Choosing the right equipment for a short-term traffic count on a road segment

When determining which type of ATR equipment to use on your project, there are several options to choose from: Observation, Tube, Radar, Video, and Big Data. A little more about each type:

Observation

One of the most straightforward ways to collect traffic data on a road segment is by observing the road and keeping a tally manually. This method allows you to personally assess road conditions and identify any problems that may be causing congestion or safety hazards.

This method is ideal for short time frames on projects that require specific types of data (such as total number of cars, number of trucks, or number of lane changes). However, it can be time-consuming and doesn’t provide an extensive range of information on traffic flow.

Tube Counters

Tube counters are widely used for temporary traffic data collection. They involve rubber hoses stretched perpendicularly to the road, with the counting unit placed on the roadside. As a car passes over the tube, it creates pressure inside the hose, which triggers a sensor in the counter to register a pulse. When two or more tubes are used, modern traffic counters can concurrently analyze the data to determine a vehicle’s direction, speed, class (based on the number of axles and their spacing), gap, and headway.

The benefits of tube counters include their versatility, relative ease of installation, high accuracy, ability to collect 13-Bin FHWA classification, and relatively low cost. They are best suited for short-term data collection (one day to two weeks) where classification is important and budget is a concern.

However, there are some drawbacks. Tube counters require in-road installation in the path of traffic, which can be inconvenient and potentially dangerous. The conspicuous tubes may also alter driver behavior. Tube counters are not compatible with curvy roads, parked vehicles, or congested areas with stop-and-go traffic. They may also rip, and weather-dependent installation (rain and snow) can prohibit the tape from securing the tubes or cause water to get into the tubes, leading to malfunctions. Tube counters are limited to counting two lanes per counter, and there is a frequent need to purchase supplies (tube wear, tape, and nails).

Radar Counters

Radar counters are installed at the edge of a road and use radio waves and the doppler effect to identify moving objects by sending out a wave and collecting the reverb. Some radar counters use two parallel waves to increase accuracy and collect additional data.

Benefits of using radar counters include off-road installation, all-weather operation, classification by car length, and the ability to collect speed, gap, and headway data.

However, there are also some drawbacks. Radar counters have limited classification data, which is measured by length and not by axles. They are also not compatible with slow or stopped traffic in congested areas and curved roads. Depending on the equipment used, radar can be obstructed by parked vehicles or pedestrians.

Video Counters

Video counters involve a video camera placed above or to the side of a road segment. Recorded video is processed via software and is capable of extracting volume, classification, speed, gap, and headway data. However, these capabilities vary with specific software and camera video quality.

This method is best suited for inconspicuous data collection, on roadways with more than two lanes, in congested areas with stop-and-go traffic, areas where other data collection methods may be obstructed (by parked cars or pedestrians), road segments with slight road curves, sites where the ability to visualize traffic conditions is important, or where other methods are not suitable.

However, there are some drawbacks. Video counters require high-quality video and sophisticated software for accurate data extraction. Data processing can be labor-intensive and time-consuming. Additionally, video counters have a higher price tag compared to other data collection methods.

Big Data

Big data counts involve filtering cell phone and Bluetooth device data to isolate traffic movement. This method can analyze anything from a single road segment to several city blocks at one time.

This method is ideal for determining origin-destination traffic patterns, measuring commercial truck percentages, differentiating local from pass-through traffic, calculating average annual daily traffic, and conducting pedestrian counts. Another advantage is that this method allows you to analyze any timeframe from the past, providing instant data availability and a deeper insight into seasonal fluctuations.

However, there are some drawbacks. Big data counts may have low confidence on low-volume roads, lack standard classification data, and have a relatively high price tag.

In summary, we have presented a comprehensive comparison of various data collection methods based on different criteria. We understand that selecting the most appropriate method for your project can be a challenging task. If you require further guidance or clarification on which data collection method would be best suited for your project, please do not hesitate to reach out to us. Our team of experts is always ready to assist you in making informed decisions and ensuring the success of your project.