Per-Anders Oskarsson

Enhanced Perception and Performance by Multimodal Threat Cueing in Simulated Combat Vehicle

Objective: In a simulated combat vehicle, uni-, bi-, and trimodal cueing of direction to threat were compared with the purpose to investigate whether multisensory redundant information may enhance dynamic perception and performance. Background: Previous research has shown that multimodal display presentation can enhance perception of information and task performance. Method: Two experiments in a simulated combat vehicle were performed under the instructions to turn the vehicle toward the threat as fast and accurately as possible after threat cue onset. In Experiment 1, direction to threat was presented by four display types: visual head-down display, tactile belt, 3-D audio, and trimodal with the three displays combined. In Experiment 2, direction to threat was presented by three display types: visual head-up display (HUD)–3-D audio, tactile belt–3-D audio, and trimodal with HUD, tactile belt, and 3-D audio combined. Results: In Experiment 1, the trimodal display provided overall best performance and perception of threat direction. In Experiment 2, both the trimodal and HUD–3-D audio displays led to overall best performance, and the trimodal display provided overall the best perception of threat direction. None of the trimodal displays induced higher mental workload or secondary task interference. Conclusion: The trimodal displays provided overall enhanced perception and performance in the dynamically framed threat scenario and did not entail higher mental workload or decreased spare capacity. Application: Trimodal displays with redundant information may contribute to safer and more reliable peak performance in time-critical dynamic tasks and especially in more extreme and stressful situations with high perceptual or mental workload.

A Meta Study of Transfer of Training

A Meta study of four empirical studies of simulator training was performed. The empirical studies were performed at a battle tank simulator, a combat vehicle simulator, an active sonar anti-submarine warfare simulator, and at a simulated command and control staff exercise of an international naval mine countermeasures mission. The combined number of participants in the Meta study made use of inferential and causal statistics possible. The results showed higher ratings of motivation/fun and effect on reality than fidelity. This suggests that a simulator can provide both motivating and valuable training even if it does not have very high fidelity. The casual analysis with LISREL provided a model showing that the feeling of involvement in the simulation influences the training in the simulator, which in turn has a positive influence on the transfer of training to real world performance. Since the analysis is based on amalgamated data from different studies with partly different conditions, site specific models may be different.

Handling uni- and multimodal threat cueing with simultaneous radio calls in a combat vehicle setting

We investigated uni- and multimodal cueing of horizontally distributed threat directions in an experiment requiring each of twelve participants to turn a simulated combat vehicle towards the cued threat as quickly and accurate as possible, while identifying simultaneously presented radio call information. Four display conditions of cued threat directions were investigated; 2D visual, 3D audio, tactile, and combined cueing of 2D visual, 3D audio, and tactile. During the unimodal visual and tactile indications of threat directions an alerting mono sound also was presented. This alerting sound function was naturally present for the unimodal 3D audio and multimodal conditions, with the 3D audio simultaneously alerting for and cueing direction to the threat. The results show no differences between conditions in identification of radio call information. In contrast, the 3D audio generated greater errors in localization of threat direction compared to both 2D visual and multimodal cueing. Reaction times to threats were also slower with both the 3D audio and 2D visual compared to the tactile and the multimodal, respectively. In conclusion, the results might reflect some of the benefits in employing multimodal displays for certain operator environments and tasks.

Multimodal Threat Cueing in Simulated Combat Vehicle

We investigated three types of display combinations for threat cueing in a simulated combat vehicle. The display combinations consisted of two bimodal combinations, a visual head-up display (HUD) combined with 3D audio; a tactile torso belt combined with 3D audio; and a multimodal combination, the HUD, tactile belt, and 3D audio combined. The participants main task was to as fast as possible align the heading of the combat vehicle with the displayed direction to a threat. To increase general task difficulty and provide a secondary measure of mental workload, the participant also was required to identify radio calls. Threat localization accuracy was highest and reaction time shortest with the use of both the HUD combined with 3D audio and with the multimodal display. Subjective ratings of perception of initial threat direction were most positive for both the tactile belt combined with 3D audio and for the multimodal display. The ratings of perceived threat direction at the final phase of threat alignment, however, were most positive for the HUD combined with 3D audio and for the multimodal display. Thus, the multimodal display with HUD, tactile belt, and 3D audio combined proved to be beneficial for all measures.

