Friday, November 30, 2012

The Latest and Greatest Pedestrian Research

Jacquelyn Martin / ASSOCIATED PRESS

Analysis of police collision files for pedestrian fatalities in London, 2006-10
This study analysed 197 police fatal files where a pedestrian was killed in London in the period 2006–2010, with the overall aim of providing a better understanding of how fatal pedestrian collisions in London could be prevented. The files were broadly representative of fatal pedestrian collisions in London over the period. The fatal files were coded into a database based on Haddon’s Matrix, which included items related to the environment, the pedestrian, vehicle(s) and their driver(s)/rider(s) in terms of pre-event, event and post-event. The project identified the factors or primary interventions, which if they had been in place may have prevented the collision occurring (primary prevention). Further, the project considered the causes of the injuries and where practical identified the secondary interventions, which if they had been in place may have reduced their severity. Several groups of fatalities were identified as being of special interest because of particular characteristics of the collisions. These groups generally accounted for a substantial proportion of the fatalities. In each case, the collisions within each group were analysed in terms of who was involved, the contributory factors, injuries and possible countermeasures.

Investigation of Pedestrian/Bicyclist Risk in Minnesota Roundabout Crossings
Many cities in the United States are installing roundabouts instead of traditional intersections, due to evidence that roundabouts dramatically reduce fatal and severe injury crashes compared to traditional signalized intersections. However, the impact on pedestrian safety is not clear. This project was developed to investigate pedestrian accessibility in Minnesota urban roundabouts, addressing complaints from pedestrians regarding difficulties in crossing and safety. The methodology followed in this ongoing research is typical of other observational studies. A sufficiently large number of observations on the interactions between pedestrians or bicycles (peds/bikes) and vehicles at two modern urban roundabouts in the Twin Cities of Minneapolis and St. Paul in Minnesota were collected and reduced. These observations have supported a two phased analysis. Phase 1 involved the extraction of general information describing the crossing event, such as who yielded, the location of the crossing, or the number of subjects involved. Phase 2 looked deeper into these factors by considering the conditions inside the roundabout before the vehicle proceeds to the crossing and meets with the ped/bike. The results presented, although containing no surprises, do highlight and categorize the existence of friction between pedestrians and drivers at roundabout crossings. Also the identification of factors affecting driver yield behavior and pedestrian wait time do offer good background for modeling such interactions.

Layer Object Recognition System for Pedestrian Sensing
There is a significant need to develop innovative technologies to detect pedestrians or other vulnerable road users at designated crossing locations and midblock/unexpected areas and to determine potential collisions with pedestrians. An in-vehicle pedestrian sensing system was developed to address this specific problem. The research team used stereo vision cameras and developed three key innovations, namely, the detection and recognition of multiple roadway objects; the use of multiple cues (depth, motion, shape, and appearance) to detect, track, and classify pedestrians; and the use of contextual information to reject a majority of the typical false positives that plague vision-based pedestrian detection systems. This report describes the approach and tabulates representative results of experiments conducted on multiple video sequences captured over the course of the project. The conclusion derived from these results is that the developed system is state of the art when compared to the best approaches published in literature. The false positive rates are still higher than desired for the system to be ready for commercialization. This report also provides steps that can be taken to improve the performance in this regard. A real-time system was developed and demonstrated in a test vehicle.

Active Traffic Management (ATM) applications, such as variable speed limits, queue warning systems, and dynamic ramp metering, have been shown to offer mobility and safety benefits. Yet because they differ from conventional capacity investments in terms of cost, service life, and operating requirements, how to incorporate them into the planning process is not clear. To facilitate such incorporation, this study developed guidelines for considering ATM deployments. The guidelines consist of four sets. The first set identifies required infrastructure and operational conditions, such as sensor placement and queuing behavior, to apply a particular ATM technique at a given site. The second set presents sketch planning analysis methods to estimate the operational and safety benefits of applying the particular technique at the site; these may be refined with the third set concerning a more detailed (and accurate) simulation analysis. The fourth set concerns continued monitoring of an ATM deployment at a given site. Also provided is a framework for incorporating ATM concepts into the regional planning process. The framework is illustrated with a hypothetical case study of variable speed limits implemented on I-66 in Virginia. Although Virginia metropolitan planning organizations (MPOs) and the Virginia Department of Transportation already consider operational initiatives to some degree within the planning process, a key finding of this study is that there are several ways to strengthen the inclusion of operational initiatives. These include (1) using the guidelines developed in this study; (2) linking ATM initiatives to the MPO’s Congestion Management Process; (3) facilitating the computation of operational-related performance measures such as total vehicle- hours of delay; and (4) emphasizing, when applicable, the safety and environmental aspects of ATM. The rationale for such aspects is not to promote ATM as being more effective than other types of investments but rather to compare ATM objectively with these other types of investments. For example, Appendix A illustrates how to compute a benefit-cost ratio where costs include capital and operations expenditures for the ATM and where benefits include monetized values of vehicle-hours of delay plus crash costs. In this manner, the benefit-cost ratio for an ATM project may be compared to the benefit-cost ratio for other operational or capacity projects.


  1. Wow. All that costly technical research... now can you tell us pedestrians how you expect us to safely cross the street?!