An evaluation of the moving observer method of measuring traffic speeds and flows

Many attempts have been made to develop sampling techniques whereby traffic speeds and flows might be estimated at the same time by sampling a relatively small portion of the traffic stream. One such development was the moving observer technique whereby information on speeds, flows and journey times is obtained by observers in a moving vehicle in the traffic stream. This paper reports on an investigation which has been undertaken in leeds to determine the usefulness of this method under differing traffic conditions. Routes which have been studied include an urban radial route, a central city route, a ring road route and a suburban/ rural motorway route. The main conclusion drawn from the work is that the method is most applicable to peak period traffic conditions. Data for off peak and peak flow conditions are given (a).