Surveying equipment: Made to measure
By Helen Wright07 September 2011
Digital instruments speed up surveying tasks, but as the technology gets more advanced, manufacturers are also focussing on keeping them cost-effective and intuitive to operate. Helen Wright reports.
Manufacturer Leica Geosystems argues that the era of purely mechanical or optical surveying instruments is over, and digital instruments are essential for contractors to remain competitive.
It is of course still possible to work in the traditional way with a professional surveyor, but producers of digital equipment point out that this involves at least two people, requires specialist knowledge, and can take much longer.
Global navigational satellite system (GNSS) technology - GPS and similar systems like Russia's GLONASS and the proposed European Galileo network - for construction applications has also advanced rapidly over the last decade, and contractors often undertake precision surveying tasks with the help of GNSS-enabled devices.
But in order for modern technology to make it easier and quicker for contractors to take accurate measurements, the devices must be intuitive to use and also cost-effective to own.
Ensuring that GNSS technology is 'future proof' is another key concern - making sure they can receive signals like Galileo and perhaps China's Compass/Beidou information, if it becomes a global system as planned by 2020.
Manufacturers are tackling these concerns head-on. Starting with the issue of cost of ownership, Leica has launched new products aimed at contractors entering the digital surveying world for the first time, as well as packages of products that cost less than they would do to buy individually.
In June, the company launched a new entry-level laser scanner, the ScanStaion C5, targeting organisations wanting to enter into laser scanning for the first time, as well as existing customers looking for a precision machine that is cost-efficient for engineering surveys and recording 'as-built' information.
The C5 is an integrated wireless scanner with a high-resolution, colour touch screen and zoom video. It can work with standard survey accessories such as total station prisms and has been designed to be upgradable to take its functionality to the same level as Leica's most advanced C10 scanner.
Functions such as high-accuracy tilt compensation, internal digital camera access, high scan speed and long range scan can be added over time.
"From a value, productivity and data quality standpoint, the Leica ScanStation C5 is ideal for organisations wanting to get into scanning," said product manager Hans Tuexsen.
Leica Geosystems has also targeted price-conscious buyers with its Viva TS12 robotic package. The bundle of products is designed to suit daily surveying tasks, and consists of a Viva TS12 total station, Viva CS10 Controller and Leica's SmartWorx Viva software.
The combination of technology allows operators to find, lock and measure points to prisms using the total station, which can connect wirelessly to the long-range field controller.
And the onboard software has also been designed with simplicity in mind, using clear graphics, logical menu structures and non-technical terminology.
Hilti has also upgraded its portfolio with the addition of the POS18 total station, which employs touch screen technology similar to that used on smart phones.
Product manager for measuring systems, Nina Barahona, said routine measurement tasks such as setting out for excavation or foundations can be selected directed on the display, and the device guides the user step-by-step through the specified tasks.
"Distances, heights, slopes, areas and angles are calculated automatically. Planning aids are already integrated and software allows existing CAD plans to be revised and transferred directly to the total station memory via the USB interface."
Increased automation is also a central feature of Hilti's new multi-functional rotating laser, the PR 35. Well suited to precision tasks such aligning wall formwork, steel frames and facades, the device automatically aligns itself to its receiver and deviations can be constantly monitored.
This kind of intuitive operating system is a key design feature of many of the latest digital surveying devices, and their growing popularity among contractors is evidence that the industry is adapting well to the shift from manual to digital.
Topcon, for example, has landed its largest ever single order for MS05AX total stations with the sale of 105 instruments to contractor Morgan Sindall, which is constructing the Crossrail rail link in London, UK.
The MS-AX total station series are now fitted with Matrix Detection technology - a time-saving feature for setting up complex arrays of prisms for monitoring systems.
Using algorithms and high accuracy imaging sensors, MS-AX total stations are able to detect and measure all established prisms, even in low light conditions.
