Issue 40 Unmanned Systems Technology October/November 2021 ANYbotics ANYmal D l AI systems focus l Aquatic Drones Phoenix 5 l Space vehicles insight l Sky Eye Rapier X-25 l FlyingBasket FB3 l GCS focus l AUVSI Xponential 2021

12 Spirent Communications has developed a cloud-based system that can predict where and when unmanned vehicles, air taxis and UAVs can operate BVLOS safely and dependably using satellite data (writes Nick Flaherty). The Spirent GNSS Foresight service is the first of its kind, and addresses a key issue facing developers and operators of UAVs and autonomous vehicles. Because GNSS performance can be unpredictable in urban and suburban areas, owing to signals being obscured or blocked by buildings, autonomous systems have not been able to rely on GNSS for accurate positioning. GNSS Foresight uses high-definition maps and precision orbital modelling to give a clear picture of the operating environment. It calculates GNSS availability for every metre, every second, from an altitude of 1 to 100 m and for up to 3 days into the future. A risk analysis tool aggregates GNSS forecasts to provide best-case, worst- case and 90th percentile predictions in a specified area. This is provided as real- time data via an API or as a heat map, analysis and a report. GNSS Foresight overcomes navigation and positioning challenges by providing real-world situational awareness ahead of time to improve pre-flight or real-time performance, through a cloud-based service. It can be used to determine areas that are always safe to fly or operate in, in addition to finding the exact time in a degraded area that specific operational requirements can be met.  This allows operators to increase operational areas, reducing the number of system disengagements and providing greater safety and reliability when removing human involvement in the driving or piloting task. Using multiple signals from the GPS, GLONASS, Galileo and BeiDou satnav systems can greatly improve signal reception in urban and suburban environments, but there are still areas where sometimes not enough satellites are in view to calculate an accurate position. For example, a street corner that has poor GNSS reception at 3pm may be perfectly navigable again just 10 minutes later, so a static map would be inaccurate and misleading. A dynamic map accurately forecasts changing patterns along alternative routes, giving a vehicle the situational awareness to decide which route to take. The system also has to include altitude consideration for UAVs. The higher they fly, the more likely they are to have line of sight to four or more satellites, greatly reducing the problem of signal loss. But that means trade-offs in terms of energy consumption and how much a UAV can carry. Higher altitudes might also be reserved for other airspace users such as air taxis and manned aircraft. Traffic forecasts in the cloud Airborne vehicles October/November 2021 | Unmanned Systems Technology The forecasting service can deliver real-time data on the availability of satellite navigation data as a heat map