The CityFlyer project at the CCNY Robotics and Intelligent Systems Lab is using Ascending Technologies Pelican and Hummingbird Quadrotor helicopters to do research in 3D mapping and navigation. The Ascending Technologies platform provides a 1.6Ghz Intel Atom processor, 500 gram payload, GPS, and barometric altimeter. The CityFlyer add several sensors, including a Hokuyo URG-04LX and IMU. The Hokuyo URG has been modified to double as a laser height estimator. The CityFlyer project is able to combine data from these sensors to do indoor SLAM using GMapping.
The CityFlyer project has also created an RGB-D sensor by combining data from a SwissRanger 4000 and Logitech Webcam. They use this to build 3D maps for indoor environments using a 3D Multi-Volume Occupancy Grid (MVOG). Their MVOG technique is described in their RGB-D 2010 paper and more videos are here and here. Although the full sensor package exceeds the payload of the quadrotor, they anticipate that advances in RGB-D will make these techniques feasible for micro UAVs.
CCNY has released a variety of drivers, libraries and tools to support the ROS community. These include drivers and tools for the AscTec platform, libraries for dealing with aerially mounted laser rangefinders, a New College Dataset parser, and libraries for using AR tags with ROS.
CCNY has also developed a "Ground Station" application that acts as a virtual cockpit for visualizing telemetry data from an AscTec quadrotor. It is also able to overlay GPS data on an outdoor map to visualize the UAV's tracks. I Heart Robotics has a great writeup on Ground Station, and you can also checkout the documentation on ROS.org.
The ccny-ros-pkg is an excellent resource for the ROS community with complete documentation on a variety of packages, including videos that demonstrate these packages in use.
Bag files for the video above can be downloaded here (elevator_2010-08*).
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