GPS World

Tag: IMU

  • Allystar offers dual-antenna GNSS-aided INS platform

    Allystar offers dual-antenna GNSS-aided INS platform

    The Allystar INS Platform — the company’s latest technology — is a dual-antenna, multi-frequency, multi-GNSS inertial navigation system (INS) that delivers accurate and reliable position, velocity and orientation, the company said.

    It is designed for a wide range of autonomous vehicle applications under the most demanding conditions.

    Allystar RTK/INS Evaluation Board V1.0. (Photo: Allystar)
    Allystar RTK/INS Evaluation Board V1.0. (Photo: Allystar)

    The Allystar INS Platform combines high-grade, six-axis, temperature-calibrated accelerometers and gyroscopes with a multi-frequency, multi-GNSS engine, the HD9300 series. HD9300 is a dual-antenna chip-grade real-time kinematic (RTK) GNSS receiver for accurate positioning and heading.

    GNSS-aided inertial navigation systems are widely used in autonomous vehicles. However, high-accuracy multi-frequency multi-GNSS receivers are usually too expensive for mass-market applications. The Allystar HD9300 series is a mass-market multi-band chip-grade receiver that concurrently support all civil bands in all GNSS constellations (GPS/QZS L1&L2&L5&L6, BDS B1&B2&B3, GAL E1&E5, GLO L1OF/L2OF) with an integrated RTK engine to achieve centimeter-level accuracy.

    The Allystar INS platform contains an on-board sensor-fusion filter, navigation and calibration algorithms for different dynamic motions of land vehicles. Key features include:

    • multi-band multi-GNSS chip-grade receiver
    • dual antennas
    • integrated RTK engine (up to 2 centimeters)
    • 100-hz update rate
    • OBD data adapter.
    Allystar OBD Data Adaptor V1.(Photo: Allystar)
    Allystar OBD Data Adaptor V1. (Photo: Allystar)

    The Allystar OBD Data Adapter (v1.0) enables users to read and monitor various sensors built into cars, obtaining the real-time vehicle speed and gear signals from the OBD interface, and then output AT commands by serial port or SPI. When connected to the Allystar RTK INS platform, the adapter allows for outstanding navigation accuracy, especially in urban areas, helping to increase accuracy and reduce position drift.

    An evaluation kit — including platform board, antenna and OBD adaptor — will be available in August.

  • Two little eyes that can see and navigate

    Two little eyes that can see and navigate

    The RealSense camera uses two fisheye lenses and an IMU to construct location awareness. (Photo: Intel)
    The RealSense camera uses two fisheye lenses and an IMU to construct location awareness. (Photo: Intel)

    The Intel RealSense Tracking Camera T265, designed for positioning and maneuvering mobile robots and other portable systems, includes an inertial measurement unit (IMU) that enables developers to create solutions with advanced depth-sensing and tracking capabilities. Intel introduced the camera in Q1 of 2019. An earlier model, the D435i, also includes an IMU but is a depth camera, not a tracking camera.

    As robots, drones and other autonomous mobile devices must — eventually — interact independently and intelligently with their environments, they must track their locations as they move, navigating unfamiliar spaces while discovering, monitoring and avoiding still and moving obstacles in real time.

    Block diagram of camera components. (Image: Intel)
    Block diagram of camera components. (Image: Intel)

    Moving toward that goal, the T265 includes two fisheye lens sensors, an IMU and an Intel Movidius Myriad 2 video processing unit (VPU), a system-on-chip component for image processing and computer vision at very high performance per watt.

    Vision-based simultaneous localization and mapping (V‑SLAM) algorithms run directly on the VPU with very low latency. The T265 has demonstrated less than 1% closed-loop drift under intended use conditions. It also offers sub 6 ms latency between movement and reflection of movement in the pose.

    The RealSense device measures 1 x 0.5 x 4 inches (108 mm x 24.5 mm x 12.5 mm), weighs around two ounces (55 g), and draws 1.5 watts to operate the entire system, including the cameras, IMU and VPU. Its spatial sensing and tracking capabilities are based on technology developed by RealityCap, acquired by Intel in 2015.

    The camera performs inside-out tracking: it does not depend on external sensors to understand its environment. Tracking is based on information gathered from the two fisheye cameras, each with a 163-degree range of view (±5 degrees) and capturing images at 30 frames per second. The wide field of view from each sensor keeps points of reference visible to the system for a relatively long time, even if moving quickly.

