Development of a Status Display for Supervisory Control of Multiple Remotely Piloted Aircraft Operated in Controlled Airspace

Kurzfassung

In the presented study a status display for supervisory control of multiple Medium Altitude Long Endurance Remotely Piloted Aircraft Systems (MALE RPAS) operated in controlled airspace was developed. The display visualizes the functional states of all aircraft under control, enabling one remote pilot to supervise multiple RPAs simultaneously. In a first step of the development process, required functions to operate multiple RPAs in controlled airspace were identified by developing an abstraction hierarchy. Identified functions include e.g. altitude control and hydraulic supply for each aircraft. The identified functions were then allocated to the system and the remote pilot based on a supervisory control concept. The remote pilot is responsible for the supervision of the aircraft and the configuration of the system, while the system executes the identified functions. Hence, the remote pilot needs to be informed about the respective functional states. Functional states were specified as normal, caution, critical and transit. Furthermore, specific system parameters that inform about the respective functions (e.g. hydraulic pressure for hydraulic supply) were specified. In a next step, function specific icons were designed. Each icon represents a different function from the abstraction hierarchy. The icons are arranged in a matrix format. Columns represent the different RPAs under the remote pilots control; rows represent functions. A row thus consists of multiple identical icons, each representing the same function for a different aircraft. Color is used to differentiate between the functional states (e.g. grey for normal and cyan for transit). Actual values of system parameters can be obtained by opening a separate window. The developed display was embedded into the DLRs remote pilot station U-Fly and a simulation study with four pilots was conducted. The goal of the study was to gather initial data for a validation of the design concept. In a first scenario, the pilots were instructed to supervise five RPAs and execute altitude, speed and heading changes as instructed by air traffic control. In a second scenario, an engine failure occurred, leading to a critical functional state. The pilots were instructed to identify the critical system parameter. After the simulation trials, a structured interview was conducted. The interview contained detailed questions about the design concept of the status display and the design of the icons. Results indicate that the design concept was reasonable and easy to understand. Important information was quickly accessible and functional states could easily be identified. The categorization and visualization of functional states was reasonable for all subjects. Furthermore, all subjects found the design of the icons to be intuitive. The results show initial evidence that the display is suitable for supervising multiple RPAs in controlled airspace. Additional studies with more test subjects, more (critical) situations and more objective data are necessary in order to further evaluate the display and draw concrete conclusions about its usability.