Engineering survey manager at Morgan Sindall, Alastair Cruickshank, said the company had been impressed by the reliability and performance of the total stations.
"The instrument always locks on to the correct prism while monitoring the buildings and tunnels of London, this is important as there are often several prisms in the field of view of the instrument, particularly in the challenging linear tunnel environments.
"The Matrix Detection function has also saved us a lot of time and hassle, we can install new monitoring prisms and the instrument just finds them automatically," he said.
The transfer of data between office and site is another important area that manufacturers in the surveying sector are focusing on. Trimble, for example, has launched a new device, the TSC3, aimed at providing more connectivity and control on site.
The TSC3 is a handheld controller featuring built-in GPS, 3G, Bluetooth, Wi-Fi and a five megapixel digital camera. Trimble said that integrating communication technology in this way can help keep real-time data flowing between field instruments and job crews as well as providing instant connections between the office and clients.
In addition, Trimble said the TSC3 can be used for both standalone navigation and measurement purposes and can also be connected with other Trimble site positioning systems, GNSS or total stations.
"These advanced capabilities and communications incorporated into one handheld device allow contractors to realise significant savings by eliminating the time and cost of physically driving data updates to and from the field," the company said.
The controller is designed to allow operators to locate, measure and record information anywhere on a construction site using one device. It has a 4.2 in (107 mm), sunlight-readable touch screen display that is shock, dust and water resistant.
Indeed, the casing of digital surveying equipment is a crucial design aspect - a device which breaks as soon as it's dropped or banged will not last long on a construction site.
Topcon Europe Positioning gave a lot of thought to making its latest GR-5 GNSS hand-held receiver as robust and rugged as possible to ensure its longevity for construction users - after all, sites can be hard on sensitive instruments..
The new model updates the GR-3 version, and is said to be able to withstand a 2 m drop onto concrete.
The GR-5 also offers increased accuracy through improved satellite signal reception - the device can access 216 universal channels and is capable of tracking multiple constellations - not just GPS, for example - and is described by the company as "guaranteed to pay dividends into the foreseeable future."
The software for Ashtech's ProMark100 and ProMark200 GNSS receivers also avoids any unnecessarily complicated features.
The ProMark 100 is a surveying tool that can record and process raw data including rover and base configurations, static or kinematic surveys or stake outs, as well as precision Real Time Kinematic (RTK) jobs and network connection settings.
The ProMark200, meanwhile, features the company's Fast Survey field software, which includes topographic features and local coordinate system support.
The device can also be used with a wide range of survey instruments to run complete survey jobs, including site calibration, stake out, and survey projects where total stations are used.
The receiver quality in GNSS-enabled equipment has improved over the last decade, and it is common for the latest devices to be able to quickly establish positions in increasingly remote locations.
It is a common claim across the board for new GNSS equipment to offer more reliable satellite signal reception, and most claim to be 'future proof' - i.e. they will be compatible with satellite signals that are yet to go into service.
These include new satellite constellations such as the European Galileo network and the Chinese Compass/Beidou navigation system, together with ongoing upgrades to the existing Russian GLONASS and US GPS constellations - developments which are expected to boost GNSS signal coverage around the world in the coming years.
Topcon Europe senior sales and marketing manager Ulrich Hermanski said there were not many other technologies in existence that were as universally applicable as GNSS.
"The sooner Galileo comes, the earlier we can tap into an even broader range of applications," he said.
Indeed, the first two satellites for the Galileo project are planned to be launched on 20 October. But launching new satellites is a hazardous business, as was demonstrated by the GLONASS project at the end of last year.
Shortly after takeoff, the rocket carrying three new satellites to augment the GLONASS constellation crashed into the Pacific Ocean, destroying its payload.
While no-one expects manufacturers of digital surveying equipment to be able to predict the future, it would seem that flexibility is key - receivers that are compatible with as many different radio, satellite and ground-based signals as possible will give users the highest long-term value for money.