To minimize trips to the field and maximizes the use of the agency's resources, the PathRunner Collection System also utilizes up to six video images collected on digital computers to allow real-time collection and storage of high-resolution images. With single camera resolutions up to 2500 X 2000 (about twice the vertical resolution of HD television), the PathRunner collection system offers the highest quality imaging available today to be collected with all other data types in a single pass and called upon instantaneously without ever leaving your desk.
Pathway Services uses high-resolution, full frame progressive scan cameras provide at least 1300 x 1030 pixels and up to 2500 X 2000 pixels to assure crisp, clear images of the roadway under a variety of weather conditions.
The images are captured, compressed and stored in JPEG format at posted speed limits (maximum 70 MPH). Upon playback, the added resolution allows the user to zoom in on the digital images in order to see more detail of the roadway, including inventory items such as signs, ramps, guardrail, etc. The added image detail is useful for many different inventory items such as signage, bridges, shoulders and guardrails. Highly accurate distance measurements can be made easily using the grid calibrations in the playback software.
With high-resolution images comes the ability to conduct highly-accurate sign inventory collection. In the workstation environment, end-users can quickly quantify, classify and report a wide variety of roadway assets such as signage, traffic signals, guardrails, bridges, pavement type, security devices, railroads and many more. All data types are tied to linear referencing and GPS for display and callback with other collected types such as roadway imaging and state generated maps.
Using collected imaging at resolutions up to 2 times that of HD, sign inventory collection can be conducted to achieve accuracies never before seen in this industry. Configurations files can be loaded to include standard directories of signage (such as MUTCD) or custom libraries can be created to include the sign type and any other variable you wish to inventory. Using the onscreen menus and clicking on the stored image, a database is created storing the sign type, condition, dimensions and latitude/longitude information for each sign entry. This data is therefore tied to all other data and image types and can be called upon by any end user in a GIS interface when inventory is complete.
Additionally, the use of the 360-degree immersive imaging can be a valuable tool to characterize every intersection, railroad or interchange from every known direction. This imaging allows all segments of the road or intersection to be viewed simultaneously in a single, dome-shaped jpeg.
Sensor data includes the automated collection of roughness, rutting, faulting and texture using non-contact sensors connected to a data acquisition computer system. Signals from all sensors are captured, conditioned, and stored in the hard disk real-time. IRI roughness is calculated using the South Dakota method of one accelerometer and one laser height sensor on each wheel path. Each sensor is sampled based on distance traveled which is generated by a distance transducer. The profiler is manufactured based on ASTM E950 and ASTM E1926 standards. Rutting is calculated using a 1028-point laser-based transverse profile. Faulting is calculated using a 3-point laser-based height measurement system to calculate the differences on the left wheel path, right wheel path, and center of the lane. Texture is measured as the variance of the individual laser height measurements. This texture data is used to automatically identify areas of raveling or weathering.
Curvature data is collected by gyroscopes mounted inside the vehicle. These gyroscopes have a 200th of a degree resolution and are sampled at fixed distances (approximately every 5 feet). The gyroscope data is also synchronized with the images and location information and the algorithms include filtering the raw data to calculate the beginning of a curve or Point of Curvature (PC), the ending of the curve or Point of Tangency (PT), the "K" value of the curve, the length of the curve, the degree of curvature, the radius of the curve and the beginning and ending points of the curve by reference post.
As a standard service, both cracking and patching data can be reduced and reported using the collected imaging and crack detection software. The computer automatically measures the length of the distress feature and creates a distress database synchronized with the sensor data and video images. Fully customized to the need of the client and project, the Pathway Services system can be programmed with different distress measuring systems, such as the SHRP's distress manual, PAVER PCI system or client-specific definitions.