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REFAG 2022 abstract submission and registration opens

REFAG 2022 logo

The IAG International Symposium on Reference Frames for Applications in Geosciences (REFAG 2022), which is organized by the Aristotle University of Thessaloniki under the scientific coordination of Commission 1 of the International Association of Geodesy, will be held in Thessaloniki, Greece on October 17-20.

REFAG 2022  aims to address today’s theoretical concepts of reference systems and their practical implementation by space geodetic techniques and their combinations, underlying limiting factors, systematic errors and novel approaches for future improvements. The symposium welcomes contributions in all aspects of geodetic reference frames and their applications in Earth science studies, satellite navigation, and also other key areas of geomatics and geospatial information systems.

The scientific program of the symposium covers all topics related to the activities of IAG Commission 1 and its subgroups, including also other initiatives and projects which endorse the role of geodetic reference frames towards scientific exploration, sustainable development, land administration, disaster risk reduction and climate monitoring.

The deadline for abstract submissions for the symposium will be until July 20. Accepted abstracts will be notified by e-mail to the corresponding author by July 30. The submission form and submission information can be found at https://www.refag2022.org/abstract-submission/abstract-general-information/.

Early bird registration is available for REFAG 2022 until July 25. Registration information can be found here.

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OxTS Meeting accuracy demands

Mobile mapping using an OxTS xNAV650 INS and lidar sensor. Photo: OxTS

Mobile mapping using an OxTS xNAV650 INS and lidar sensor. Photo: OxTS

We discussed mobile mapping with Jacob Amacker, application engineer, OxTS.

How do you define “mobile mapping” as opposed to “surveying”?

We use the two terms interchangeably. Each one has a different connotation depending on where you are in the world and both can be useful. We use them to cover a broad range of use cases, but “mobile mapping” is used more specifically for land-based mapping of the environment. A typical application might be a van equipped with an INS [inertial navigation system] and lidar sensors.

“Surveying” can be used a bit more generally, applying to aerial or pedestrian-based mapping, but it does have the connotation of static mapping, which we do not typically handle.

What are your main markets for mobile mapping?

It is very hard to say. The world of mobile mapping is so diverse. However, lidar mapping could be seen as both the largest and the fastest-growing market in the surveying world as lidar has become widely affordable. Although our technology can be used with any surveying devices, at OxTS we particularly like to use lidar and are focusing on getting the best results from lidar data. This has included making our own point-cloud georeferencing software to maximize the potential of our navigation data in making point clouds.

What are the main differences between your devices for aerial mapping and for ground-based mapping?

We use the same INS device for both ground and aerial mapping. For use on manned aircraft, we would always recommend our highest accuracy system with the best IMU, the Survey+. The main source of inaccuracy in survey data will come from the IMU error over the range to the objects. Because most of this range is the aircraft’s altitude, this error is quite significant. For land-based mapping work, the measurements provided by the lighter and smaller xNAV650 are still suitable for many high-precision applications.

GNSS-INS integration has been done for decades. What is new and what are the remaining challenges?

It is now much more affordable to have very high-grade IMUs and GNSS receivers. Nevertheless, there will always be further improvements to be made to how the data streams are combined. On a similar note, other navigation aiding sources are increasingly being considered to supplement the IMU and the GNSS receiver — such as wheel speed sensors, lidar, camera odometry and others that can also be integrated to stabilize and improve the navigation data. Overall, it is very exciting what is yet to come out of INS technology. In recent years, it has become so good that people expect more and more from it, and this demand must be met. What happens when GNSS drops out? We are seeing increasing development to make the navigation data robust against challenges of any environment.

Given the IMU’s drift, for how long can your system function at an acceptable level in case of a GNSS outage?

It is difficult to put a number on what kind of drift is acceptable, as it depends on the application and the end-user requirements. Typically, half a meter of drift in one minute of GNSS-outage might be the goal for some of the higher-grade surveyors. Still others might only be satisfied with negligible drift.

What keeps the INS and the lidar unit synchronized during a GNSS outage?

