NovAtel’s GPS Anti-Jam Technology (GAJT) now rides into battle and military exercises aboard the Canadian Army’s Artillery Observation Post Vehicles (OPV) that have been fitted with the GAJT‑710ML antenna.
OPVs are highly mobile vehicles that perform observation, reconnaissance and patrolling missions, surveying and acquiring strategic targets and relaying instant, accurate target coordinates acquisition to artillery fire command systems. With their exposed position on the frontlines of the battlefield, OPVs can encounter severe GPS jamming aimed at crippling their capabilities. OPVs require reliable Position, Navigation and Timing (PNT) not only to safely and effectively navigate on the battlefield, but to provide reliable information to artillery in the rear.
GAJT provides protection for GPS navigation and precise timing receivers from intentional jamming in electronic attacks, ensuring that the satellite signals necessary to compute position and time are always available.
“GAJT allows us to have confidence that the position information from the GPS constellation is assured.” said Major Mike Moulton, the project manager in the Directorate of Land Communication Systems Program Management.
NovAtel’s GAJT is a retrofittable system. A military-off-the-shelf (MOTS) product, it comes in versions suitable for land or sea applications and smaller platforms such as unmanned aerial vehicles (UAVs). The antenna works with an array of military and civil receivers, including the Army’s handheld Defense Advanced GPS Receiver (DAGR), other military receivers using SAASM and M-Code, and with civil receivers.
“GAJT scrubs off unwanted signals. It differentiates between what we can recognize as a signal coming from a satellite and something anomalous, which could be interference or deliberate jamming,” explained Peter Soar, NovAtel’s Business Development Manager for defence. “GAJT does not contain a GPS receiver, but works with the receiver that’s already installed. So GAJT faithfully passes the good satellite signals to the receiver which then operates functions such as integrity monitoring in its normal way. GAJT is in use operationally and has been shipped to 16 allied nations around the globe.”
GAJT is a null-forming antenna system that ensures that satellite signals necessary to compute position and time remain available. There is no need to replace the GPS receiver that’s already installed, as GAJT works with both civil and military receivers operating in the GPS L1 and L2 bands. It is ready for M-Code, is a non-ITAR product and is readily available to authorized customers.
Trials with the Canadian Army’s testing unit validated the technology, maintaining access to the GPS signal in an adverse signal environment. It also gave NovAtel engineers a detailed unclassified report on the trial findings and recommendations. The feedback helped NovAtel modify GAJT into a stronger product. The GAJT-710ML antennas were delivered earlier this year, and the Army worked with General Dynamics Missions Systems Canada, the prime contractor for the mission systems on the OPV, to integrate the antenna aboard the vehicle.
“GAJT is a Canadian success story. It is 100 percent produced in Canada and sourced from Canadian components. I think that the Directorate of Land Communication Systems Program Management have shown there is excellent technology in Canada that can be leveraged to meet the Army’s requirements in a very rapid manner,” added Moulton.
This story uses some quotes that first appeared in “Out of a Jam,” an article by Chris Thatcher in Canadian Army Today.
http://www.GIM-INTERNATIONAL.com Jueves 22 de Noviembre del 2018
Forest management planning is a delicate process. Environmental, economic and social aspects need to be taken into account in order to achieve sustainable development. In Quebec, before a plan can be implemented, local communities have to be consulted for their feedback and concerns. Instead of just expecting citizens to decipher complex maps, this project is aimed at sharing a realistic view of the potential changes through a 3D virtual experience. This application is based on GIS data that consists of a shapefile with information derived from a Lidar survey, as well as a digital elevation model.
In the province of Quebec, Canada, the Ministry of Forests, Wildlife and Parks (MFFP) is in charge of the sustainable development of the forests. As part of its duties, the MFFP devises forest management plans. The initial plan has to be submitted for public consultation with the local population before any action can be taken. By holding such meetings, the ministry strives to keep the public informed, while taking into account citizens’ interests and opinions. In what is commonly known as the ‘harmonisation process’, the MFFP takes the feedback into consideration and, if possible, adjusts the forest management plan accordingly.
