu'
 accel_offset_x: 0.002
 accel_offset_y: 0.002

config/mpu9250_imu_sim_config.yaml

 rate: 100.0
 namespace: '/imu'
-tf_prefix: '/mpu9250'
+tf_prefix: 'mpu9250'
 imu_topic: 'imu'
 accel_offset_x: 0.06
 accel_offset_y: 0.06

launch/bno055_imu_sim.launch

@@ -23,7 +23,7 @@
            command="$(find xacro)/xacro --inorder '$(find iri_bno055_imu_description)/urdf/bno055_imu_example.xacro'" />
 
     <node pkg="robot_state_publisher" type="robot_state_publisher" name="bno055_tf_broadcaster">
-      <param name="tf_prefix" type="string" value="/bno055"/>
+      <param name="tf_prefix" type="string" value="bno055"/>
       <param name="publish_frequency" type="double" value="20.0"/>
     </node>
   

launch/microstrain_imu_sim.launch

@@ -22,7 +22,7 @@
          command="$(find xacro)/xacro --inorder '$(find iri_microstrain_imu_description)/urdf/microstrain_imu_example.xacro'" />
 
   <node pkg="robot_state_publisher" type="robot_state_publisher" name="microstrain_tf_broadcaster">
-    <param name="tf_prefix" type="string" value="/microstrain"/>
+    <param name="tf_prefix" type="string" value="microstrain"/>
     <param name="publish_frequency" type="double" value="20.0"/>
   </node>
 

launch/mpu9250_imu_sim.launch

@@ -23,7 +23,7 @@
            command="$(find xacro)/xacro --inorder '$(find iri_mpu9250_imu_description)/urdf/mpu9250_imu_example.xacro'" />
 
     <node pkg="robot_state_publisher" type="robot_state_publisher" name="mpu9250_tf_broadcaster">
-      <param name="tf_prefix" type="string" value="/mpu9250"/>
+      <param name="tf_prefix" type="string" value="mpu9250"/>
       <param name="publish_frequency" type="double" value="20.0"/>
     </node>