The Motorway Incident Detection and Automatic Signalling (MIDAS) system provides traffic data from England's motorway network via loops in each lane. This traffic data provides information on traffic conditions and is used to monitor the performance of the network and to control the traffic (eg by automatically reducing speed limits when queues are detected). It is important that the traffic data is accurate. Any inaccuracies could result in automatic traffic signals being set either unnecessarily or too late, and will lead to errors in performance statistics (eg capacities and journey times). To investigate MIDAS accuracy, a controlled test was carried out at a number of locations on the M6. Traffic data was collected from these locations using different methods of data collection (automatic traffic counters and a video survey). This report assesses the accuracy of the MIDAS traffic data on the M6 by comparison to the video survey, and also investigates whether there are any differences between various makes of data collection equipment. (Author/publisher)
Abstract