    Visual-Inertial Odometry. A key strength of visual-inertial odometry is that the sensors complement each other. The images from the camera are supplemented by data from the onboard IMU, which includes a gyroscope and accelerometer. The aggregated data from these sensors is fed into the SLAM algorithms.

    The algorithm identifies sets of salient features in the environment, such as a corner of a room or object that can be recognized over time to infer the device’s changing position relative to those points.

    The visual information prevents long-term drift from the inertial that degrades position accuracy. The IMU operates at a higher frequency than the cameras, allowing for quicker response and recognition by the algorithm to changes in the device’s position. A map of visual features and their positions is built up over time. In re-localization, the camera uses the features it has seen before to recognize when it has returned to a familiar place. The camera can locate its point of origin with an error margin of less than one percent.

    Drone testing demonstrated that, in both cases, the tracking and position data generated by the peripheral was closely correlated with what was provided by GPS. This supports the viability of using it for navigation in areas where GPS is not available, such as under a bridge or inside an industrial structure.

  • Abom launches military/industrial goggles with GNSS/INS

    Abom launches military/industrial goggles with GNSS/INS

    Logo: Abom

    Abom, a company that designs sophisticated commercial goggles, has launched new augmented reality (AR) goggles.

    Designed for safety, industrial and military markets, Abom’s P3 augmented reality goggles feature accurate tracking of orientation, velocity and positioning using IMU/GPS-GNSS/INS receiver capability.

    Other features include 3D spatial mapping and tracking, integrated VX Inc. CNED display technology, and an array of integrated image sensors and advanced embedded electronics. The goggles’ stereoscopic dual displays have an ultra-high-brightness output with adjustable control and 1080p output.

    The goggles are optimized with a military-ballistics-rated lens (MIL-PRF 32432A) that complies with the Military Compliance Eye Protection (MCEP) program, meeting many challenging elements of the U.S. Army’s IVAS specification (HUD 3.0).

    For industrial applications, the P3 also meets ANSI Z87.1+ high-mass impact rating and IP-55 ingress protection against water and dust, which opens the door for supporting National Safety Council technology initiatives and requirements for meeting extreme IP-67 rating compliance.

    The P3 goggles are field-use ready and designed for extreme environmental durability and cold-weather climate conditions where demanding ruggedized performance is critical. It has advanced thermal image sensors, and embedded within the Goggle Chassis is an ultra-high-performance depth camera supported by two infrared cameras optimized for low-light conditions up to 10 meters.

    The goggles incorporate Abom’s patented ultra-low power thin-film technology, making it impossible for fog to survive on the inner surface of the eyewear, according to the company.

    “Abom’s award-winning heated goggle technology, now military approved, has made integration and optimization with immersive, augmented reality display technology the perfect solution for highly ruggedized extreme use-cases that exceed industry standards for both quality and performance,” said Jack Cornelius, Abom CEO.

    “Abom’s development partner for the P3 Goggle, VX Inc., has pushed the limits of mechanical and electrical engineering design performance,” Cornelius said.

  • Inertial Sense presents full sensor fusion at Xponential 2019

    Inertial Sense CEO Brian Cahoon discusses the company’s product line at Xponential 2019, which took place April 29-May 2 in Chicago. A combination of the company’s inertial navigation sensors, IMU, GPS sensor and processor creates full sensor fusion, Cahoon said.

  • Using consumer-grade sensors for precise positioning

    By Urs Niesen, Jubin Jose, Xinzhou Wu, Qualcomm Technologies Inc.

    Emerging automotive applications require reliable but at the same time low-cost positioning solutions. In this paper, we present such a solution by fusing the measurements from several consumer-grade sensors using a tightly coupled centralized filter.

    The sensors used are a single-frequency GNSS receiver providing GPS and GLONASS pseudoranges and GPS carrier-phase measurements, a micro-electro-mechanical (MEMS) inertial measurement unit (IMU), a monocular camera, wheel-speed and steering-angle sensors.

    We also employ vehicular constraints, integrated as pseudo-measurements. The centralized fusion architecture allows sensor cross-calibration and improves outlier detection. The filter runs in real time on the target platform, producing pose estimates at 30 Hz. Through extensive experimental evaluations, we demonstrate positioning accuracies of sub-meter 95-percentile horizontal errors even in GNSS-challenged deep-urban scenarios.

