When Plans Change: Task Analysis and Taxonomy of 3-D Situation Awareness Challenges of UAV Replanning

Abstract : There are a host of human factors issues involved in operating unmanned aerial vehicles (UAVs). The challenges facing UAV operators are intensified when dynamic mission environments require route replanning on-the-fly, under time pressure. The focus of this work is to characterize the specific 3-D spatial awareness challenges encountered during UAV replanning, in order to design display and automation interventions and assistance to support replanning. To elucidate these 3-D difficulties, we conducted a cognitive task analysis of the replanning problem with the Navy's VC-6 Squadron recently returned from Iraq. Key 3-D spatial challenges involved rationalizing complex combinations of avoiding airspace and terrain regions while simultaneously staying inside or near other airspace, target, and ground regions. Conventional UAV ground control displays did not support the integration or understanding of spatial aspects of the complex information necessary for UAV replanning. Replanning events were operationalized in terms of their 3-D spatial attributes and display requirements, and organized into a taxonomy pairing the events to replanning display interventions. A synthetic task abstraction of the key 3-D spatial replanning challenges was created, and experimentally validated. The display-to-event taxonomy guides future display designs, and experiment data and conventional displays serve as a baseline for future replanning displays.