Equipment and Techniques

 

TOTAL STATIONS: Total Stations are the modern equivalent of the traditional Theodolite. Our Leica 1200 Robotic Total Stations combine high accuracy angle measurement with distance measurement and coded recording. This allows us to efficiently survey details in 3D and 2D either using reflector poles or using reflectorless laser technology to survey inaccessible features such as building ridge and eaves, or areas with no safe access such as live railways. Our Robotic total stations are set-up for one man operation to maximise productivity. Our high accuracy 1" total stations are used to carry out monitoring surveys to determine small movements of buildings, structures and earthworks over time for analysis.

GPS SYSTEMS GPS is a US Satellite based Global Positioning System. The technology is also known by its more modern term GNSS (which includes Russian and upcoming European and Chinese Satellites). Our GPS /GNSS Systems allow for rapid survey of large open areas and also for accurately relating site locations to Ordnance Survey Grid and Level Datum whether the site is located in built up areas or in the remotest parts of the country. GPS is the established method of determining level datum as recommended by the Ordnance Survey, and is accepted by the Environment agency for flood risk assessments. Whilst level datums can be taken from existing Benchmarks, they are often remote from sites and have not been supported, maintained or verified by the Ordnance Survey for over 10 years making them increasingly unreliable.

Our Leica 1200 GPS equipment allows efficient data collection with office based processing or with real-time co-ordinates using our Smartnet correction service in the field. GPS is typically used for long route surveys for utility pipelines, highway and railway routes and for rapidly collecting level information over large areas such as fields, beaches and landfill sites.

DIGITAL LEVELS: Anthony Brookes Surveys uses the latest Leica DNA03 digital levels for precision levelling and for high accuracy monitoring surveys. We monitor a series of reservoir dams, earthworks and structures on an ongoing basis. Digital levels use a precise barcoded staff to give reliable results to a fraction of a millimetre.

LASER SCANNERS (See Example Drawings): Laser Scanning is a relatively new technology which works by taking thousands of measurements very rapidly to build up a "cloud" of 3D points from whatever is in the instruments field of view. The points are rather like the pixels in a digital photo except that each pixel has a 3D coordinate so it is possible to view the points from any location and direction and measure precise distances between them.

It is possible to record millions of points within a few minutes which can then viewed and manipulated to produce rectified images, 2D and 3D CAD drawings and surface models. As Laser Scanning is a reflectorless technology it is particularly suitable for surveying difficult to access or hazardous areas or where access time is limited.

We have used laser scanners to survey detailed rock faces and cliffs – producing detailed CAD sections for stabilisation projects and for a series of historic structures where highly detailed elevations showing all block work and joints were produced.