Laser scanning collision investigation

TERRADAT recently untertook a trial of laser scanning for a two car collision with the help of South Wales Police.

The Topcon GLS-1000 laser scanner was used on two stations either side of the scene. The stations were referenced using the BS/OBS method (stations and one BS target were georeferenced with a total station).

A test was also carried out to investigate the use of a grey masking spray to increase the reflectance of the car body panels. Click here to view the data and photographs from the survey.

The main conclusions are as follows:

- the silver and green cars gave usable returns although low intensity
- spraying the grey masking paint significantly improved things (see
comparison images) and enabled the tyres to be scanned
- the rear bumper of the Fiat was not resolved. I think this was due
to the incident angle in relation to the scanner.
- the skid marks on the ground caused by the Fiat were mapped
- the test was very quick: we achieved two scans, and coordinated them
using a total station to enable quick registration in under 45 minutes
- the scanner also picked up surroundings within a range of around 175m which could be of interest for getting a scene overview

The data could be measured and analysed in the free Topcon Imagemaster
viewer. I will send you the project to look at in the viewer.