15 Sep 2021

Field Evaluation of GNSS/GPS Based RTK, RTN, and RTX Correction Systems

Abstract: This Coastal and Hydraulic Engineering Technical Note (CHETN) details an evaluation of three Global Navigation Satellite System (GNSS)/Global Positioning System (GPS) real-time correction methods capable of providing centimeter-level positioning. Internet and satellite-delivered correction systems, Real Time Network (RTN) and Real Time eXtended (RTX), respectively, are compared to a traditional ground-based two-way radio transmission correction system, generally referred to as Local RTK, or simply RTK. Results from this study will provide prospective users background information on each of these positioning systems and comparisons of their respective accuracies during in field operations.

1 Oct 2020

Electronic Railroad Inspection Database System for Military Facilities

Abstract: The U.S. Army Engineer Research and Development Center (ERDC) executes inspection programs as part of the U.S. Army Transportation Infrastructure Inspection Program (ATIIP). These inspections, monitoring, and assessment programs include airfields, bridges, dams, railroads, waterfront facilities, and ranges. To date, the process for these inspection programs has been manually intensive, time consuming, and difficult to scale. The ERDC is bringing digital business and spatial data collection methods to its inspection program for the military’s railroad infrastructure. By combining GPS and GIS technologies into a mobile data collection solution, added efficiency and data quality have been brought to the field inspection workflow. This modernization effort also results in streamlined data processing and reporting. These improved processes will lead to higher quality data, better analysis of the new richer data content, and better decisions made by the end-users and stakeholders.

1 Sep 2020

PUBLICATION NOTICE: Sensor and Environment Physics in the Virtual Autonomous Navigation Environment (VANE)

Abstract: This report documents the physics models that are implemented in the Virtual Autonomous Navigation Environment (VANE), a sensor simulator that uses physics-based ray tracing to simulate common robotic sensors such as cameras, LiDAR, GPS, and automotive RADAR. The report will provide information about the underlying assumptions and implementation details regarding the physics models used in VANE simulations. These include surface reflectance and texture models, atmospheric models, weather effects, and sensor properties. The purpose of this report is to provide information for VANE users, developers, and analysts who would like to use the VANE for sensor simulations.

9 Jul 2020

PUBLICATION NOTICE: Spatiotemporally coherent tensor decompositions for the analysis of trajectory data By Trevor Ruiz and Charlotte Ellison

Abstract: Location acquisition technologies such as global positioning systems (GPS) sensors or telemetry devices generate abundant spatiotemporal measurements of movement of people, animals, and vehicles. The resultant data represent trajectories-paths in space and time traversed by moving objects- and can often be merged with additional information about the entities in motion from connected or external data sources (Zheng 2015). New data analysis frameworks may be able to uncover patterns of human behavior from the fused trajectory and contextual i information. This data and new insights gained from novel analysis tools are p potentially of great interest to the Army and the geospatial community.