According to Renishaw plc, laser scanning is not only used in land surveying but is being adopted in more and more industries, since it gives detailed, accurate data, very quickly, and with fewer manpower requirements, saving companies costs. Surveying is important and most of us depend on it so as to ensure order in the physical world around us.
Surveyors play an integral role in land development, from the planning and design of land subdivisions through to the final construction of roads, utilities and landscaping. Surveyors are the first people on any construction site, measuring and mapping the land. These primary measurements are then used by architects to understand and make the most of the unique landscape when designing and engineers to plan structures accurately and safely, ensuring buildings not only fit with the landscape but are able to be constructed.
According to Haglöf Sweden AB, It is valuable for everyone to keep track of assets to maintain control and healthy growth. Standardization, calibration and control systems are used in all industries, and when measuring, storing and processing data on-site, error sources are efficiently minimized. Problem areas are detected in time and actions are based on facts and figures.
It is necessary to mark the boundaries on the ground, so that they are clear to observers standing on or near the property. Also surveying and land surveying is intended to provide the evidence needed by the title insurer to delete certain standard exceptions to coverage and thereby provide “extended coverage” against off-record title matters including matters that would be revealed by an accurate survey.
Many properties have considerable problems in regard to improper bounding, miscalculations in past surveys, titles, easements, and wildlife crossings. Also many properties are created from multiple divisions of a larger piece over the course of years, and with every additional division the risk of miscalculation increases. The result can be abutting properties not coinciding with adjacent parcels, resulting in gaps and overlaps.
Many times a surveyor must solve a puzzle using pieces that do not exactly fit together. In these cases, the solution is based upon the surveyor’s research and interpretation, along with established procedures for resolving discrepancies. This essentially is a process of continual error correction and update, where official recordation documents countermand the previous and sometime erroneous survey documents recorded by older monuments and older survey methods.
GPS Surveying
The market for survey grade GNSS as well as for GIS handheld GPS is increasing in Africa. Survey grade GNSS is used by Land surveyors for new township layouts, and by construction
companies for survey control points and for staking out roads etc. It is needed for drone surveys for ground control points, and is increasingly used for precision agriculture.
According to Mr. Dave Beattie of Autobild Africa a distributor of a wide range of trusted surveying equipment from South Africa, some African countries already have CORS systems for getting accurate fixes from what is called NTrip Rovers, using cellphone networks to access the CORS bases via internet. Those that do not have such systems are looking to implement them soon.
“If I were considering purchasing I would be wary of buying a system that uses controllers and software built by the GNSS brand. This is their way of tying in customers for life. To expand ones system to several GNSS units, ones options become severely limited,” he adds.
Mr. Beattie further mentions that, to replace these controllers is very expensive. With Windows controllers and universal software one has unlimited choices and flexibility. There are universal protocols used by all brands such as RTCM or CMR+. Some manufacturers program their GNSS antennas to communicate in Brand specific protocol. Once again, these brands should be avoided because it limits one to that brand only for future purchases and expanding ones system.
“For example you may have a base and rover set and need to expand by buying another rover. Keep your options open by sticking to windows systems as mentioned above. Then support is the next big issue, and of course price. Prices can vary significantly but, unlike Opto mechanical instruments, GNSS products are all generally robust, lightweight, and give the same accuracies,” he affirms.
Coming soon : problems facing land survey in NIGERIA.
