The Visual Perception of Accelerated Motion

John Schmerler

doi:10.1068/p050167

The Visual Perception of Accelerated Motion

Perception ◽

10.1068/p050167 ◽

1976 ◽

Vol 5 (2) ◽

pp. 167-185 ◽

Cited By ~ 43

Author(s):

John Schmerler

Keyword(s):

Visual Perception ◽

Initial Velocity ◽

Stimulus Material ◽

Motion Path ◽

Accelerated Motion ◽

Acceleration And Deceleration ◽

Response Measures ◽

Event Model ◽

Short Tunnel

The present research is an investigation of how changes in the rate of motion are perceived. Five separate experiments were performed with the use of filmed stimulus material and a variety of response measures, including both categorical judgments and reproduction techniques. It was found that (a) the smaller the ratio of terminal to initial velocity, the less frequent the judgments of acceleration or deceleration, (b) deceleration was significantly easier to perceive than acceleration, (c) the perception of acceleration was facilitated when the velocity of a lead-in segment was the same as the velocity at onset of motion, (d) a short tunnel centered in the motion path facilitated the perception of acceleration and deceleration, and (e) instantaneous changes in velocity were much more easily perceived than gradual changes. A one-event model for the perception of motion change in which there is a continuous interplay between earlier, later, and interpolated motion segments is favored over a two-event model in which earlier and later segments of velocity are compared.

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Variations in Naturalistic Driving Behavior and Visual Perception at the Entrances of Short, Medium, and Long Tunnels

Journal of Advanced Transportation ◽

10.1155/2020/7630681 ◽

2020 ◽

Vol 2020 ◽

pp. 1-16

Author(s):

Xinsha Fu ◽

Shijian He ◽

Jintao Du ◽

Xiaofei Wang ◽

Ting Ge

Keyword(s):

Visual Perception ◽

Traffic Accident ◽

Driving Behavior ◽

Accident Risk ◽

Saccade Amplitude ◽

Driver Performance ◽

General Variation ◽

Naturalistic Driving ◽

Short Tunnel ◽

Correlation Factors

Driver behavior and visual perception are very important factors in the management of traffic accident risk at tunnel entrances. This study was undertaken to analyze the differences in driving behavior and visual perception at the entrances of three types of tunnels, namely, short, medium-length, and long tunnels, under naturalistic driving conditions. Using three driving behavior indicators (speed, deceleration, and position) and two visual perception indicators (fixation and saccade), the driving performance of twenty drivers at six tunnels (two tunnels per condition) was comparatively analyzed. The results revealed that the speed maintained by the drivers prior to deceleration with braking under the short-tunnel condition was significantly larger than that under the medium- and long-tunnel conditions and that the drivers had a greater average and maximum deceleration rates under the short-tunnel condition. A similar general variation of driver visual perception appeared under the respective tunnel conditions, with the number of fixations gradually increasing and the maximum saccade amplitude gradually decreasing as the drivers approached the tunnel portal. However, the variation occurred approximately 60 m earlier under the short-tunnel condition than under the medium- and long-tunnel conditions. Interactive correlations between driving behavior and visual perception under the three conditions were established. The commencement of active deceleration was significantly associated (with correlation factors of 0.80, 0.77, and 0.79 under short-, medium-, and long-tunnel conditions, respectively) with the point at which the driver saccade amplitude fell below 10 degrees for more than 3 s. The results of this study add to the sum of knowledge of differential driver performance at the entrances of tunnels of different lengths.

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Free Damped Vibrations of Rocking Rigid Blocks as Uniformly Accelerated Motions

International Journal of Structural Stability and Dynamics ◽

10.1142/s0219455417500584 ◽

2017 ◽

Vol 17 (06) ◽

pp. 1750058 ◽

Cited By ~ 13

Author(s):

Claudia Casapulla ◽

Alessandra Maione

Keyword(s):

Standard Model ◽

Initial Velocity ◽

Ad Hoc ◽

Rotational Velocity ◽

Rigid Block ◽

Constant Acceleration ◽

Accelerated Motion ◽

The Standard Model ◽

Rocking Motion ◽

Rigid Plane

This paper introduces a novel formulation for the free rocking motion of a rigid block supported on a rigid plane. The equation of the motion between two subsequent impacts is expressed as a uniformly accelerated motion only depending on the assigned initial velocity. The constant acceleration is derived by an ad hoc approximation in order to fit the results of the standard model of Housner [B. Seismol. Soc. Am, 53(2) (1963) 403–417], which is herein revisited and explored. An extensive comparison between the standard and the proposed models is carried out in terms of moment-rotation relationship, critical rotational velocity, normalized amplitude and duration of the half-cycles.

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Construction and updating of event models in auditory event processing

10.31219/osf.io/dcybu ◽

2017 ◽

Author(s):

Markus Huff ◽

Annika Maurer ◽

Irina Rebecca Brich ◽

Anne Pagenkopf ◽

Florian Wickelmaier ◽

...

Keyword(s):

Recognition Performance ◽

Sensory Information ◽

Stimulus Material ◽

Event Processing ◽

Incremental Updating ◽

Retrieval Processes ◽

Continuous Stream ◽

Event Model ◽

Event Models ◽

Event Boundary

Humans segment the continuous stream of sensory information into distinct events at points of change. Between two events, humans perceive an event boundary. Present theories propose changes in the sensory information to trigger updating processes of the present event model. Increased encoding effort finally leads to a memory benefit at event boundaries. Evidence from reading time studies (increased reading times with increasing amount of change) suggest that updating of event models is incremental. We present results from five experiments that studied event processing (including memory formation processes and reading times) using an audio drama as well as a transcript thereof as stimulus material. Experiments 1a and 1b replicated the event boundary advantage effect for memory. In contrast to recent evidence from studies using visual stimulus material, Experiments 2a and 2b found no support for incremental updating with normally sighted and blind participants for recognition memory. In Experiment 3, we replicated Experiment 2a using a written transcript of the audio drama as stimulus material allowing us to disentangle encoding and retrieval processes. Our results indicate incremental updating processes at encoding (as measured with reading times). At the same time, we again found recognition performance to be unaffected by the amount of change. We discuss these findings in the light of current event cognition theories.

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