Possible Application of GPS for Collecting Data on Travel Behaviour
DRAIJER G J A, KALFS N, Ministry of Transport (AVV), PERDOK J, MuConsult, The Netherlands
Information about human travel behaviour is of great importance for monitoring and planning. Therefore a lot of attention is paid to collecting travel data. In the Netherlands, like in many other countries, these data are collected by filling out a travel
Information about human travel behaviour is of great importance for monitoring and planning. Therefore a lot of attention is paid to collecting travel data. In the Netherlands, like in many other countries, these data are collected by filling out a travel diary. In the Dutch travel survey, called OVG, this has to be accomplished during one day by the respondents. The advantage of such a method is that it is a simple, straightforward method. The disadvantage is that it is rather imprecise, since trips can be 'forgotten' and travel ILrnes can be incorrect. In addition no information on routes becomes available.
New technologies are becoming available now which enable us to record travel behaviour automatically with the aid of GPS (Global Positioning System). Using GPS implies that respondents are equipped with a GPS receiver. These receivers automatically record the changes in positions of the respondents out of home together with time information. Such a method has advantages compared to traditional methods:
* the burden on the respondent is reduced;
* the quality of the data is increased;
* the data are stored in digital formats, facilitating the direct analysis of the data;
* more information becomes available, e.g.: - registration of the travel distance; - more precise travel times, travel velocities and route information.
The following main research questions had to be answered during the project reported here:
1. To what extent is it possible to record all travel modes (car, walking, public transport, etc.)?
2. Is the accuracy of GPS (about 50 m.) sufficient or is a higher precision of about 2 m. required (DGPS)?
3. To what extent is it possible to record data, other than the usual GPS data? This includes transport mode, trip purpose and number of passengers.
4. Which user aspects, including privacy aspects, play a role in using the GPS recording equipment?
5. Can the data be processed automatically and which problems are encountered?
The project, described in this paper is a precursor of a larger project, which is briefly described in the last section of this paper. This forerunner or prepilot phase was introduced, because there were a lot of uncertainties related to equipment design and the possibilities to record all modes. In other, related projects (e.g. Wagner and
Murakami, 1997, Zito, D'Este and Taylor, 1995) only travel by car is recorded. In another Dutch project (Roads into the future) position-information is recorded in cars and transmitted to a traffic management centre to collect floating car-data.
Although the use of GPS is successful for monitoring travel by car, there is little information available on the use of GPS for other modes. If GPS could successfully be used for recording all modes it could replace the traditional trip diaries.
The project was commissioned by the Transport Research Centre of the Ministry of Transport, Public Works and Water Management.
In this paper first a general outline and background is given in chapter 2. In chapter 3 the hard- and software is described. Chapter 4 provides an analysis of the technical and user aspects of the equipment. The outcomes of the analysed travel data are presented in chapter 5 and finally chapter 6 describes briefly the succeeding project.
Association for European Transport