answer: The SpiderMAV, a UAV that shoots ropes that magnetically hang on to surfaces to anchor itself in position.
The SpiderMAV is not fully operational: Once its anchors are deployed, it does not have mechanisms to remove them. However the drone concept illustrates supplemental mechanisms that may help future drones perch in position in order to save power or stabilize for jostle-free camera shots, for instance. But because of the pace of drone tech (that is still battling to apply ‘follow me’ features), it may be some time before we have seen commercial UAVs do greater than hover and fly.
Imperial College London’s Aerial Robotics Lab presented the SpiderMAV in the Intelligent Robots and Systems (IROS) conference in Vancouver a week ago. The UAV concept is really a DJI Matrice 100 drone modified with two anchor-firing systems: A “perching’ emitter on the top that utilizes compressed gas to shoot magnet-threads upward that catch until taut, spider-style, along with a “stabilizing” pod at the base that fires three anchors outward to help keep the SpiderMAV in position.