PARTIAL CAMERA AUTOMATION IN AN UNMANNED AIR VEHICLE

The present study focused on an intelligent, semiautonomous, interface for a camera operator of a simulated unmanned air vehicle (UAV). This interface used system ''knowledge'' concerning UAV motion in order to assist a camera operator in tracking an object moving through the lan dscape below. The semiautomated system compensated for the translation s of the UAV relative to the earth. This compensation was accompanied by the appropriate joystick movements ensuring tactile (haptic) feedba ck of these system interventions, The operator had to superimpose self -initiated joystick manipulations over these system-initiated jog stic k motions in order to track the motion of a target (a driving truck) r elative to the terrain. Tracking data showed that subjects performed s ubstantially better with the active system. Apparently, the subjects h ad no difficulty in maintaining control, i.e., ''following'' the activ e stick,while superimposing self-initiated control movements over the system-interventions. Furthermore, tracking performance with an active interface was clearly superior relative to the passive system. The ma gnitude of this effect rr as equal to the effect of update-frequency ( 2-5 Hz) of the monitor image. The benefits of update frequency enhance ment and semiautomated tracking were the greatest under difficult stee ring conditions. Mental workload scores indicated that, for the diffic ult tracking-dynamics condition, both semiautomation and update freque ncy increase resulted in less experienced mental effort. For the easie r dynamics this effect was only seen for update frequency.