A communication problem
However commendable this process may be, it does not always make it easy for citizens to form an opinion. Using the current technology, it is hard to visualise the real impact of the forest harvesting plans. This presents a communication problem for the forestry experts who are responsible for conveying the information to the residents taking part in the consultations. For example, maps offering an aerial perspective of the territory are currently being used to illustrate the various forestry operations. These maps are difficult to understand for anyone who is not familiar with this field of expertise. As such, for the vast majority of the population, these documents are not particularly helpful when it comes to visualising the final result in a practical manner – and yet how the end result will look matters immensely to many attendees of the consultation meetings.
A virtual solution
In an attempt to provide an answer to this communication issue, FPInnovations and the Centre en Imagerie Numérique et Médias Interactifs (CIMMI) joined forces to develop a virtual reality application called the Virtual Forest. An immersive and concrete way of visualising the result of forestry operations on a territory was created in the space of just two months. The application depicts a precise representation of the forest: each tree is in the right place and is the right height. The generation of the forest tree-type (or ‘essence’) diversity follows a precise set of rules which has been configured to represent the forestry management plan presented to the public as accurately as possible.
Instead of relying entirely on confusing 2D maps and written documents, the residents can now explore an immersive and accurate three-dimensional (3D) environment in which they can navigate at will thanks to teleportation mechanics. From a user’s point of view, the app showcases two major features: 1) it shows the before and after state of the forest (allowing the user to switch from one state to the other), and 2) it can be experienced in either a first-person or a top-down perspective. Consequently, for the population of an area targeted for a forestry operation, the Virtual Forest app provides a great tool to observe how it will visually affect their region. The intention is for the application, along with the forestry management plans and documents, to be available to the public during the consultation process. Although the Virtual Forest app is still a prototype for now, ramping it up to an operational app is not an insurmountable challenge.
From GIS data to 3D models
Geospatial data is at the root of the Virtual Forest’s creation. In this case, the dataset available was:
a shapefile showing the height and location of each tree in the area extracted from a Lidar survey
a digital elevation model (DEM) of the terrain in Esri ASCII raster format with each cell value representing the elevation.
The main objective was to represent these geospatial datasets in a realistic way in virtual reality, using the game engine Unity.
Starting with the DEM, a point was created at the centre of each cell with an elevation attribute. Using Blender’s plugin BlenderGIS, those points were imported and a Delaunay triangulation process was applied to create faces between the points. Once that was done, the resulting surface was exported in the Unity-friendly FBX format.
As for the trees, the initial shapefile was converted into CSV format. Then, a Unity plugin was built to read the file and, for each line, instantiate a 3D model of a tree at the right location. Those 3D models could then be scaled according to the corresponding height in the CSV file. The Unity plugin can take into account many types of trees, as well as the percentage of each of them on the terrain. The information available for the area was that the tallest 70% of the trees were white pines and the remaining 30% were broadleaves. In this scene, a lake and a forest road were drawn manually for visual purposes, but the process could have been implemented to add them from geospatial data as well. Also, all the steps could be fully scripted and automated, providing that the input comes in a standardised format.
The main objective was for the app to be easily usable by anybody without extensive tutorials or prior gaming experience. Indeed, the application was showcased multiple times to diverse audiences and their feedback helped to provide an understanding of how people relate to their environment and how small details can make a huge difference. For example, when foresters tested the app, two users argued that the tree type depicted in the area was not a white pine as it was supposed to be, but some kind of oak. The 3D model used correctly showed the forest essence, but one user explained that the dead leaves on the ground did not correspond to what is commonly found in a pine forest. This misunderstanding arose from the fact that the ground texture used was completely unrelated to the type of forest. People’s perspectives are clearly affected by their personal background; the developers focused on trees and models, while the foresters looked at the forest as a whole. In light of this experience, one should also expect local citizens to look for familiar features to orient themselves, such as the right texture on the ground or landmarks such as a pier, a small cabin, some huge boulders, etc.