Multimodal threat cueing in simulated combat vehicle with tactile information switching between threat and waypoint indication

We investigated four display configurations for threat cueing in a simulated combat vehicle. The display configurations were a tactile belt only; the tactile belt combined with 3D audio; two visual displays combined with 3D audio; and a multimodal configuration (the visual displays, the tactile belt and 3D audio combined). The tactile display was also used for navigation information. The participants main task was to drive according to the navigation information, and when threat cueing onsets occurred, as fast as possible align the heading of the combat vehicle with the displayed direction of the threat. The tactile display thus switched between navigation and treat cueing information. Performance was overall best with the multimodal display. Threat localization error was smallest with the visual and multimodal displays. The response time was somewhat longer with the tactile belt only, and especially in the front sector. This indicates interference between the two tasks, when threat cueing onsets occurred at the same position as the navigation information. This should however not be a problem in a real combat vehicle, since the sound alert will most likely not be excluded. Thus, if coded correctly tactile information may be presented for both navigation and threat cueing.

Evaluation of Tactile Drift Displays in Helicopter

Brownout during helicopter landing and takeoff is a serious problem and has caused numerous accidents. Development of displays indicating drift is one part of the solution, and since the visual modality is already saturated one possibility is to use a tactile display. The main purpose in this study was to investigate how tactile displays should be coded to maintain or increase the ability to control lateral drift. Two different tactile drift display configurations were compared, each with three different onset rates to indicate the speed of lateral drift. A visual drift display was used as control condition. The results show that best performance is obtained with the basic display with slow onset, and with complex display with constant onset rate. The results also showed that performance with the best tactile drift display configurations was equal to the already validated visual display.

Indication of Direction with Digital Map - Effects of Display Size and Time Constraints

Dismounted soldiers today use digital support for navigation and presentation of direction, and most likely such support will become standard equipment. Therefore, it is important to investigate how factors such as display size and performance time influence the ability to transform information on the map to positions in the terrain. An experiment was performed with two display sizes (3.5-inch and 9.7-inch). The participants’ task was to indicate direction to positions in the terrain represented by target symbols on a digital map with four different time limits (5s, 10s, 15s, and 20s). Participants with low spatial ability (measured by PTSOT) had lower precision with the small display, whereas participants with medium and high spatial ability performed equally well with both displays. When the time limit was shortened, task load increased, but performance was not affected. The results also confirm that important aspects of spatial ability can be discriminated by PTSOT.

Target Designation and Indication with GPS Map in Night-Op Conditions

Previous experiments have shown that target indication supported by satellite-guided positioning with map on a GPS device can be made with high precision in daylight. Since the ability of military units to operate in night-op conditions is vital, the possibilities of using such equipment with night vision goggles was tested in a night-time experiment with ten officers. Their tasks were 1) to designate direction and distance to targets visible in the terrain, and 2) to identify target positions in the terrain. They performed the tasks both with GPS device and with conventional verbal target designation. Precision was approximately equal whether the tasks were performed with the GPS device or verbally, but performance time was longer with GPS device. To elicit more information the officers also participated in focus group discussions. This provided important information on design and usage of a GPS device in night-op conditions, e.g. concerning compatibility with other systems and usability in cold weather.

Visual, Tactile, and Bimodal Presentation of Lateral Drift in Simulated Helicopter

Helicopter landing and take-off in degraded visibility caused by blowing sand or dust (brown-out) may distort the pilot’s comprehension of the helicopter’s position. This is a serious problem that may lead to unattended lateral drift or descending rate. We have previously shown advantages of redundant tactile and multimodal information a simulated combat vehicle. In order to investigate if lateral drift in a helicopter can be reduced by use of a drift display an experiment with a simulated helicopter was performed. Three types of drift displays were tested: visual, tactile, and bimodal display and compared with the primary display that did not present lateral drift. Compared with the primary display lateral drift was reduced with all three drift display configurations. This indicates the value of a drift display in the helicopter and the possibilities of disengaging the pilot’s vision for parallel tasks by the use of tactile or bimodal drift displays.

Supporting Spatial Awareness with a Hand-Held GPS-Device – Effects of Degree of Support and Light Conditions

Navigating in the terrain and at the same time keeping track other groups in the unit, enemy targets, and important terrain positions is often a hard task for dismounted soldiers, especially in night-ops conditions. To investigate if performance can be improved by GPS support an experiment was performed. A platoon navigated in the terrain and squad leaders indicated direction and distance to other squads and fixed terrain positions, both in daylight and darkness. Tasks were performed with full GPS support both for navigation and indication, with limited GPS support only for navigation, and with no GPS support. Precision of indications of direction to moving positions improved with full GPS support. To improve indication of distance with GPS support, functions that provide distance information must be used. A GPS device in combination with a night vision device can be used to support these tasks in darkness.