Laser Scanning Systems for Rail Surveying
RIEGL, based in Austria, is one of the leading providers of terrestrial, industrial, mobile, bathymetric, airborne, and UAV-based laser scanning systems for surveying. Focusing on pulsed time-of-flight laser radar technology in multiple wavelengths, RIEGL has been active in research, development and commercial production of LiDAR systems since 1978.
Worldwide sales, training, support and services are provided by RIEGL’s Austrian headquarters and its offices in Vienna and Salzburg, further main offices in the USA, Japan, China, Australia, and Canada as well as by a worldwide network of representatives.
The high value and further potential of LiDAR technology in the railway context can be explained by some of the specific characteristics: As an active – light emitting – method, LiDAR is independent from environmental light conditions and also works perfectly at night: an important advantage when it comes to surveys to be carried out at night, so as not to disturb scheduled rail traffic circulation. The capability to penetrate vegetation and capture multiple echo-signals for each emitted laser shot allows to filter the data, evaluate clearance-conflicting vegetation status and to reliably generate digital terrain models (DTM) of the area surrounding the railway infrastructure. RIEGL products are optimized for very fast data acquisition, providing dense, feature-rich data point clouds.
For the divers monitoring and surveying requests in the railway context, different scanning methods and system set-ups have been successfully used for many years: For example, terrestrial laser scanning allows high-precision local surveys, whilst mobile and airborne laser scanning is put to use for large-scale track mapping and clearance surveying. In order to meet the rail industry’s particular demands, RIEGL has designed several system solutions specifically adapted for classic rail-surveying tasks, and also provides single sensors for OEM partners and system integrators.
VMX-RAIL: Mobile Mapping System for Track Mapping and Clearance Surveying
The RIEGL VMX-RAIL mobile LiDAR Mapping System is designed with a triple scanner configuration for integration on a railcar for track mapping and clearance surveying. This rugged design of the measuring head is well suited for long-term operations even in harsh environments. The unique scanner orientation of three high-accuracy VUX-1HA laser scanners allows shadow-free coverage of the area of interest. 3 MHz pulse repetition rate and 750 lines per second result in up to 7000 pts/m2 in 3m range at 80 km/h platform speed. Perfect scanner synchronization and high frequency operation result in a regular cross pattern of scan lines in unprecedented density. This feature enhances extraction capability and reliable detection even of minute details. The system enables the capture of the complete rail corridor, including catenary systems, rail heads, and the complete periphery, even signs orthogonal to running direction. Flexible camera options allow the complementation of scan data with high resolution imaging. Open interfaces to various external sensors enable to capture optionally additional data of interest during the scanning mission. Data export to Third-Party Rail-Processing software packages is provided.
RIEGL RiCOPTER UAS LiDAR Solution for Surveying
With the VUX-1UAV LiDAR Sensor and the RiCOPTER, RIEGL offers the first complete UAS LiDAR solution from one manufacturer.
Such a UAV-based surveying system provides extremely flexible and cost-efficient operation possibilities to acquire highly accurate and informative data. Due to its agility and maneuverability of the multi-copter system, it is ideally suited for the survey of otherwise inaccessible areas or complex structures. RIEGL’s ready-to-fly remotely piloted high-performance X8 array octocopter offers 16 kg payload capacity @ 25kg MTOW with a max. flight autonomy of 30 minutes.
The RiCOPTER is equipped with the RIEGL VUX-SYS comprising the VUX-1UAV LiDAR sensor, IMU/GNSS unit, control unit and optional cameras. The system provides a 230° Field of View, an effective measurement rate of up to 350,000 measurements/sec, and a range up to several hundred meters.
Thus, the system is perfectly suitable for airborne surveying and monitoring of railway tracks and rail infrastructure, providing a dense point cloud for further processing in numerous third-party rail-processing software packages.
Further perfection of data provided can be achieved by combining both, airborne data acquisition with the RiCOPTER and mobile data acquisition with the RIEGL VMX Mobile Mapping System resulting in a comprehensive and nearly gapless point cloud of the complete scene.
RIEGL VMX-2HA Mobile Mapping System
The RIEGL VMX-2HA is a proven, fully integrated and high-speed mobile laser scanning system, including special hardware for quick and flexible mounting on railcars.
At a maximum effective measurement rate of 2 million measurements and up to 500 scan-lines per second, the mobile mapping system enables the surveying of large stretches of railway tracks at high speeds, while delivering a dense point cloud containing billions of single measurement points. The effectiveness of the system allows a surveying train to pass between two regularly scheduled trains without causing delays.
Up to 9 optional cameras (e.g. 5 MP CMOS, 12 MP CMOS, FLIR Ladybug 5+, Nikon D810) provide the corresponding georeferenced image data.
Interfaces to Third-Party Rail-Processing Software Packages are the basis for rail-specific processing of laser scan data; for example, the data is used to simulate train passages, to determine and localize clearance gauge and to conduct target-actual comparisons of track geometries.