Based on some help in previous ROS questions/answers I have developed a nodelet "pipeline" that augments the pointcloud_to_laserscan package provided in turtlebot. This pipeline takes the pointcloud from "cloud_throttle.cpp" and tranforms it geometrically based on pan and tilt angles broadcast to tf using pcl_ros::transformPointCloud in a new nodelet "cloud_to_scan_tf.cpp". It then uses a third nodelet "scan_to_wide.cpp" to overlay a sequence of panned narrow scans into a wider 180 degree scan. The result is a simulation of a wider field of view, horizontal mounted, forward facing, planer laser.
The "cloud_to_scan_tf.cpp" nodelet was documented previously as "cloud_to_scanHoriz.cpp" in the "pointcloud to laserscan with transform?" ROS Answers question.
Attached below is the code for the "scan_to_wide" nodelet and a typical launch file. There is a Bool message to start/stop the panning. This nodelet sends a Float32 message to a hardware interface program to move the pan servo and receives a JointState message from the hardware interface program to indicate the pan servo position. The Kinect is tilted downwards 25 degrees to improve visibility just in front of the robot, but tf corrects the laserscan to horizontal. When the robot is moving the Kinect is stationary facing forward. When the robot stops it does a 180 degree pan, which takes about 3 seconds. The Kinect nodelets and other hardware interface programs run on a small netbook (Atom N270 1.6 GHz) at 100% CPU, but only using 20 KB/sec of wireless network bandwidth to display the laserscan on rviz on a remote desktop computer.
I'm interested if anyone has suggestions for improvement or experience integrating a panning Kinect with the navigation stack. As the FAQ suggests, a longer discussion should be moved to the mailing list.
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