At a Glance
SSI’s scalable pavement management solution is available to system integrators, end user contractors, consultants or agencies. The SSI system starts with an inertial profiler for measuring ride quality. From there, subsystem add-ons are offered for:
- Rut depth measurement
- Full lane width transverse profile
- IMU based road geometry (including cross-slope)
- HD camera imagery (forward facing ROW, downward facing pavement images, or both).
Details on the various solutions are below. Figure 1 shows an example of a fully integrated pavement management data collection vehicle configured for multilayered data collection, data analysis, and advanced pavement management decision support.
Figure 1: Automated Pavement Management Vehicle with Mid-Mount Surface Profiling System, Roadside and Roadbed Imaging, GPS/Inertial Navigation, and Ground Penetrating Radar
Ride and Roughness
SSI’s inertial profiling systems for ride quality and localized roughness are industry leading, as verified by agency certifications and independent research. Collect data in both wheel paths simultaneously at highway speeds. Instantly output reports of ride values (IRI, MRI, RN, PRI) and exact locations of areas with localized roughness, which are include plan stationing and GPS locations. Reporting is configurable according to end user specifications; adjust the reporting interval, highlight out-of-tolerance areas, and zoom/pan along any area of the detailed pavement profile traces. Data exports are supported for use of the raw data in third party application software (e.g. ProVal, ArcGIS, Excel). For details on SSI’s inertial profiling systems
Rut depth is calculated from a fourteen foot transverse profile. The transverse profile can be collected down to four inch (101.2 mm) intervals. The rutting depths is calculated based on the elevation characteristics of the profile. The profile is split into two halves where each rut depth is identified. Whether collecting at the network or project level the operator can quickly change the rut calculation sampling interval within the SSI program. The results can be viewed within SSI Profiler along with corresponding ROW images and current location along the profile trace.
Full Lane Width Transverse Profile
The transverse profile is collected using cross-slope and infrared lasers to complete a fourteen foot profile. This profile can be collected every 4 inches (101.2mm) to show rutting, and lane drop off along with curb and gutter. SSI’s software builds the elevation cross section and identifies station, GPS coordinate, rut depth and segment properties such as IRI, MRI and localized roughness statistics.
Use the on-board gyroscopic IMU and GPS to determine radius of curvature, running grade and cross slope. Correction factors and measured offsets give an accurate cross slope independent of the host vehicle’s roll, pitch or tilt. These correction factors improve the reliability of measuring super elevated curves by eliminating the vehicle suspension response. Basic versions of the road geometry system output the raw cross slope data from the gyroscopic sensor. All outputs are in Excel or PDF format with custom templates and formats available.
Collect Mean Profile Depth (MPD) and texture readings at highway speed using a high frequency laser. Collect bursts of macro elevation data to determine MPD from a macrotexture profile. The MPD can be reported at a user defined sampling interval. The results are exported to Excel or PDF for submission.
View forward facing camera images at a user specified interval throughout the collection. Images aid in identifying problem areas on unfamiliar projects and for supervisors to view distresses back in the office. Each images is geo-tagged and matched with corresponding station, and segment ride values. Two camera resolution options are available; 1.3MP and 4.3MP. All images are saved to the computer for simple export and distribution. All camera hardware is modular and upgradable at any time with brackets mounting to existing vehicle platform.
Low Resolution Camera
Collect profile data and Right of Way (ROW) images with a dash mounted USB camera that is 1.3 megapixels. The images are tagged with GPS, stationing and ride values. All images can be viewed inside SSI Profiler along with all pertinent information about the image location. At this camera resolution prominent features can be distinguished such as signs and changes in pavement texture.
High Resolution Camera
Upgrade to a high resolution camera to collect profile images at 4.3 megapixels. This higher quality camera collects more frames per second, utilizing a USB3.0 interface. With higher frames per second and a larger image sensor, this camera option eliminates blurred pictures and can be used in lower light conditions with a high aperture lens. The images will appear in SSI Profiler after being saved to the operating Toughbook hard drive in JPEG format. With the high resolution camera the user can read street signs and view pavement distresses through the windshield.
Rear Distress Camera
Capture full lane width images at highway speeds to classify distresses. The images are captured at a resolution of 3.5 to 4 megapixels depending on the image scaling. The rear down facing camera will collect a continuous image stream that can be used to determine pavement distresses. The images can be viewed in SSI’s software or through any other image viewer that accepts JPEG format. The image dimensions can be adjusted to fit the lane width required to report. The rear camera system can be integrated with an existing SSI ROW camera or inertial system. Typically the pavement distress camera is used with a dual laser profiler system, Inertial Measurement Unit (IMU) and transverse profile system.
SSI’s Profiler 3 supports layered viewing of pavement analysis results synchronized with images and GPS. View ROW or pavement surface images with associated results for the pavement condition (IRI, rut-depth, cross slope and more). Scroll through data automatically (as with a video player) or manually toggle along images. Also zoom or pan along detailed graphs of the longitudinal or transverse profiles, again with associated pavement condition reporting. The viewer software is configurable by the end user to display such pavement attributes as desired to be viewed with the pictures. Figure 2 is an example of the viewer configured to show ROW images with associated IRI and localized roughness test results.
Figure 2: Configurable Pavement Condition Viewer. Shown to View ROW Images and Ride Quality