Terrestrial laser scanning also known as LiDAR (Light detecting and ranging) is becoming the preferred method for fast accurate 3D data capture.
Terrestrial LiDAR involves a laser scanner mounted on a tripod . Terrestrial LiDAR instruments are very accurate averaging around +/- 3mm per scan point for static scanning. Although some systems such as the surphaser scan achieve sub mm at 0.2mm. There a numerous terrestrial LiDAR system on the market each with their own advantages and disadvantages. When carrying out a LiDAR project it is essential that the right laser scanner is used.
The terrestrial laser scanners can broadly be defined as Phased Based or time of flight. Phase based scanners work by measuring the change of phase of the laser light. The advantage of this technology is the significant speed increase of data capture – currently up to 1,016,727 points per second.
Time-of-flight scanners emit a pulse of light which measures the amount of time it takes to travel from the scanner to the object and back , allowing the scanner to calculate the distance. The advantage of this is that data can be captured at much longer distances than phase solutions.
LiDAR Surveys can generate very large data sets made up of billions of points of data. To work with LiDAR and laser scan data specialist software is required. There are a variety of plug-ins which make it accessible in standard 3D Cad packages such as AutoCAD Civil, Architecture and Bentley micro station.
Digital Surveys provide a full LiDAR service solution and advise on all stages of your project from data capture, to post processing and delivery.