User feedback led to many improvements to the app. The texture on the ground was added, then the sun in the sky casting shadows accurately. People in general seemed to prefer a realistic approach and attention to small details. But even after some flowers and grass had been added to the environment, something still felt static and unrealistic. To bring things to life even more, the branches were made to sway softly as if in a breeze and an audio track reinforced the immersive feeling. In 3D applications such as this, it is important to keep enhancing the realism until it becomes almost the same as the real world. Everyone should be able to relate to the environment immediately in order to focus on discussing the main issue: the planned forestry operations.
Building a virtual forest puts geospatial data to use at a human scale. Replacing unclear 2D maps with an immersive and intuitive 3D virtual reality application might become an important part of the public consultation process in the future. The next step of this project could be to define the metrics to measure the efficiency of the virtual reality application compared to the current way of conducting public consultations. This would reveal the extent to which virtual reality can improve communication between the MFFP and the people using the forest.
Consultation on integrated forest management plans:
NATO conducted its largest military exercise since the Cold War in the frigid waters and icy mountains of Norway Oct. 25-Nov. 7.
During the final days of the Trident Juncture exercise, GPS signals guiding ships, aircraft, tanks, trucks and troops began to fail. Tracking screens flickered and positions were suddenly wrong from a few meters to hundreds of kilometers.
Civilian airliners, cars, trucks, cargo ships and smartphones operating in and around Norway and Finland experienced similar disruptions. Norway-based airline Wideroe told The Barents Observer that its pilots were reporting the loss of GPS signals when flying to airports in northern Norway and Finland. Airfields affected ranged from Kirkenes, on Norway’s border with Russia, to Lyngen in Troms, much further west.
The difficulties of undertaking geospatial surveys, particularly within unstable buildings or underground environments, are well documented. However, the pressure to collect accurate, real-time data within strict timelines has certainly intensified in recent years. With increasingly tight deadlines coupled with strict budgets, conducting surveys of hard-to-access sites can be a real challenge for engineering and construction firms. In this article, Stuart Cadge from indoor mobile mapping specialist GeoSLAM explains how new innovations in building information modelling (BIM) are providing an answer with the aid of simultaneous localisation and mapping (SLAM) technology.
As engineering and construction firms grapple with issues such as skills shortages, robust safety regulations and fierce competition for contracts, traditional survey methods are increasingly coming under pressure to provide scan data which is accurate and turned around as quickly as possible. Added to this, many project managers cannot afford to solely rely on highly skilled operators to collect data if they would then need to spend multiple days processing it. Such lengthy process times often mean that operators run the risk of missing key information about the integrity of a structure.
Growing demand for BIM
This need for greater operational efficiency is one of the reasons why demand for building information modelling (BIM) technology is growing so rapidly. Site teams can now test and optimise processes at every point of an asset’s lifecycle via a dynamic ‘digital twin’, enabling them to identify potential issues such as unstable ground, existing utilities or, occasionally, historic remains that could unexpectedly halt work and push up the costs. Whatever the nature of the project, firms can ensure that any changes to building plans are digitally communicated to stakeholders wherever they are in the world, in real time. Fuelling some of the latest innovations in BIM are developments in high-definition 3D laser scanning technology, which enables operatives to produce digital representations of a building or asset while reducing the need for anyone to access hard-to-reach and/or dangerous parts of the site.
Advances in mobile scanning
Static scanning has certainly helped to improve the accuracy of site data, especially compared to manual tools like tape measures and total stations, yet it can be costly and time consuming compared to the recent technological innovations. Static surveys still require expert operators, and it takes hours – and often days – to process the data. Subsequently, without immediate access to information, decision-making is inevitably delayed and this could compromise the commercial viability of a project if deadlines are missed and costs escalate. To overcome this, project managers are increasingly deploying handheld mobile 3D laser scanning systems that empower anyone – not just surveyors – to scan a site in minutes and continually update a digital building model.
Mobile scanning is undoubtedly a great leap forward in terms of time savings and site accessibility. However, the fact that many devices rely on GPS can make them less suitable for use in tunnels, caves, mines or potentially dangerous buildings. One alternative is simultaneous localisation and mapping (SLAM) technology, which delivers the same accurate results without the need for GPS. When this is coupled with the ease of transferring to BIM, data can be captured and assessed quickly and efficiently.
How scan results are used
One application for the implementation of SLAM-based mapping can be seen in a project undertaken by Danish survey specialist LIFA, which had been tasked with measuring the leasable floor area of a 13-storey apartment block that was under construction at the time. The site team needed a solution capable of rapidly scanning the building, and so turned their attention to SLAM-based mobile mapping solutions.
According to Danish law, all leased properties must undergo an official, interior, as-built survey for property tax reasons. Using traditional techniques, this process would have taken at least two days – but the entire survey was completed in just 30 minutes by walking with the GeoSLAM ZEB-REVO on site, plus another hour for data processing. After data for all 44 apartments and communal areas had been captured, the site team created a BIM model by importing the point cloud into third-party software. Having scanned almost 5,500 square metres, the measurements using a ZEB-REVO were accurate to within a few centimetres across the entire building. Moreover, the results were well within acceptable tolerances for the tax office. The BIM model was able to display the building and had enough detail and accuracy to meet the requirements of Danish law.
LIFA is now able to measure buildings up to ten times faster using mobile scanning devices. In just six months, a two-person team mapped over 16,000 rooms in approximately 400 municipal buildings. A task like this would once have taken years to finish, rendering it commercially unviable as the processed data would have been immediately outdated. However, LIFA can now obtain the results it needs in a relatively short period of time, and apply them accordingly. Furthermore, new advancements in real-time capability are allowing for simultaneous data collection and processing, paving the way for even shorter survey times.
BIM and SLAM: What does the future hold?
All this seems light years ahead of the days when architects, surveyors and other stakeholders would manually update asset designs during the process. Instead, BIM technology enables project managers to carry out more work at the planning stage, identifying any potential issues before work begins on site. This is extremely important given that, according to industry research, a rework might amount to 12% of the total building cost. As well as speeding up construction projects, BIM also makes compliance more straightforward. For example, ISO certification can be easily shared with any stakeholder. Once the building work is complete, BIM continues to play an important role throughout the asset’s lifecycle, even if it is eventually demolished.
Speed and ease of use make handheld mobile 3D laser scanning systems an attractive choice for firms looking to remain competitive. By embracing BIM firms have significantly reduced materials waste, enabling them to offer better value for money, increase investor confidence and secure new contracts for large-scale capital projects. The fact that surveys can be completed so rapidly also means that project managers can do them more frequently, so architects, designers and facilities managers have the most up-to-date information both during the construction phase and throughout the asset’s lifecycle. As a result, scan-to-BIM, using SLAM technology, is increasingly being deployed both on large-scale projects in the construction and engineering, mining and forestry sectors and on comparatively small housing developments.
Within tightly regulated industries such as engineering and construction, the need for more frequent surveys will only grow in the coming years, as contractors are expected to deliver detailed verification and progress monitoring reports. Rather than relying on professional surveyors only, it surely makes good business sense to equip others on the team with increasingly accessible geospatial devices so they can capture new data and update the BIM representations accordingly.
Ofrecemos asesoramiento, desde una investigación preliminar, hasta la realización de un proyecto llave en mano, con la posterior colaboración en elmantenimiento y explotación, ejecutando todos los pasos intermedios. Los servicios que ofrecemos desde el nacimiento hasta la concreción de una ideason: • Identificación de proyectos • Estudios de viabilidad técnicos, socio-económicos y…Read More
Servicio técnico Especializado >
Servicio de mantenimiento y calibración de equipos topográficos Cuenta con personal especializado, con amplia experiencia enreparación, mantenimiento y verificación de equipos ópticos, mecánicos y electrónicos. Reparación de instrumentos de topografía y geomática (estaciones totales, niveles electrónicos, niveles digitales, niveles automáticos, gps, teodolitos, y otros) Contratos de mantenimiento preventivo y correctivo para…Read More
Museo de la Topografía >
Presentamos a ustedes una gran galería de imagenes e información de los diferentes equipos que han existido en este gran mundo de la topografía Read More
Mundo al instante >
La finalidad de este espacio es presentarles a uds las ultimas noticias del sector, y artículos de ingeniería que pueden ser de su interés Read More