Target Acquisition: Human Observer Performance Studies and TARGAC Model Validation

Human target acquisition performance was studied using thermal imagery that was collected during the field trial BEST TWO, organized by NATO AC243Panel4RSG.15 in 1990. In a number of carefully controlled laboratory experiments, recognition and identification probabilities were measured for a large number of stationary and moving targets at ranges between 1 and 4 km. Target detection was not investigated. The target acquisition model TARGAC was validated by comparing its predictions with observed recognition ranges. For all trials that were used in the observer experiments, TARGAC predictions were calculated on the basis of meteorological, target, background and time information that was measured in the field. The major conclusion of the observer experiments is that the human acquisition performance depends considerably on factors such as target structure, local terrain structure, and cognitive factors. In TARGAC, these factors are not modelled. For the BEST TWO situation, the model predictions were determined solely by target size and thermal imager resolution limit.