The INS has an internal clock to keep the timing during a GNSS outage. Of course, this will not be as accurate as the atomic clocks on the satellites, but it is quite adequate to maintain survey-grade accuracy during GNSS outages. GNSS is still necessary to get the timing information in the first place, and this is a reliance that INS devices will want to remove in the future.

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AEVEX Aerospace: Taming the Wild West

Lidar point clouds can reveal very fine features, such as electric power lines. Photo: AEVEX Aerospace

Lidar point clouds can reveal very fine features, such as electric power lines. Photo: AEVEX Aerospace

We discussed UAV lidar mapping with Bob Stadel, vice president of Geodetics, AEVEX Aerospace.

What are the key remaining technical challenges in UAV lidar mapping?

With continuing improvements in UAVs, lidars, GNSS receivers and other sensors, the key to unlocking more efficiency and profitability in this market will be improving and simplifying workflows and processing. The next frontier is integrating AI and machine learning with digital twin models to create forecasting tools.

UAVs are much cheaper to operate than manned aircraft per hour, but not necessarily per square mile. UAVs can cover ground that cannot be mapped from a land vehicle; however, the latter have a much greater range.

You are correct. Each type of vehicle has its area of best utilization. Once we know what the customer wants from the data being collected, we can determine the size, weight and power (SWAP) of the payload needed, and then it’s a matter of analyzing cost versus capability and working with the customer to pick the right payload for the right vehicle at the right price.

What positional accuracy do you achieve for your point clouds?

With our GNSS-receiver-based navigation unit, which also includes an IMU and key IP [intellectual property] from our company, and the right combination of tools, we achieve an accuracy of 2 cm to 3 cm.

What are your key markets for UAV lidar mapping?

I believe it is still the Wild West in this market space. Really smart people are figuring out new ways to use these systems every day. We sell systems to teams doing high-end inspections of infrastructure, such as roads, bridges, corridors and power lines, as well as for land surveying and mining.

What was a recent application of one of your mapping systems?

One of our most recent success stories has been the launch of our Geo-ECTO-1 system. It features dual lidar sensors combined with a 360-degree FOV [field of view] camera and high-end GNSS receiver. It is ruggedized from the ground up and is meant for high-end survey and infrastructure inspection work. The payload is designed to quickly transition to a UAV-based system. Our two launch customers/partners are California-based survey companies Guida Survey and LACO Survey. It has been a great experience getting these systems up and running with our partners.

Our next adventure will be to work with UC San Diego’s Scripps Oceanographic Institute. We are proposing and demonstrating one of these systems to be used for analyzing cliff erosion on the beaches here in California, where several collapses have led to the loss of life. We want to support figuring out how to use the analyses to create a system that would give early warning of trouble spots. With these tools we can make our beaches much safer.

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Protempis launches GNSS timing receiver for OCP-TAP

OPC-TAP logoUltra-precise dual-band Protempis Res720 GNSS timing module provides nanosecond-level accuracy

Protempisformerly Trimble’s Time and Frequency Division — is providing its dual-band timing receiver Res720 embedded module to the Open Compute Project Time Appliance Project (OCP-TAP) for its open-sourced time card reference design.

In 2020, OCP-TAP started working on highly precise and hyper-scalable time synchronization services in its data center market, using a GNSS clock source and precision time protocol (PTP) technologies. OCP-TAP technology adds scalability and improves the accuracy of timekeeping within the infrastructure industry.

In 2021, OCP-TAP integrated its technology into the time card and introduced it as an open-source solution to build time servers.

The Protempis Res720 embedded module provides a highly accurate GNSS clock source to further increase the accuracy, resiliency and adoption of the OCP-TAP’s new time card duo, which was announced in an OCP Tech Talk on June 2.

OCP-TAP provides a new collaborative community focused on designing hardware and software to efficiently support critical timing accuracy and resiliency demands on computer network infrastructure.

Protempis Res720

Protempis’s Res720 embedded module adds a dual-band GNSS time reference to the time card to improve resilience, noise rejection and anti-spoofing and anti-jamming capabilities.

The Res720 GNSS embedded timing module is suitable for data centers, 5G Open RAN and XHaul, smart grids, industrial automation and SATCOM networks. It provides 5 ns timing accuracy, dual-band GNSS support and anti-jamming/anti-spoofing capabilities.

The Res720 embedded module provides unparalleled performance as a timing source in embedded systems, including to time servers, network interface cards, radio units and routing/switching devices for 5G, private wireless, Open RAN and data networks.

“Protempis brings its expertise in GNSS and network synchronization to Meta, the OCP-TAP, and the open-sourced time card. Their highly accurate dual-band GNSS product has shown how it can improve operations,” said Ahmad Byagowi. Byagowi is inventor of the Time Card, founder and project lead for OCP-TAP, and a research scientist at Meta.

“We are honored that our Res720 dual-band technology will be used for enabling time-sensitive applications over OCP-compliant and PTP-aware networks,” said Karen Guldan, Protempis president. “We look forward to a continuing partnership with OCP-TAP and global network leaders working to advance solutions to provide ongoing timing accuracy and resilience.”

Precisional, an affiliate of The Jordan Company (“TJC”), announced May 9 that it completed the previously announced transaction to acquire four industrial technology businesses from Trimble, including Protempis (formerly Trimble Time and Frequency).

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Seen & Heard: Xona satellites, Russian bombs, better emergency response

“Seen & Heard” is a monthly feature of GPS World magazine, traveling the world to capture interesting and unusual news stories involving the GNSS/PNT industry.


Xona’s first demonstration mission successfully completed testing at Experior Laboratories and prepares for launch on a Falcon 9 in May. (Photo: Xona)

Xona’s first demonstration mission successfully completed testing at Experior Laboratories and prepares for launch on a Falcon 9 in May. (Photo: Xona)

TAKING GNSS PRIVATE

At press time, Xona Space Systems’ first in-space demonstrator satellite, named Huginn, was ready to launch on May 25 aboard Space X’s Transporter 5 mission. Xona said the launch is a significant step toward realizing its high-performance commercial navigation system, a constellation of small, powerful satellites in low Earth orbit that will meet the navigation and timing needs of intelligent systems.


Photo: gorodenkoff/ iStock/Getty Images Plus/Getty Images

Photo: gorodenkoff/ iStock/Getty Images Plus/Getty Images

GEOLOCATED EMERGENCY CALLS

U.S. cellular carrier AT&T is rolling out location-based routing to automatically transmit wireless 9-1-1 calls to the appropriate call centers, rather than relying on which cell tower handles the call. Cell towers can cover a 10-mile radius, and overlap with more than one call-center boundary. With location-based routing, a device can be located and routed within 50 meters of the device location. The “Locate Before Route” feature from Intrado enables AT&T to use device GNSS and hybrid information to route the call to the right call center.


Russian fighter jets in better times. (Photo: Aterrassi/iStock/Getty Images Plus/Getty Images

Russian fighter jets in better times. (Photo: Aterrassi/iStock/Getty Images Plus/Getty Images

RUSSIAN NAVIGATION CHALLENGES

Russian jets have been found using GPS receivers, while ground vehicles use paper maps, according to the UK Express. The GPS receivers were found taped to the dashboards of Russian SU-34s downed in Ukraine because of “the poor quality of their own systems,” UK Defense Secretary Ben Wallace said in a speech. With many reports of maintenance and aging issues for the Russian military, most likely the jets did not have quality GNSS receivers rather than the fault lying with GLONASS.


A Russian short-range ballistic missile, believed to be an unexploded Iskander missile, was found near Kramatorsk, Ukraine, in this photo released March 9 by Ukrainian authorities. (Photo: National Guard of Ukraine handout via Reuters)

A Russian short-range ballistic missile, believed to be an unexploded Iskander missile, was found near Kramatorsk, Ukraine, in this photo released March 9 by Ukrainian authorities. (Photo: National Guard of Ukraine handout via Reuters)

UNEXPLODED BOMBS MAPPED

The HALO Trust is partnering with Esri to map unexploded ordnance in an immediate humanitarian response to the war in Ukraine. More than 10 million Ukrainians have been displaced by the war and many are forced to move across a landscape littered with unexploded rockets, bombs and landmines. In response, Esri has committed its cutting-edge geographic information system (GIS) software resources, expertise and staffing in support of HALO’s mission in Ukraine. HALO already is using GIS to map the heaviest conflict zones, and the partnership with HALO will support planning for future clearance operations.

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Orolia releases Skydel GNSS simulation software upgrade

Skydel 22.5 features advanced hardware-in-the-loop testing

Orolia has released Skydel 22.5, a significant software upgrade to its Skydel simulation product line that features advanced hardware-in-the-loop (HIL) testing solutions providing very low to zero effective latency.

The enhanced visualization tools can monitor internal latency through real-time curves showing when the data is generated and sent to the RF signal. Users can also review the transmission of HIL packets for optimizing the entire network’s latency, checking its stability (jitter), and that data is available and used at the right time in Skydel.

HIL testing is an essential step in the verification process of the model-based design (MBD) approach because it involves all the hardware and software that will be used operationally. HIL verification can test a standalone device-under-test (DUT) or, more generally, an entire complex system consisting of multiple DUTs in both open- and closed-loop architectures.

“The vast majority of problems encountered by engineers on HIL systems are related to poor control of the latency of the entire simulation chain, as they are insufficiently accessible, transparent and controlled on the competing systems,” said Pierre-Marie Le Veel, principal system architect and product manager for GNSS simulation. “Thanks to these tools, our high-end performance and well-known intuitive automation, Skydel dramatically reduces the implementation time of a HIL system (which can be very significant) and, therefore, the project’s overall cost.”

Photo: Orolia

Photo: Orolia

In addition to these tools, Skydel implements modern extrapolation algorithms that achieve zero effective latency. These algorithms make it possible to keep position errors negligible, even for equipment with very high dynamics used in national defense applications such as missiles, rockets and guided shells.

“These advanced HIL algorithms and tools are available – and with the same performance – on our Wavefront simulation systems to test controlled reception pattern antenna (CRPA) systems,” Le Veel added.

Additional constellations, signal types and options such as real-time kinematic (RTK) and multi-instance are available along with dedicated bundled simulation starter packages for automotive.

The upgrade is available at no additional cost for existing users operating Skydel 22.5. Application notes, support documents and tutorials are available online.

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GeoSLAM partners with Flyability on Elios 3 indoor drone

Photo: Flyability

Photo: Flyability

Flyability has unveiled the Elios 3, a collision-tolerant drone equipped with a lidar sensor for indoor 3D mapping. The drone is powered by a new SLAM engine called FlyAware that lets it create 3D models as it flies.

It also is accompanied by a new version of Flyability’s software for inspectors, Inspector 4.0.

The launch of the Elios 3 marks a new partnership with GeoSLAM. The Elios 3 comes with an Ouster OS0-32 lidar sensor, allowing inspectors to collect data for the creation of survey-grade 3D models using software from GeoSLAM.

The drone gives users real-time digital replicas of previously inaccessible areas with the inclusion of the lidar sensor and GeoSLAM’s Connect software. The drone is protected by a cage and has advanced collision-tolerance features that allow inspectors to fly it inside dangerous confined spaces such as boilers, pressure vessels and mines.

With its integration with Connect, the Elios 3 creates survey-grade point clouds. Fitted to the back of the drone, the lidar sensor maps the environment in real time using Flyability’s FlyAware SLAM algorithm.

Survey package option

Those that need highly accurate data can upgrade to the survey package, provided by GeoSLAM, providing access to the Connect software, as well as specialist Volumes and Draw modules. Powered by GeoSLAM’s established SLAM algorithm, Connect offers a simple and automated way to process point cloud data.

Using the survey package, data is processed to an accuracy of 8 mm, suitable for mapping hazardous environments such as mines and industrial applications including chimneys, production plants, warehouses, silos and tanks. Processed data can then be viewed in the easy-to-use 3D viewer and exported to industry-standard file types including LAZ, LAS, PLY and TXT for use in third-party software.

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Velodyne Lidar signs agreement with robotics company Boston Dynamics

The Boston Dynamics Spot robot equipped with Velodyne lidar. (Photo: Velodyne)

The Boston Dynamics Spot robot equipped with Velodyne lidar. (Photo: Velodyne)

Velodyne Lidar Inc. has signed a multi-year agreement for its lidar sensors with Boston Dynamics, a mobile robotics company best known for its “Spot” dog-like robot.

