Actors not seen by LIDAR sensors

I am having an issue getting some LIDAR sensors to detect actors in a world file. I am trying to use a TIM5661 in simulation to sense a moving actor, but the sensor is completely unable to sense the actor. I can see the actor moving around in Gazebo, but the sensed data from the lidar doesn't see the actor at all. Here's the world file that I am using: model://sunmodel://ground_planemodel://bookshelfbs2 2 0 0 0 0walk.daewalk.daetrue I am launching the world with a call to gazebo_ros/empty_world.launch. I also launch state publishers to visualize the data: Finally, my model urdf is here: 0 0 0 0 0 0false152701-2.356194490192.356194490190.0510.00.06gaussian0.00.00666/scanbase_link Finally, I add the robot to the simulation with a spawn_model node: rosrun gazebo_ros spawn_model -file simple_test.urdf -x -2 -urdf -model test When I visualize the /scan topic, I can clearly see a bookshelf that is static in the world, but the actor is not visible at all. Any ideas? For reference, here's a few screenshots of gazebo and rviz: