Trimble has awarded a significant in-kind gift to the Department of Construction Management at Colorado State University (CSU) that will expand the university’s leadership in training and research for 3D building design, construction management, digital fabrication, civil infrastructure, geomatics and the sustainable built environment.
The gift will enable CSU to integrate across its curricula Trimble solutions that are rapidly transforming how building and living environments are designed and constructed.
Trimble’s portfolio of building construction solutions support the Constructible Process, Trimble’s approach for enabling digital transformation of architecture, engineering and construction (AEC) workflows. This process empowers disparate teams across the construction lifecycle with actionable data to improve productivity and reduce waste.
The gift will be recognized as “Technologies by Trimble” throughout the Department of Construction Management.
Photo: Trimble
The department’s labs will include Trimble laser scanning, Trimble Field Link and Rapid Positioning Systems, UAS and surveying systems, and GNSS receivers. Trimble’s software packages will include RealWorks scanning software, Trimble Business Center, Vico Office Suite, Tekla Structures, Sefaira Architecture and its 3D modeling software SketchUp Pro, along with MEP software such as AutoBid SheetMetal and Mechanical, Sysque and AccuBid Electrical estimating packages.
Potential applications of these technologies include scanning historic and other buildings to ensure their preservation as well as planning future renovations; designing and 3D printing of architectural building models; surveying and layout; and improving construction estimating and scheduling to reduce costs.
“Working with Trimble represents the culmination of a fruitful, multi-year collaboration between CSU’s Department of Construction Management and Trimble,” said Jon Elliott, assistant department head and undergraduate program coordinator in the Department of Construction Management.
“Through numerous pieces of Trimble hardware and software applications, students gain important exposure to cutting edge technologies in surveying, virtual design and construction (VDC)-based estimating, site logistics, 3D modeling, building energy performance analysis, laser scanning, photogrammetry, and so on.
“Beyond the applications, Trimble’s dedicated employees provide outstanding educational opportunities through software demonstration and training. Through this exciting collaboration, Trimble is making significant contributions to our goal of preparing construction management students for a technologically advanced and dynamic construction industry.”
“Collaborating with CSU’s Department of Construction Management has been exciting. Trimble’s portfolio is highly relevant for students at the university,” said Roz Buick, Trimble vice president. “It will be rewarding to see the next generation of architecture, engineering, construction and building operations professionals experience the breadth and depth of our construction lifecycle solutions. We also look forward to supporting and learning from these new professionals as they experience and apply our solutions to real-world applications in their curricula.”
The gift was made to CSU’s Construction Management Program in the College of Health and Human Sciences.
Komatsu Australia and Skycatch Inc. are partnering to boost the efficiency of construction, mining and quarry sites across Oceana with the High Precision Package.
The High Precision Package is also known as Komatsu’s Everyday Drone Solution, a key component to the Smart Construction workflow.
The Everyday Drone contains the Explore1 high-precision UAV, the Edge1 integrated GNSS base station and edge compute module, and the Viewer, an online data visualization and analysis tool, packaged into a commercial-grade kit.
High-precision package. (Photo: Skycatch)
The Everyday Drone allows a user to experience time to data without needing ground control points (GCP), and the ability to seamlessly integrate precision aerial data into their Smart Construction Workflow.
In common construction workflows, the time to data using traditional surveying methods could take weeks until project stakeholders can view or analyze their job site data. With the Edge1, customers are able to leverage a seamless GCP free workflow that consistently delivers sub 50-mm accurate data, in arbitrary or local coordinate systems within 30 minutes, saving countless hours and labor costs.
“We are now using the Everyday Drone at the start of projects to collect whole site information for pre-tender and bidding capability, comparing against 3D design surface to provide fleet and project managers real, accurate information viewed in the Smart Construction Application,” said Aaron Marsh, national technology solution expert manager, Smart Centre, Komatsu Australia. “This allows them to work out their cut and fill volumes with accuracy from the beginning, and enables the project tender team to select the right machines for the project optimising fleet recommendation and empowering the team to make the right, data-based decisions from the start.”
“Skycatch is proud to offer a better way of accessing precision data on-site. With traditional methods, the solutions are piecemeal, cumbersome, and time-consuming,” said Christian Sanz, Skycatch founder and CEO. “Now, customers are able to make informed decisions about changes to what was planned and what is actually happening on site in near real-time, ultimately providing greater productivity, increased profit and reducing project risk from beginning to end,”
Customers tested the receptiveness of the Everyday Drone Solution, said James Mackenzie, national remote support manager at Komatsu Australia. They first tested in civil construction, and then quickly expanded into quarry sites. Mackenzie was able to survey six quarries in five days for different customers, post-processed in the cloud, receiving the data back the next day.
“Compared to a traditional survey, this is 100% more productive and efficient,” Mackenzie said. “By using the Everyday Drone, customers are no longer putting themselves in harm’s way, surveying around heavy machinery or climbing up unstable stockpiles at risk of twisting an ankle.”
He also noted that customers appreciated the fast turn-around time, the ease of use, and the ruggedness of the products.
“Skycatch’s ability to provide near real-time data throughout the entire project is vital, and being able to deliver that to the customer, supervisor and give project teams the ability to make decisions throughout the project easily with usable, accurate data is key to the success of the project as a whole, not just in siloed environments is priceless,” Marsh said.
A series of documentary videos on automation and technology in the construction and agriculture industries covers drone inspection of infrastructure among other new trends. Filmed in the U.S., the Netherlands, United Kingdom, and Germany, the series of brief films produced by Topcon Positioning Group emphasizes how technological advancements have changed infrastructure — how it is designed, built and maintained — and what to expect going forward.
“The infrastructure industry is changing quickly, and this video series highlights how this advancement is part of a larger story of technology changing the paradigm everywhere. To stay on top, businesses will need to adopt automation and new technology,” according to Topcon spokesperson Jackie Ferreira.
A spokesperson from Intel describes how drone inspection facilitated data gathering and project planning for a complex restoration project on the Great Wall of China, in an area with very difficult access.
Trimble has introduced its Groundworks Machine Control System, a solution for drilling and piling operations. The next generation system that enables contractors to perform drilling and piling operations quickly, safely and accurately: with centimeter-level accuracy.
Using the large touch-screen display, operators can personalize the interface to match their workflow. In addition, a variety of configurable views make it easier for users to achieve maximum productivity. The software aligns with other solutions in the Trimble Civil Engineering and Construction portfolio to make company-wide training faster and easier.
“Engineered for ease of use, Trimble Groundworks features an updated, intuitive user interface designed for construction environments,” said Scott Crozier, general manager for Trimble’s Civil Engineering and Construction Division. “Contractors can achieve centimeter-level accuracy with stakeless navigation, which reduces rework and decreases the need for personnel working near the machine during operation.”
Drilling. Trimble Groundworks Machine Control System for Drilling gives contractors the ability to drill to the specified location, depth, orientation and inclination angle. Better rock fragmentation and lower hauling costs can be achieved by optimizing drill hole spacing, angles, and the location of the machine for a more even blasting pattern, according to the company. The auto stop feature automatically stops drilling at target elevation to reduce overdrilling, leading to flatter benches and reduced wear and tear on machines, which can result in significant cost savings.
Minimizing the need for stakes and construction surveying, Trimble Groundworks can help promote jobsite safety by reducing the number of people working near the machine while drilling. Also, avoidance zones can be set to keep operators from entering hazardous areas. With Trimble Groundworks, machines can operate 24 hours a day, 7 days a week in almost any conditions, decreasing the chance of delays due to darkness or inclement weather.
Piling. The system enables contractors to increase operational efficiency and reduce surveying costs associated with staking and as-built checks. Navigation time between piles is reduced. Less time moving the machine and more time piling maximizes daily production, which can increase revenue.
Built-in, automated quality assurance and quality control reporting includes the capture of start and end positions, time and elevation as well as actual embedment depth, blow count reporting, and inclination and orientation control. In addition, unique system logins allow managers to filter reports by operator for better accountability, production optimization and forecasting.
Senators Joni Ernst (R-IA) and Tammy Duckworth (D-IL) joined Representatives Dave Loebsack (D-IA) and Don Bacon (R-NE) in launching the Congressional GPS Caucus in March. This bipartisan, bicameral caucus will elevate the ever-increasing importance of GPS technologies to the U.S. economy and infrastructure. As evidence of that, today more than 3.3 million jobs in the United States rely heavily on GPS.
Agriculture is front and center in the states and districts these policymakers represent, and the cost savings as well as jobs and family incomes are noteworthy. Nationwide, GPS has led to $8.2 billion in savings through precision agriculture, while yielding increases in grain production across the country. Further, GPS has become an indispensable and reliable part of the country’s national infrastructure. Public and private investment in GPS-based technologies and services have produced a steady stream of innovations, making the U.S. a global leader in the sector.
The GPS Caucus will prioritize ensuring GPS signals remain continuously available, accurate, reliable and resilient. To better support the long-term health and future of GPS, the caucus plans to host educational briefings and technology demonstrations, in addition to advocating for policies that keep GPS at the forefront. On April 2, these efforts will kickoff with a “GPS 101” educational briefing on the Hill featuring remarks from Senator Duckworth, Representative Loebsack, Colonel Curtis Hernandez, US Air Force Director National Security Space Policy, National Space Council and industry leaders from Deere & Company, Garmin and Trimble.
To further reaffirm the critical importance of GPS, the GPS Caucus introduced concurrent resolutions in both the Senate and House. The resolutions outline the economic benefits of GPS, totaling more than $68 billion to the U.S. economy each year, and the sectors GPS technology supports, none of which would be possible without the contributions made by the men and women of the Air Force who maintain the GPS constellation.
As efforts to advance 5G, precision agriculture and smart cities continue, GPS will only become more valuable to modern-day operations and it remains critical that policymakers, companies and industry leaders alike, foster policy that keeps GPS at the forefront.
Topcon releases upgrade of MAGNET software suite with new features and organization.
Topcon Positioning Group released the newest edition of its suite of software solutions — MAGNET 5.1. The upgrade is packed with new features, modules and support, as well as a reconfiguration of the Office portfolio designed for simplicity.
The HiPerVR GNSS receiver. (Photo: Topcon)
New updates to MAGNET Field include support for the new HiPer VR GNSS receiver, a piping and trenching module with new capabilities specifically for the oil and gas segment, as well as the ability to orient and scale a PDF directly on a field controller and set it as a background image.
“The new piping and trenching module greatly improves the COGO, mapping, and exchange functions for in-field oil and gas pipeline design and construction,” said Jason Hallett, vice president of global software business development at Topcon. “Simplified workflows deliver an alignment, profile, and cross-section set for loading into 3DMC for pipe trench excavation. Additionally, customers can now import a PDF drawing as a background image in MAGNET Field. Simply set the insertion point and then rotate and scale by selecting points or lines,” said Hallett.
New additions to MAGNET Office include a reconfiguration of the portfolio, designed for simplicity, integrated workflows and better service plans. The service plans and subscriptions for MAGNET Office now include MAGNET Enterprise, license check-in and check-out, direct email support and an eLearning fundamentals course.
Additionally, the E-commerce user-experience has been greatly improved with a new webstore. Direct email user support is currently offered at this web address.
“The newly optimized product portfolio allows customers to easily select the appropriate Office software product best for their common project demands. The new office structure includes five main products named: project, construction, site, survey and layout, which are consolidated packages of the various MAGNET software services for ease of use and bundling.
“MAGNET Site, MAGNET Construction, and MAGNET Project now include all of the Viasys VDC Modeler and Explorer functionality for infrastructure BIM modeling and visualization, and MAGNET Project adds even more power by including the DynaRoad mass-haul modules Plan, Schedule and Control,” said Hallett.
Additionally, MAGNET Enterprise now offers concurrent login to MAGNET Field, Enterprise and Office with a single set of login credentials.
DIRT, the AMW Machine Blade Control Solution. (Photo: AMW)
AMW Machine Control Solutions, a subsidiary of CHC Navigation, has introduced four new solutions for the survey, construction and agriculture markets, all of which run on Android and CHC Navigation GNSS tablet hardware.
GRADE I and II Products. GRADE I runs on a CHC Navigation industrial tablet and utilizes an internal meter-accurate GNSS receiver for field workers and supervisors to view layered maps including design files, topo or Google Maps for locating elevations and topographical features.
GRADE II adds centimeter elevation and positioning accuracy with an external CHC Navigation RTK-capable GNSS receiver that wirelessly communicates with the tablet.
GRADE II collects topographic data on the jobsite by walking or driving the area, eliminating surveyor stakes and providing accurate data for earth-moving operations. The density of elevation points can be adjusted. The GRADE II “Smart Base” allows a user to establish RTK control points.
DIRT I and II Products.
DIRT combines GRADE II mapping functionality with automatic blade control for skid steer, scraper, grader or dozer applications for rough and fine land-shaping activities on large or compact equipment. DIRT is available as DIRT I or DIRT II versions depending on the type of blade control needed. Utilizing additional sensors, DIRT II adds the ability to manage cross slopes.
DIRT includes an RTK GNSS, inclinometers, tablet computer, CANBUS controller and DIRT software running on a CHC Navigation tablet. The tablet wirelessly connects to the RTK receiver and other sensors, making the system easily portable so it can be reinstalled on other equipment.
For agriculture applications, AMW Solutions’ proprietary algorithm within the DIRT solution results in accurately graded surfaces within the limits of the equipment.
Topcon Positioning Group released a new workflow bundle designed to modernize concrete FFL (floor flatness and levelness) applications.
A new ClearEdge3D development and sales partnership with a leader and pioneer in 3D laser scanning software for construction QA/QC, Rithm, is prominently advancing the Topcon concrete application offering with a new hardware and software bundle option.
It is part of the Topcon comprehensive approach to modernize core concrete applications such as layout, quality control and concrete screed with the latest capabilities in precise positioning technology.
Implementing Rithm on projects for wet, or dry concrete scanning is designed to allow the opportunity to perform FFL analysis directly from scan data loaded into the Autodesk Navisworks software. Operators can find floor flatness and levelness mistakes in near real time from scan-to-finish. The data Rithm provides allows project teams to easily visualize high and low areas with elevation and deviation heat-maps and contour maps.
“By bundling this software with Topcon’s GLS-2000 scanner, contractors can improve their QA workflows to reduce floor profiling costs by performing FFL analysis in-house in near real time,” said Alok Srivastava, Topcon director of product management. “Through the integration with Navisworks, Rithm provides contractors fast, and detailed ASTM E1155 compliant FFL reports with streamlined floor flatness and levelness analysis, thereby cutting down time on waiting for scanning analysis, increasing productivity.
“The integrated workflow including the GLS-2000, post-processing with MAGNET Collage and QA analysis with Rithm software achieves an optimized end-to-end workflow — from the hardware to software end deliverables,” said Srivastava.
The new real-time FFL application is part of an overarching Topcon approach to modernize concrete applications with precise positioning technology.
Topcon GT series robotic total stations combined with integrated MAGNET software incorporate a BIM-integrated workflow to layout and verify construction quality in the field.
Additionally, Topcon offers machine control systems for robotic concrete screed applications. After importing an easily created 3D model, concrete can be poured and placed more efficiently with advanced screed technology designed to dramatically speed up the screed process and increase quality with precision-guided machine control.
“With our real-time position information constantly updating, you efficiently manage material as it’s placed — delivering the highest quality in a fraction of the time,” Srivastava said.
Mountainous areas present special problems for surveyors, overcome by the expanded availability of multi-GNSS. (Photo: Trimble)
Today’s GNSS satellites transmit on three or more carrier frequencies. The quality of the data in these signals from GPS, BeiDou, Galileo, GLONASS and QZSS reveals the expected measurement precisions. This article explores the noise of the range residual and ionospheric residual to indicate the oncoming capabilities.
Today, four GNSSs transmit various codes on various carrier frequencies: the USA’s GPS, Russia’s GLONASS, Europe’s Galileo and China’s BeiDou. Most of the carrier phase and pseudorange data are available using civilian GNSS receivers. Improvements in signal quality as well as reliability of the satellites are foreseen through the generations, as well as the introduction of new signals, such as L1C, L2C, L5 carrier and codes, and M-codes, on top of the existing L1-C/A code and the P(Y) code on both L1 and L2. Improvements are also seen in boosting the transmitting power.
This article investigates the use of two approaches to analyze the relative noise in the various carrier phase and pseudorange observable for GPS, BeiDou, Galileo, GLONASS and Japan’s Quasi-Zenith Satellite System (QZSS) augmentation. Two approaches analyze the relative noise in the observables: the range residual and the ionospheric residual. Both techniques can also be used to detect cycle slips.
Range Residual
UAV survey operations benefit from multi-GNSS receivers. (Photo: Septentrio)
The range residual is simply the change from one epoch to the next in the difference in the range calculated using the pseudorange and the range calculated by the carrier phase on a specific frequency. The pseudorange values are scaled using the wavelength to an equivalent range in units of the carrier’s cycles rather than meters. Equation 1 illustrates the range residual between the pseudorange ρ on a specific carrier frequency and the carrier phase observable φ, using the wavelength λ of the carrier to scale the pseudorange. The values of these observables are compared between adjacent epochs.
RR = (p/λ) – φ (1)
Two adjacent epochs are used, as then the integer ambiguity value, as well as the ionospheric and tropospheric errors, and satellite and receiver clock errors are the same, or negligibly different at such small (<1 s) epoch intervals. Therefore, these are all canceled out, and the resulting value is the measurement receiver and observable noise. The pseudorange observable will be significantly noisier than the carrier phase observable, therefore this method is a good way to calculate the measurement noise for the pseudoranges.
Ionospheric Residual
Surveyors work the Berezitovy mine in the North Amur region of Russia. (Photo: Javad GNSS)
If the carrier waves traveled only through a vacuum, then a phase observation from a specific satellite to a specific GNSS receiver could be scaled and converted to an equivalent phase measurement on another frequency using the frequencies of the carrier waves. However, as the signal passes through the ionosphere, systematic errors that are frequency dependent are introduced, so it is not possible to directly convert from one carrier phase value to another for a specific range measurement. The error is known as the ionospheric residual, and this will change slowly over time as the satellite passes overhead and the ionosphere being passed through changes, and also as the ionosphere slowly changes its characteristics over time, mainly due to the sun’s activities.
Equation 2 shows the calculation, using L1 and L2 carrier phase readings and corresponding frequencies, used to calculate the ionospheric residual. Again, the difference in the ionospheric residual values between adjacent epochs is used, as in the same way as the range residual values, external noise sources are eliminated.
(2)
Results
The results presented here are a subset of a much larger set. Figure 1 illustrates the range residuals for L1 and L2 as well as the L1L2 ionospheric residual for PRN32 (Block IIA satellite).
Figure 1. L1 range residual (left) L2 range residual (center) and L1L2 ionospheric residual (right) for GPS PRN32 (Block IIA) satellite. (Charts: Authors)
Figure 2 illustrates the L1 and L5 range residuals and the L2 (C-code) L5 ionospheric residual for PRN01 (Block IIF satellite).Both figures’ data are for the complete passing of the satellites from horizon over and back down again.The data for PRN32 is all that exists in the datafile, as this satellite only transmits L1 CA code and P(Y) code, as well as L2 P(Y) code, and corresponding carrier values.
Figure 2. L1 range residual (left) L5 range residual (center) and L2 (C code) L5 ionospheric residual (right) for GPS PRN01 (Block IIF) satellite. (Charts: Authors)
PRN01 is a block IIF satellite, and data for L1 CA code, L2 P(Y) code as well as L2 C-code, L5 code, and corresponding carrier phase values are recorded in the datafile.The block IIF satellites can result in four range residual values and five ionospheric residual combinations.Figure 2 only illustrates three of these combinations.The data were obtained from the Curtin University GNSS repository on Sept. 1, 2015, gathered at a 1-Hz epoch interval; 29,908 epoch of data were gathered for PRN32, and 26,073 epochs for PRN01.
It can be seen from these figures that the L1 range residuals are similar in characteristics for both PRN01 and PRN32.The values are noisy at the start and the end of the time series, indicating that the CA code is more prone to noise at low elevations.Comparing these to the L2 (PRN32) and L5 (PRN01) range residuals, we can see that both the L2 and L5 range residuals are not as prone to low elevation noise. Also, the two L2 and L5 range residuals are visually similar in characteristcs.By comparing the L1L2 and L2L5 ionospheric residuals (Figure 1, right, and Figure 2, right), we can see that the L1L2 combination is slightly noisier than the L2L5, in particular at low elevation angles.
If we compare BeiDou ionospheric residual results, we can see the comparison of noise on the three ionospheric residual combinations, B1B2, B1B3 and B2B3, as well as the results from the three types of satellite orbits, ie MEO, IGSO and GEO. Figure 3 illustrates the ionospheric residual results for PRN07 (IGSO) for the three frequency combinations, from data gathered on a static pillar located on top of the University of Nottingham Ningbo China’s Science and Engineering Building.
Figure 3. Ionospheric residual results for BeiDou PRN07 (IGSO) for combinations B1B2 (left), B1B3 (center), B2B3 (right). (Chart: Authors)
Figure 4 illustrates the ionospheric residual results for PRN01 (GEO) for the three frequency combinations.
Figure 4. Ionospheric residual results for BeiDou PRN01 (GEO) for combinations B1B2 (left), B1B3 (center), B2B3 (right). (Chart: Authors)
Figure 5 illustrates the ionospheric residual results for PRN12 (MEO) for the three frequency combinations. Here it can be seen that the B2B3 combination is generally less noisy than the B1B2 and B1B3. In addition to this, it can be seen that when the MEO and IGSO satellites are at lower elevation angles, the observables also become noisier. The GEO satellites have a constant elevation angle, and do not experience this phenomenon.
Figure 5. Ionospheric residual results for BeiDou PRN12 (MEO) for combinations B1B2 (left), B1B3 (center), B2B3 (right). (Charts: Authors)
Detailed Results
The data, gathered on a single GNSS receiver located at the University of Curtin’s GNSS research center, was downloaded in BINEX format and converted into RINEX 3.02 format using RTKLIB software. Software was developed by the authors in Matlab in order to interrogate the data files and implement the range residual and ionospheric residual algorithms. RINEX 3.02 format was chosen due to its compatibility with multi-GNSS and multi-frequencies.
Industrial UAV applications such as construction draw benefits from multi-GNSS receivers’ capabilities. (Photo: Skycatch, Swift Navigation)
Results are presented for both ionospheric residual and range residual results for various GNSS. These results have been calculated with varying elevation mask angles, ranging from 0° to 55° at 5° intervals. The RMS values of the resulting ionospheric residuals and range residuals were calculated and plotted against the respective elevation mask angle for each satellite and frequency combinations. This illustrates the influence of the elevation mask angle used on the results.
Typically, tens of thousands of epochs of data were used for every plotted point in the following figures. Further to this, not only are the results for the various frequencies and frequency combinations for the various GNSS illustrated, but also the various satellite types, MEO, GEO and IGSO, and various satellite Blocks for GNSS. GPS Block IIA (PRN04 and PRN32), Block IIR (PRN14), Block IIR-M (PRN31) and Block IIF (PRN01, PRN26, PRN25) data were all analyzed. Thus, the comparison of the various frequencies within each satellite system are illustrated, as well as the variations by comparing the various satellite constellation types and the various generations of GPS satellites.
Surveying accuracy is critical to roadway construction. (Photo: Leica Geosystems)
The BeiDou data illustrated are MEO (C12, C14, C11), IGSO (C09, C10, C07) and GEO (C01, C02). The data used were gathered on Sept. 1, 2015, in order to include GPS Block IIA satellites (PRN04 and PRN32). PRN32 was retired in June 2016, and PRN04 was taken out of active service in November 2015, but the satellite was reactivated in March 2018, this time broadcasting PRN18.
Figure 6 illustrates RMS of the range residual results for GPS (a), BeiDou (b), Galileo (c), GLONASS (d) and QZSS (e) respectively. These figures have been drawn so that the y-axis ranges are the same for each, hence illustrating the relative values.
Figure 6A illustrates the range residual results for GPS. It can be seen that the L1 CA code results are the noisiest, with PRN14 being the noisiest, followed by PRN31, PRN26, PRN01, PRN04, PRN25 and PRN32. It can also be seen with these results that lower elevation angle mask increases the noise level. Both the L2 and L5 code results are less noisy.
Figure 6A. RMS range residual results for GPS. (Chart: Authors)
Looking at the detail, the L5 code results is less noisy than the L2 and affected less than the L1 results by the changes in elevation mask angles used. Interestingly enough, the data file includes both the L2 P(Y) code and L2C code results. L2C only exists on the Block IIR-M and Block IIF satellites. The L2C code results are generally noisier than the L2 P(Y) code.
Figure 6B illustrates the results for the range residuals for the BeiDou satellites. Here it can be seen that the B1 code is affected more by low elevation mask angles than B2 and B3. It can also be seen that both the geostationary satellites’ B1 results stand out, with satellite C02 being noisier than C01. The B2 and B3 values for both these GEO satellites are bunched up with the majority of the other results towards the middle of the figure. The pairs of B2 and B3 results for the GEO satellites are close to each other in values, and the pairs of B2 and B3 results for the other satellites are also close to each other.
Figure 6B. RMS range residual results for BeiDou. (Chart: Authors)
It can also be seen that the range residual results for BeiDou are generally less noisy than than GPS, in units of cycles.
Similarly, for Galileo, Figure 6C, the E1 results are worst, and affected more by low elevation masks. Again, generally the Galileo results are seen to be improved over GPS. The GLONASS results, Figure 6D, illustrate that the L1C results are generally noisier, and then the L1P, followed by L2C and L2P. PRN09 is also consistently generally noisier than PRN10. Finally, Figure 6E illustrates the results for QZSS. Again, L1C is the noisiest and affected most by low elevation mask angles.
Figure 6C. RMS range residual results for Galileo. (Chart: Authors)Figure 6D. RMS range residual results for GLONASS. (Chart: Authors)Figure 6E. RMS range residual results for QZSS. (Chart: Authors)
Figure 7 illustrates the ionspheric residual results for the same satellites as Figure 6. This time, however, the resulting ionospheric residual values are calculated using pairs of data from the same satellite on different carrier frequencies. The range residual results compare the code and carrier from specific satellites and frequencies.
Figure 7(a) shows that the ionospheric residual results are affected by low elevation masks, and that the L1L2CW (L1 CA code and L2 P(Y) code available on all the satellites) combinations are the noisiest, followed by L2L5WX (L2 P(Y) code and L5 code available on Block IIF satellites, PRN 26, PRN01, PRN25), followed by L1L2CX (L1 CA code and L2 C code available on Block IIF and Block IIR-M satellites, PRN31, PRN26, PRN01 and PRN25), followed by L1L5CX (L1 CA code and L5 code, Block IIF satellites, PRN01, PRN25, PRN26) and finally the least noisy were the L2L5XX results (L2 C code and L5 code available on Block IIF satellites, PRN26, PRN25 and PRN01).
Figure 7A. Ionospheric residual results for GPS. (Chart: Authors)
Figure 7(b) illustrates the BeiDou ionospheric residual plots, illustrating that satellite C14 is much noisier for all three combinations of B1B3, BB1B2 and B2B3 in that order. The B1B2 combinations for the satellites are generally the noisiest, and then the B1B3 and B2B3 combinations are intertwined. The Galileo results again illustrate that the E1 combinations are generally noisier, and again we see the effect of low elevation angle masks, Figure 7(c). Generally, however, the Galileo results are less noisy than GPS, as are the BeiDou results.
Figure 7B. Ionospheric residual results for BeiDou. (Chart: Authors)Figure 7C. Ionospheric residual results for Galileo. (Chart: Authors)
The GLONASS results are again generally the noisiest, and again PRN09 is noisier than PRN10, with the L1P combinations being noisier, Figure 7(d). Figure 7(e) for QZSS shows that there are generally two groups of results. The upper set consists of L1L2ZX, L1L5ZX, L1L2XX, L1L5XX, L1L6ZX and L1L6XX from highest to lowest noise respectively. The lower, less noisy, group consists of L1L2CX, L1L5CX, L2L5XX, L2L6XX, L1L6CX and L5L6XX from highest to lowest noise respectively. Further details about the various codes and carrier values can be found in the RINEX 3.02 manual produced by the IGS.
Figure 7D. Ionospheric residual results for GLONASS. (Chart: Authors)Figure 7E. Ionospheric residual results for QZSS.(Chart: Authors)
Conclusions
A surveyor checks an urban construction project. (Photo: Topcon)
These preliminary results illustrate that there are differences in the noise values for various GNSS, frequencies as well as satellite generations and orbit types. It can be seen that generally L1, B1 and E1 have noisier results, and are affected moreso by low elevation mask data, and hence multipath. It can also be seen that newer generations of satellites do indeed produce better quality data.
Some specific satellites produce lower quality data such as GLONASS PRN09 and BeiDou C14. This could be due to multipath produced at the satellite.
Today roughly 100 GNSS transmit data, and typically users can gather data from 30 to 50 at any time. Positioning requires nowhere near this number of satellites, therefore decisions are needed as to which satellites and which data to use in a positioning solution. Our findings imply that our approach could be used in such decision-making in GNSS processing software, helping the software to choose the optimum satellites to draw from in a positioning solution.
Acknowledgments
This work described in this article was first presented at the FIG 2018 conference held in Istanbul, Turkey. The authors acknowledge the use of data supplied from the Curtin University GNSS Centre.
Manufacturers
The GNSS receiver used is a Trimble NET R9, and the antenna is a Trimble TRM 59800.00 SCIS choke ring antenna. A ComNav K508 GNSS receiver supplied some of the BeiDou results.
GETHIN WYN ROBERTS is an associate professor at Fróðskaparsetur, the University of the Faroe Islands. He is past Chairman of the FIG’s Commission 6, Engineering Surveys, and previously held posts at the University of Nottingham both in the UK and in China. He holds a Ph.D. in engineering surveying and geodesy from the University of Nottingham.
CRAIG M. HANCOCK is an associate professor in Geodesy and Surveying Engineering and the head of the Department of Civil Engineering at the University of Nottingham, Ningbo, China as well as the head of the Geospatial and Geohazards Research Group. He holds a PhD from the University of Newcastle Upon Tyne.
XU TANG is a research fellow at the University of Nottingham, Ningbo, China. He holds a PhD from Nanjing University.
Uplift adds commercially trained pilots and expands PrecisionHawk’s industry expertise and relationships in drone-based services for construction and facility management nationwide.
Uplift specializes in the delivery of turnkey inspection services for construction, building information management and real estate, and has provided drone services for national and global brands.
Its nationwide network of commercially trained drone pilots will join PrecisionHawk’s Droners.io network of more than 15,000 drone pilots. Suzanne El-Moursi, CEO of Uplift, will join PrecisionHawk’s executive leadership team managing the company’s construction line of business.
This is the fifth acquisition for PrecisionHawk in 2018. Early acquisitions include Droners.io and Airvid. In September, it purchased both Hazon Solutions and InspecTools which specialize in the delivery of inspection services and technology for the energy industry. Their integration with PrecisionHawk has created dynamic synergy, providing solutions that elevate airborne intelligence and strengthen the data value chain for the enterprise.
Similar to the energy space, the construction industry has experienced a rapid uptake in the adoption of commercial drone technology. Drones are now one of the leading innovative technologies that are transforming the construction process since they decrease the need for lengthy visual inspections, reduce planning time, improve worker safety and identify problems.
Uplift Data Partners was formed in 2015 as a fully integrated subsidiary of Clayco, one of the nation’s largest architecture, engineering, design-build and construction firms, with more than $2 billion in annual revenue.
Through the acquisition, Clayco will exclusively source its construction projects to PrecisionHawk, and will serve on PrecisionHawk’s Board of Advisors to support the growth of the company’s services and software in the construction industry.
The PrecisionHawk UAV. (Photo: PrecisionHawk)
“PrecisionHawk is leading the commercial drone market by combining superior technology with deep expertise in the markets that they serve,” said Bob Clark, Clayco CEO. “Through this acquisition, Clayco customers gain access to a new level of technological sophistication for more scalable and robust operations, while continuing to benefit from Uplift’s deep understanding of the demanding nature of engineering and construction industry drone missions,.”
“This acquisition displays PrecisionHawk’s commitment to strengthening our technology and expertise in high-growth markets,” said Michael Chasen, PrecisionHawk CEO. “By combining PrecisionHawk’s leading-edge products and services with Uplift’s industry experience and training standards, our customers will receive best-in-class aerial data and analytics for complex construction and facility inspection projects through a simple and easy to procure process.”
“Our mission at Uplift is to support the modernization of the architecture, engineering and construction (AEC) industry by creating tools and training that improve the accessibility of drone services, thereby delivering true value to construction projects,” said Uplift CEO Suzanne El-Moursi. “The construction industry is uniquely rugged, yet defined by innovation and intelligence, and we are thrilled to join PrecisionHawk, a company that is both aligned to this mission and committed to the growth and expansion of the industry.”
Propeller Aero, a cloud-based drone analytics company, is partnering with DJI to create the Propeller PPK Solution leveraging the DJI Phantom 4 RTK drone.