Boston Dynamics selected Velodyne’s sensors to provide perception and navigation capabilities for its highly mobile robots. The sensors enable mobile robots to operate autonomously and safely, without human intervention. They provide real-time 3D perception data for localization, mapping, object classification and object tracking.

Velodyne’s power-efficient sensors support autonomous mobile robots in a wide range of challenging indoor and outdoor environmental conditions, including varying temperature, lighting and precipitation, the company said.

Velodyne’s lidar sensors will enable the robots to autonomously navigate complex environments, safely avoiding obstacles and finding the fastest route to perform tasks in environments from manufacturing plants and construction sites to distribution centers and warehouses.

The Alpha Puck, Alpha Prime and Velarray M1600 lidar sensors. (Photo: Velodyne)

The Alpha Puck, Alpha Prime and Velarray M1600 lidar sensors. (Photo: Velodyne)

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Applied Sciences seeks submissions for GNSS issue

Applied Sciences logoManuscripts submissions are being sought for a special issue of Applied Sciences, which will be dedicated to “Recent Advances in GNSS High-Precision Positioning and Applications.”

Deadline for manuscript submissions is Dec. 30. Full instructions are available on the special issue website.

The goal of the special issue is to highlight recent developments in high-precision GNSS positioning models, algorithms and applications. The topics of interest include, but are not limited to, the following:

  • multi-GNSS multi-frequency PPP, RTK, PPP-RTK models and algorithms, making use of high-grade and low-cost equipment
  • quality characterization of smartphone GNSS observations
  • functional and stochastic models for multi-GNSS precise positioning with smartphones
  • characterization and handling of multi-GNSS inter-system and inter-/intra-frequency code and phase biases
  • ionospheric and tropospheric modeling
  • carrier-phase ambiguity resolution
  • GNSS-LEO observation modeling and integration
  • integrity monitoring
  • GNSS-based lunar navigation
  • satellite orbit dynamics.

Special-issue editors are Safoora Zaminpardaz and Dimitrios Psychas.

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Tallysman adds housed TW3885T dual-band timing antenna

Photo: Tallysman

Photo: Tallysman

Tallysman Wireless has added the housed TW3885T dual-band (L1/L5) Accutenna technology timing antenna to its line of GNSS products.

The dual-band TW3885T antenna supports

  • GPS/QZSS L1/L5
  • Galileo E1/ E5a/b
  • BeiDou B1/B2/B2a
  • GLONASS G1/G3
  • Satellite-based augmentation systems (SBAS) in the region of operation: WAAS (North America), EGNOS (Europe), MSAS (Japan) or GAGAN (India).

Historically, dual-band antennas and receivers commonly supported GPS L1 and L2 and GLONASS G1 and G2. In recent years, GPS, GLONASS, Galileo, BeiDou and NavIC have added GNSS signals in the L5 frequency band (1164-1217 MHz). As a result, the new dual-band GNSS standard has become L1 and L5. Tallysman’s new TW3885T antenna has been tuned to provide optimal support for both the upper (L1/ G1/E1/B1/) and lower (L5/G3/E5/B2) GNSS bands.

The TW3885T is housed in a through-hole mount, weatherproof (IP69K) enclosure. For permanent installations, L-bracket (PN 23-0040-0) or pipe (23-0065-0) mounts are available. Tallysman provides an antenna installation guide that recommends a 100-125 mm ground plane and provides antenna installation and cable connector waterproofing best practices.

The radio frequency spectrum has become congested worldwide as many new LTE bands have been activated, and their signals or harmonic frequencies can affect GNSS antennas and receivers. In North America, the planned Ligado service, which will broadcast in the frequency range of 1526 to 1536 MHz, can affect GNSS signals. New LTE signals in Europe (band 32, 1452–1496 MHz) and Japan (bands 11 and 21, 1476–1511 MHz) have also affected GNSS signals. Tallyman’s new TW3885T mitigates the effects of these new signals.