Northern Survey Flights: Subdecimetre Accuracy in Arctic Canada

Achieving Subdecimetre Accuracy in Arctic Canada

To increase capacity at Pangnirtung Airport, situated in a remote mountainous region of northern Canada, one solution could be to relocate the airport to one of two nearby sites. This article provides insight into how unmanned aerial systems were used in a preliminary engineering survey of both sites. The project achieved an accuracy of less than 10cm, despite the challenges including GNSS signal interference and difficult, rocky, rugged terrain. Even for experienced pilots, landing an aeroplane at Pangnirtung Airport on the remote Baffin Island in Canada’s Nunavut province is at best a challenge; at worst, it is impossible. The airport... (read more)

2017-03-29 10:01:57

Drowning Maldives

Rising Sea Level Threatening Island Inhabitants

Comprising 1,192 coral islands with an average height above sea level of just 1.5 metres and maximum 4 metres, the island Republic of the Maldives is dispersed across 900 kilometres of the Indian Ocean. The islands are famous for their ‘bounty': white sandy beaches, world-class snorkelling and scuba-diving facilities, and luxury holiday resorts. However, a gloomy future awaits this paradise. The Intergovernmental Panel on Climate Change (IPCC) reported that global average sea-level rose at an average rate of 1.8mm per year over the period 1961 to 2003. The rate was higher from 1993 to 2003, at... (read more)

2009-04-02 12:00:00

Complimentary Datasets for Wales

Getmapping has launched four complimentary datasets for the whole of Wales, all derived from its 2009-2010 aerial survey. The datasets include full-colour high-resolution aerial photography, colour infrared, and two height layers or elevation models. The elevation data includes a first surface, DSM, which includes everything above ground including trees, vegetation and the built environment and a bare earth, DTM, which records the rise and fall of the landscape. The 2009-2010 survey was captured using a Vexcel UltracamX digital camera mounted in a Rockwell Aerocommander. The Vexcel camera also has a built-in ‘near' or colour infrared (CIR) capability. Colour Infrared imagery... (read more)

2010-11-30 12:00:00

Indoors

Knowing where one is inside an office, shopping centre or other giant building, and how to get to where one wants to be, is key for fire fighters, medical personnel and other rescuers in a crisis situation. When a building is on fire rescuers don’t have time to study floor plans by entrance or elevators, and the receptionist will have fled to save her own life. Mobile GIS handhelds, equipped with GNSS, might provide a solution. However, on entering a building a GNSS receiver will fail to maintain tracking position. It is not the wavelength that foils GNSS signal take-up,... (read more)

2011-04-27 02:35:35

Geokosmos Conducts French Railways Lidar Survey

Geokosmos (Russia) has completed Lidar survey of French national railways in France., using combined airborne laser scanning and digital aerial photography technology. The company surveyed that part of the railroads which connects Amiens and Bouillon and covers an area of 83km. The captured data was used for producing a large-scale digital topographic map (scale 1:500) and a digital orthophoto (GSD 5cm) that will help French National Railways Service provide technical assessment of the French railways and its infrastructure. Given tough requirements set up by the customer with regards to the accuracy of captured data, aerial laser scanning combined with aerial digital photography... (read more)

2007-07-17 10:08:50

Laser Digital Theodolite with 600m Range

Sokkia Topcon releases the LDT520, a new 5" digital theodolite equipped with a telescope with laser beam emission capability. Representing a significant evolution over the previous model LDT50, the LDT520 boasts the world's longest laser range, class-topping dust and water protection, and a continuous operation time over 2.5 times that of its predecessor. Other improvements over the previous model are a better protection against dust and water (IP66), absolute encoders providing 5" angle accuracy, a longer battery life (up to 12.5 hours at maximum output) and reduction of the optical plummet to 15cm instead of 20cm of the previous... (read more)

2008-12-09 12:20:58

GNSS Handheld Data Collector

Nexteq Navigation, Canada, has announced the T5A multifunctional GNSS handheld data collector. This device is a high-accuracy GPS unit capable of 2.0cm accuracy using Real Time Kinematics (RTK) and 50cm globally using Nexteq’s i-PPP technology. The T5A combines its centimetre-level precision with a versatility allowing for accurate data collection in various weather conditions. The T5A is equipped with a 3.7” colour touch screen that is with its IP66 rating both waterproof and dustproof and includes features such as Bluetooth, Wi-Fi, digital cellular data and voice, microSD card slots and a 3.0 megapixel digital camera. Like all Nexteq Navigation GPS handhelds,... (read more)

2012-06-05 12:00:00

Correlator3D for Quebec

The Geomatics Centre of Quebec (CGQ, Canada) has completed a major mapping project using SimActive Correlator3D. The project was done in collaboration with the Nippour Group, whose responsibilities included extensive quality assurance. The project involved processing more than 2,200 scanned films at 21cm ground sampling distance (GSD) and generating digital surface / terrain models (DSM/DTM) with 1m grid post spacing. More than 350,000 ground control points were then collected through real-time kinematic GPS by Nippour, and the average vertical error of the final DTM was shown to be less than 27cm. Professionals who like to experience a live... (read more)

2011-04-27 11:33:38

NavCom Releases SF-2110M and SF-2110R Modular L1 GPS and StarFire Receivers

NavCom Technology, Inc. (CA, USA) has released the SF-2110M and SF-2110R modular L1 StarFire GPS receivers. Using StarFire NavCom's SF-2110M and SF-2110R receivers provide instantaneous 50cm accuracy. The SF-2110M utilises a compact dual-band antenna capable of receiving GPS and StarFire signals. This antenna provides phase center stability in a small, robust, lightweight format. The SF-2110R includes a separate L-Band antenna for enhanced StarFire signal reception in challenging environments and at high latitudes. Coupled with NavCom's StarFire subscription service, the SF-2110 delivers 50cm position fixes without the use of a second receiver serving as a base station. NavCom's SF-2110 series of... (read more)

2007-08-27 09:25:38

Trimble GPS Pathfinder ProXRT Receiver

Trimble has introduced the Trimble GPS Pathfinder ProXRT receiver, a versatile decimetre receiver combining dual-frequency GPS with Trimble H-Star technology, along with optional OmniSTAR and GLONASS support. In addition, the GPS Pathfinder ProXRT receiver is now capable of tracking Galileo test satellites for signal evaluation and test purposes. The GPS Pathfinder ProXRT receiver brings H-Star technology to the field in real time; just connect to a VRS network or a local base station correction source and collect decimetre (10 cm / 4 inch) or subfoot (<30 cm) positions in the field. If a VRS network or a local base... (read more)

2010-10-07 12:00:00