Detection Of Collision Events Research Articles

Aging and detection of collision events on curved trajectories

In the current study we examined age-related differences in the detection of collision events on a curved trajectory. Observers were presented with displays simulating an approaching object moving at a constant speed that was either on a collision or a non-collision path. The object disappeared before reaching the observer, and the task was to determine whether the object was on a collision path. In a series of three experiments, we manipulated the motion trajectory of the object (linear or curved), time-to-contact (TTC), and radius of the curvature. We found decreased performance with older as compared to younger observers when the object was traveling on a linear trajectory at long TTC. However, there was no age-related decrement in detecting a collision when the object was traveling on a curved trajectory. These results indicate a similar ability for older and younger observers in detecting collisions on a curved trajectory.

Age-related differences in detection of collision events on linear trajectories

Age-related differences in detection of collision events on linear trajectories

Detection of collision events on curved trajectories: Optical information from invariant rate-of-bearing change

Previous research (Andersen & Kim, 2001) has shown that a linear trajectory collision event (i.e., a collision between a moving object and an observer) is specified by objects that expand and maintain a constant bearing (the object location remains constant in the visual field). In the present study, we examined the optical information for detecting a collision event when the trajectory was of constant curvature. Under these conditions, a collision event is specified by expansion of an object and a constant rate-of-bearing change. Three experiments were conducted in which trajectory curvature and display duration were varied while time to contact, speed, and initial image position of the collision objects were maintained. The results indicated that collision detection performance decreased with an increase in trajectory curvature and decreased with a decrease in display duration, especially for highly curved trajectories. In Experiment 3, we found that the presentation of a constant rate-of-bearing change in noncollision stimuli resulted in an increase in the false alarm rate. These results demonstrate that observers can detect collision events on curved trajectories and that observers utilize bearing change information.

Aging and the detection of observer and moving object collisions.

The authors examined age-related differences in the detection of collision events. Older and younger observers were presented with displays simulating approaching objects that would either collide or pass by the observer. In 4 experiments, the authors found that older observers, as compared with younger observers, had less sensitivity in detecting collisions with an increase in speed, at shorter display durations, and with longer time-to-contact conditions. Older observers also had greater difficulty when the scenario simulated observer motion, suggesting that older observers have difficulty discriminating object motion expansion from background expansion from observer motion. The results of these studies support the expansion sensitivity hypothesis-that age-related decrements in detecting collision events involving moving objects are the result of a decreased sensitivity to recover expansion information.

Perceptual information and attentional constraints in visual search of collision events.

This study examined the detection of collision events when multiple moving objects were present in the scene. Observers were presented with displays simulating a 3-D environment with multiple moving objects. The authors examined the ability of observers to detect collisions using a signal-detection paradigm and a visual search paradigm. The results indicated that, overall, observers were quite accurate at detecting collisions. Observers used both expansion information and static position to detect collisions, with expansion information being the more important source. Singleton search conditions were not processed in parallel, and conjunction search conditions had poorer performance than singleton search conditions. In addition, reaction times were greater for target-present trials as compared with target-absent trials. The results are interpreted in terms of 4 visual search hypotheses for collision detection when multiple moving objects are present.

Visual Search and the Detection of Collision Events during Driving

In the present study we examined the accuracy of observers in detecting collision events. Observers were presented with displays simulating a 3D environment with multiple moving objects. We used a signal detection paradigm to determine the ability of observers to detect a collision event when multiple moving objects were present. We also examined whether the task can be performed in parallel or requires attention. The results showed that observers' sensitivity decreased with an increase in the number of distracter objects moving in the scene, suggesting that observers were performing a visual search to determine whether a collision target was present in the display. This finding indicates that collision detection when multiple-moving objects are present is not processed in parallel. In addition, the results indicated that sensitivity increased with an increase in display duration. This suggests that as the collision event became more imminent detection performance increased.

Speed, size, and edge-rate information for the detection of collision events.

In the present study an alternative analysis to tau was considered that was based on perceived speed and size and that assumed constant deceleration for the detection of collision events. Observers were presented with displays simulating a 3-D environment with obstacles in the path of observer motion. During the trial, observer motion decelerated at a constant rate and was followed by a blackout prior to the end of the display. Observers had to detect which trials resulted in a collision. The results indicate that collision detection varied as a function of the size of the obstacles, observer speed, and edge rate--findings not predicted by an analysis of tau. The results suggest that observers use an analysis based on speed and size information. A model that assumes constant deceleration is proposed for braking control.