Information about human travel behaviour is of great importance for monitoring and planning. In the Netherlands, like in other countries, travel data are collected by a national travel survey. To collect individual travel data respondents have to fill in a trip diary during one day. The disadvantage of this method of data collection is that especially the number of short trips is underestimated. Also no information is available about the routing of trips. The use of GPS (Global Positioning System) enables the collection of more objective and complete travel data. In order to collect data by GPS respondents are equipped with a portable GPS-receiver. The receiver records automatically the travel behaviour by storing the successive positions during a trip together with time and other relevant data. It is expected that with such a device the respondents are burdened less compared to the traditional ways of data collection. It is also expected that the quality of the data is higher. The processing of the data can be done completely automatically since the data are already in digital form. For specific research applications route-information is available which can be used together with Geographical Information Systems (GIS). During the pilot-project the possible applications of GPS for different modes of transport (car, walking, bicycle, public transport) were investigated. An important research question was the desired precision of the position estimates in relation to the type of research (e.g. origin-destinations of trips, routing of trips, investigation of travel times, etc.). In the pre-pilot phase a lot of interesting data was collected related to technical issues, user issues, automatic data collection and methods of analysis. These are reported in the paper. The results of the research are used to define more refined technical specifications of the equipment and to improve the instructions, data-collection and methods of analysis. The improved GPS-device is applied in a follow-up project in which the use of GPS is tested on a larger scale. Preliminary results of this follow-up project are given in the paper.
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