    Conflicting Requirements. Accurate positioning is a requirement for several emerging vehicular applications such as advanced driver-assistance systems (ADAS) and autonomous driving. Positioning solutions for these applications face two competing constraints. To be technically viable, the computed position estimate needs to be reliable in scenarios ranging from open sky to deep urban, with less than 1-meter 95-percentile horizontal error as an often-mentioned target. To be economically viable, the system needs to be built from consumer-grade components.

    We reconcile these conflicting requirements by fusing measurements from several low-cost sensors into a single pose estimate using one centralized extended Kalman filter (EKF). A multi-constellation single-frequency GNSS receiver provides GPS pseudorange and carrier-phase measurements and GLONASS pseudorange measurements. These are combined in a tightly coupled integration architecture with a consumer-grade MEMS IMU used to produce the reference navigation solution.

    Tight integration enables outlier rejection directly for the raw GNSS measurements. This is crucial in deep-urban scenarios, since many or most raw GNSS measurements could be outliers in these conditions. We use a monocular camera and vehicular sensors, providing four wheel-speed measurements and a steering-angle measurement, as additional aiding sensors.

    Constraints. Finally, vehicular constraints are integrated as pseudo-measurements. These sensors have very different noise sources and failure modes, which allows cross-calibration and improves failure and outlier detection. Given the tightly coupled integration in a single EKF, the filter state is quite large and can reach more than 100 dimensions. Despite its size, we are able to run the filter in real time and on target, producing pose outputs at a rate of 30 Hz.

    We report the result of extensive experimental evaluations in different scenarios ranging from open sky with good satellite visibility to deep urban with long stretches of no or only limited satellite visibility. In each of these scenarios, we obtain the target accuracy of sub-meter 95% horizontal positioning error.

    We show that, in the benign open-sky scenarios, GPS and IMU sensors are sufficient to achieve the target accuracy. However, in challenging deep-urban scenarios, all the integrated sensors are required to attain reliable sub-meter positioning performance.

    Sensors and Components. We use Qualcomm SiRFstarV 5e B02 GNSS chipset, a low-cost commercial GNSS product, connected to a NovAtel GPS-702-GG dual-frequency GPS+GLONASS Pinwheel antenna, the only component not consumer-grade, to separate impact of a specific antenna on performance. We plan to evaluate low-cost antennas in the future. We use a TDK InvenSense low-cost MEMS 6-axis IMU (MPU-6150) and a vehicle interface with vehicle sensors through the controller area network bus. Accurate timestamping for tightly coupling sensor measurements is provided by a custom sensor sync board. The processor is a Qualcomm Snapdragon 820 automotive platform for real-time computation. (Qualcomm SiRFstar and Qualcomm Snapdragon are products of Qualcomm Technologies, Inc. and/or its subsidiaries.)

    This paper was presented at ION-GNSS+ 2018.
    .

  • Honeywell emphasizes ruggedized feature of IMU at Xponential 2019

    Honeywell emphasizes ruggedized feature of IMU at Xponential 2019

    Photo: HoneyWell
    Photo: HoneyWell

    Honeywell displayed its HG4930 MEMS-based inertial measurement unit (IMU) at Xponential 2019, which took place April 29-May 2 in Chicago.

    The company emphasized the IMU’s rugged design, which the company says allows the IMU to meet the needs of the most demanding users. The HG4930 also features gyroscopes, accelerometers and an internal environmental isolation system.

    Check out the video below, which showcases the HG4930 being treated as a hockey puck.

    According to Honeywell, the HG4930 can be used for applications in the agriculture, automotive, communication, construction, energy, inspection, mapping, marine, mining, robotics, surveillance and transportation industries.

  • KVH showcases IMUs at Ocean Business 2019

    KVH showcases IMUs at Ocean Business 2019

    Image: KVH
    The GEO-FOG 3D Dual inertial navigation system (INS) is designed for applications that require heading at system startup or in low dynamic conditions. (Image: KVH)

    KVH Industries will showcase its inertial products at Ocean Business 2019, taking place in Southampton, U.K., April 9-11.

    When GNSS is not an option, KVH’s Fiber Optic Gyro (FOG)-based IMUs and inertial navigation systems — the GEO-FOG 3D and 3D Dual — provide accurate and reliable navigation for manned and unmanned maritime and underwater systems, the company said.

    “When we compare the data and performance of the KVH 1750 IMU to comparable SWAPC components, we find a tremendous disparity in performance,” said Ben Kinnaman, CEO of Greensea Systems Inc. “The KVH 1750 IMU outperforms similar components and sensors in that category by orders of magnitude.”

    Visit KVH at Stand J8 and learn more about KVH’s FOG-based 1750 IMU, which is available with 2g accelerometers and designed specifically for subsea vehicle navigation and positioning.

     

  • Cooperative utility effort takes off with Topcon

    Cooperative utility effort takes off with Topcon

    Images: Topcon
    Images: Topcon

    An Arizona electric cooperative that serves more than 33,000 customers is helping prove the value and potential of unmanned aerial systems (UAS) in enhancing the utility’s geospatial information system (GIS) effort.

    Using an Intel Falcon 8+ Drone — Topcon Edition, UAS specialist Skynetwest is performing missions to illustrate the viability of UAS technology. Initial work for the Navopache Electric Cooperative (NEC) included inspection of a substation, conducted on a windy day that might have grounded traditional aircraft.

    Windspeed limits for the Falcon 8+ in GPS mode are set at 26 mph; in height mode that threshold is extended to windspeeds as high as 35 mph.

    Using ContextCapture and Agisoft PhotoScan software, Skynetwest created a detailed georeferenced 3D model of the substation.

    The Falcon 8+ also has triple-redundancy inertial measurement units (IMUs), double redundant compasses, dual-constellation GPS, eight propellers and two batteries. An algorithm selects the most accurate of the redundant systems to use when the UAS is flying near the electromagnetic frequencies emitted by power lines.

    The team easily switched between a camera payload for inspections and one for mapping. Skynetwest’s mapping package takes high-resolution geo-referenced aerial images from various heights within set GPS tolerances. Its RGB camera delivers both orthophotos and 3D models in Topcon ContextCapture software, powered by Bentley Systems.

  • SBG’s Horizon IMU equips for harsh-environment hydrography

    SBG’s Horizon IMU equips for harsh-environment hydrography

    The Horizon fiberoptic gyro (FOG) inertial measurement unit (IMU) now forms part of SBG Systems’ Navsight Marine Solution, dedicated to hydrographers. Navsight is available at different levels of accuracy to meet the various application requirements and can be connected to various external equipment such as echo-sounders, lidar, and so on.

    Photo: SBG Systems
    Photo: SBG Systems

    Navsight Marine Solution already offered two levels of performance with the Ekinox and Apogee IMUs. These MEMS-based IMUs address most of hydrographics markets whether shallow or deep water.

    The new Horizon IMU enables customers to deploy Navsight in the most demanding environments such as surveying highly dense areas (bridges, buildings, and so on) as well as applications where only a single antenna can be used.

    The Horizon IMU is based on a closed-loop FOG technology which enables ultra-low bias and noise levels. This technology allows robust and consistent performance even in low dynamics survey.

    Navsight solution is easy to install, as the sensor alignment and lever arms are automatically estimated and validated. Once connected to the Navsight processing unit, the web interface guides the user to configure the solution. A 3D view of the vessel shows the entered parameters so that the user can check the installation. The Navsight unit also integrates light emitting diode (LED) indicators for satellite availability, RTK corrections, and power. It comes with a rugged enclosure, or in a rack version for larger vessels.

    Completing the Navsight offer, Qinertia, SBG’s post-processing software, gives access to offline RTK corrections from more than 7,000 base stations located in 164 countries. Trajectory and orientation are then greatly improved by processing inertial data and raw GNSS observables in forward and backward directions. Computation takes less than 3 minutes for a 6-hour log thanks to the Forward and Backward calculation processed at the same time.

  • Research Roundup: Modeling lidar data for positioning

    By Daniela E. Sánchez, Harvey C. Gómez and Thomas Pany, Institute of Space Technology and Space Applications (ISTA)

    This paper presents how our system, consisting of a GNSS receiver antenna, an inertial measurement unit (IMU) and a lidar, is used to obtain high-precision maps through the geo-referencing of lidar point clouds. An accuracy assessment of the system is conducted, which also gives us insights on the quality of lidar range measurements for autonomous driving applications.

    The assessment is done by geo-referencing the obtained point clouds of extracted buildings and comparing them against a supporting measuring system like a total station. The building extraction is done by performing an approximation of the mathematical model of a plane to the facades that composes the building in both, the lidar and the supporting measurement system data.

    The paper also indicates the proposed pose determination method of a mobile agent using lidar data. Thanks to the advantages of active, 3D sensors, diverse objects in the environment can be detected as individual point sets, or clusters. Each of the segmented objects can be used as a landmark to figure how the agent is located with respect to those structural elements. The algorithm is capable of detecting the clusters in one point cloud, and finding the most alike point set on a subsequent scan. This is achieved by comparing global descriptors for point cloud data.

    The Ensemble of Shape Functions (ESF) is selected as the cluster descriptor. The cluster matching is performed by comparing the clusters one-to-one, calculating the minimum Chi-squared distance among their descriptors. The smaller this distance, the greater the probability of being the same cluster in distinct epochs.

    Figure 2. Direct geo-referencing of lidar data at different times. (Image: Authors)
    Figure 2. Direct geo-referencing of lidar data at different times. (Image: Authors)

    The resultant cluster correspondences for the whole point cloud allow finding the rigid transformation between the point clouds. An initial coarse alignment among the clouds based on the centroids of each matched cluster was performed, followed by a fine alignment in order to reduce errors by the use of the Iterative Closest Point (ICP) algorithm. This approach is valid for urban environments, or for those where many objects can be segmented as clusters.

    Finally, a practical case is described in order to show how we plan to use the outcome of the highly precise geo-referenced point clouds and the pose estimation method using lidar.

    More info at www.ion.org/publications/ browse.cfm.

  • Horizon IMU adds choice to SBG’s Navsight Land/Air Solution

    Horizon IMU adds choice to SBG’s Navsight Land/Air Solution

    Photo: SBG Systems
    Photo: SBG Systems

    SBG Systems has released the Horizon IMU, a FOG-based high performance inertial measurement unit (IMU) designed for highly demanding surveying applications such as high-altitude data collection or mobile mapping in dense areas such as urban canyons.

    SBG Systems made the announcement at the International LiDAR Mapping Forum (ILMF) in Denver.

    The Horizon IMU joins the Ekinox and Apogee IMUs as options for the Navsight Land/Air Solution. The solution consists of a powerful and ready-to-use inertial navigation solution dedicated to surveyors for mobile data collection.

    The new Horizon IMU allows customers to bring the Navsight technology to the most demanding environments such as high-altitude surveying and highly dense areas, as well as application where only a single antenna can be used.

    The different levels of accuracy enable the solution to meet various application requirements and can be connected to various external equipment such as odometer, lidar and more. The Ekinox and Apogee MEMS-based IMUs address most surveying markets for camera or lidar motion compensation and data geo-referencing.

    The Horizon IMU is based on a closed-loop FOG technology which enables ultra-low bias and noise levels. This technology allows robust and consistent performance even in low dynamics survey.

    The Navsight solution is easy to install in a vehicle — the sensor alignment and lever arms are automatically estimated and validated. Once connected to the Navsight processing unit, the web interface guides the user to configure the solution.

    A 3D view of the vehicle shows the entered parameters so that the user can check the installation. By choosing the vehicle — a plane or a car, for example — the inner algorithms are automatically adjusted to the application.

    The Navsight unit also integrates LED indicators for satellite availability, real-time kinematic (RTK) corrections and power.

    Full INS/GNSS Post-Processing Software

    Completing the Navsight offer, Qinertia, the SBG post-processing software, gives access to offline RTK corrections from more than 7,000 base stations in 164 countries. The software delivers the highest level of accuracy without having to set up a base station. Trajectory and orientation are then greatly improved by processing inertial data and raw GNSS observables in forward and backward directions.

    Navsight is ITAR-free. All models are available for order. Ordering information and delivery time are available from SBG Systems representatives and authorized SBG Systems dealers.

  • CHC Navigation unveils Alpha3D mobile mapping solution at Intergeo 2018

    CHC Navigation debuted its new Alpha3D mobile mapping solution at Intergeo 2018, which took place Oct. 16-18 in Frankfurt, Germany. Alpha3D combines a laser scanner, high-resolution HDR panoramic camera, GNSS receiver and high precision IMU.