Point cloud data in minutes
Dean Palmer reports on a unique 3D laser scanning device that scans 120,000 points per second to generate high quality point cloud data in minutes for CAD systems
A 3D laser scanner that can scan 120,000 points in a full 360-degree envelope and generate high quality point cloud data in a matter of minutes, has been launched recently.
Described by its developer as "computer aided measurement" device, the machine is already being utilised by several large automotive plants in the UK, to scan complete factory layouts and generate full 3D representations of machines and production equipment. According to the developer of the technology, Faro, the Laser Scanner LS was used to scan a third of Nissan Sunderland's complete factory layout in a two-week shutdown period recently. The scanner is also being used in other industries, including oil and gas, surveying, quality control, archaeological studies and forensics.
Faro's Laser Scanner LS (large scale) has a unique modular design made up of four separate component parts: a base module; PC module; laser and distance sensor module; and a mirror module. At any time, these modules can be exchanged or upgraded enabling the user to tailor the scanner to the application.
The scanner works by sending an infra-red beam into the centre of a mirror, which rotates at 40,000rpm. This deflects the laser around the environment being scanned. Upon contact the beam is then reflected back into the scanner and the 'phase shift' of the infra-red is measured giving the distance of the laser from the object. Encoders are used to measure the mirror rotation and the horizontal rotation of the laser scanner, enabling the X,Y and Z coordinates of each point to be recorded.
The advantage of phase shift technology is the speed of point capture, up to 100 times faster than 'time of flight' based technology. The scanner is also capable of recognising the luminosity of the reflected surface. This builds a grey scale image similar to a 3D black and white photograph. The addition of a colour option enables scans to be brought to life, adding to the realism of the images and in complex environments, identification of specific pipes or ducts becomes easier.
The Laser Scanner LS is linked to Faro's 'Scene' software, where settings for the scan can be altered, including resolution and scan speed. By clicking a button, the scan will begin and the captured data is displayed 'live' on screen. Once the scan is complete, the user can navigate the scan in 2D or 3D views and make basic measurements within the scan. VRML data can be imported into the point cloud to assess potential collision risks. The 'Scene' software also enables Tomography, data filtering and allows the user to export data in different CAD formats, including IGES, DXF and AutoCAD. Basic features such as pipes and planes can be recognised and several scans can be registered, enabling multiple views of a scanned environment.
There are currently around 25 to 30 Laser Scanner LS devices in operation globally. Each scanner costs around £60,000 to purchase, but Faro is offering customers an attractive leasing option, where the costs can be spread over longer term contracts.