The solution provides customers in the civil, mining, aggregates and waste management industries with a reliable and fully integrated drone mapping system, helping them collect highly accurate data from any worksite without the challenges of traditional workflows, the companies said.
The DJI Phantom 4 gathers data at a construction site. (Photo: DJI)
According to Propeller Aero, Propeller PPK Solution is a fully integrated software and hardware system that reliably provides photogrammetric model outputs in geodetic, projected or local coordinate systems.
The solution provides accuracy of 1/10 feet (3 cm) from independent checkpoints across small and large survey areas (checkpoints up to 1 km from GCPs). To capture surveys of this accuracy, all that is needed is one AeroPoint on the ground (over a known point if working in local coordinates).
The Propeller PPK Solution has been shown to reduce the time required to complete a drone survey by 70 percent as compared to a traditional workflow using multiple GCPs across a worksite, Propeller Aero said.
“DJI has led the drone market with their reliable and innovative products, and quickly demonstrated the ability for these machines to become useful tools in the heavy civil and natural resource industries,” said Rory San Miguel, CEO of Propeller Aero. “Globally, these industries are seeing real cost savings and efficiencies through cloud-based analytics and using innovative new technologies like PPK drones combined with AeroPoints. Accurate data is paramount to worksite analytics and Propeller has always been obsessed with helping teams achieve this. We introduced the world’s first smart ground control point, AeroPoints, and now we’ve partnered up with DJI to build an end-to-end PPK solution.”
On today’s construction sites, lack of project data costs businesses more than $177 billion annually. To help solve this problem, Propeller developed a tightly integrated PPK workflow across the DJI Phantom 4 RTK drone, an AeroPoint, and Propeller’s cloud processing platform that visualizes real-time site data. Surveyors and contractors can Propeller PPK solution to gather verifiable, trustworthy data to help make data-driven decisions and prevent costly mistakes, the companies added.
“Propeller’s deep expertise in aerial mapping and analytics coupled with DJI’s industry-leading open-platform drone hardware creates a highly accurate turnkey solution,” said Jan Gasparic, director of strategic partnerships at DJI. “We are excited about this partnership because it broadens the use of DJI drones to deliver accurate data at a cost-efficient price point, helping teams better answer questions about site progress and productivity.”
The complete PPK solution will be distributed through channel partners, including Trimble’s SITECH distribution network. Trimble Stratus, a 3D cloud-based visualization platform developed by Propeller, along with AeroPoints, is already integrated with Trimble Connected Site solutions.
“The advent of drones in the construction industry has improved efficiencies, and Trimble Stratus users are already benefiting from the ease-of-use and scalability of drone-based surveys,” said Scott Crozier, general manager, Trimble Civil Engineering and Construction. “With the new Propeller PPK Solution and Trimble Stratus software, we’ve seen first-hand how surveyors and contractors can collect aerial survey data in a fraction of the time it used to take, and get repeatable and reliable results.”
Nearmap high-resolution aerial image showcasing new toolset in MapBrowser, captured Sept. 15, 2018. (Image: Nearmap)
Nearmap has introduced a complete measurement toolset in MapBrowser for the solar, roofing and other rooftop industries.
The new tools allow users to measure roof-pitch, height, width and area, enabling roofers and solar installers to confidently measure rooftops and structures from high-resolution oblique aerial images, the company said.
The new MapBrowser helps customers significantly reduce onsite visits during the quoting and planning stages of projects and complements their remote roof/site inspection workflows, giving many small businesses the power of expensive systems that only large companies use.
“Gone are the days of climbing on roofs to take measurements,” said Tony Agresta, executive vice president of product at Nearmap. “Delivered to the cloud within days of capture, our aerial imagery allows roofers, solar companies and other small businesses to carry out assessments from the comfort of their office. Once the domain of large companies, the new features provide businesses of all shapes and sizes with the tools they need to save time, plan and estimate more accurately at a fraction of the price.”
Using Nearmap’s new tools, roofers and solar companies will be able to:
Prospect more efficiently by viewing and expanding opportunities through aerial maps instead of other, more traditional ways.
Process leads more quickly by qualifying prospects prior to visiting a potential job.
Reduce costs associated with the qualification and proposal stages.
Create better proposals using up-to-date, high-resolution photos, giving companies a better chance at winning a client’s business.
Close more sales with the most accurate and competitive quotes.
Increase revenue without adding systems or headcount.
Businesses in construction, home building, painting, insurance and other industries can also benefit from these new tools to accurately measure areas on properties in three dimensions. Nearmap’s aerial imagery can help users to show context for work being done, and the imagery can be annotated with notes, drawings and measurements that provide details of the plan.
Nearmap Oblique imagery can be accessed through a standard web browser using Nearmap’s intuitive MapBrowser application. In addition, Nearmap Oblique photos are published at sub-7.5cm ground sampling distance (GSD) — better than satellite imagery — which allows users to see great detail, Nearmap said.
