What frame to use when adding range_sensor_layer (sonar) to costmap
I am trying to add a sonar layer into my costmap to detect obstacles. I have used the range_sensor_layer (which is a costmap plugin) for this purpose. I have added the sonar layer parameters properly in global_costmap_params, local_costmap_params and costmap_common_params. Now, when I run Rviz, the sonar layer is not showing up. When I try to add it manually by selecting the relevant topic (/sonar), it shows an error about Frame. It says that the frame does not exist. I have seen the message from laser scan which is using frame_id : camer_depth_image. I want to know what frame_id should I use in the sonar's message which should already exist and upon which the sonar message will be broadcast. (I am new to frames in ros). Thanks