Autonomous Flying

Applications
Title	Autonomous Flying
Author(s)	GMV.
Level	Medium
Year of Publication	2011

Advanced UAVs (Unmanned Aerial Vehicles) are used or proposed in many missions covering security (including border patrol, anti-drug warfare, chemical, biological and radiological detection, maritime vessel identification and interdiction), surveillance of infrastructures (pipelines, power lines, railways, waterways, roads, airports), search and rescue, mapping, fisheries, agriculture, forestry, natural resource monitoring, fire fighting and emergency management, airborne communication collection and relay, weather data collection, environmental monitoring, pollution detection and other scientific research.

GNSS plays a very important role in UAVs. Either in when guided autonomously or guided by ground-based pilots GNSS is used for determination of the location and speed of the UAV either for navigation or georeferencing the collected data. If the vehicle is autonomous GNSS can contribute actively to the control loop of the UAV by providing inputs to the control algorithm and by given feedback to the control algorithm after an action is taken.

Application Architecture

In UAVs, GNSS can be used for 4 different types of applications:

• Navigation - The use of GNSS in the navigation of UAV is similar to the use in manned aerial vehicle navigation. Two main differences can be observed:
  • Safety requirements are less stringent since the loss of the vehicle doesn't imply the loss of human lives or injuries. Anyhow safety must be taken into account as described below.
  • In autonomous UAVs, GNSS is part of the control loop of the guidance algorithm, although other sources such as cameras, inertial sensors are normally used and combined by filters with GNSS data to guide the vehicle.
• Attitude Determination - Attitude determination can be used by UAVs in the same way as in manned aerial vehicle attitude determination
• Georeferencing data - As described, UAVs can be used for a numerous type of activities. The main type of payload is earth observation payload where different techniques (cameras, radars, lidars,...) are used to monitor or collect information from the earth surface. For this information to be useful needs to be georeferenced and this is normally done using GNSS.
• Safety - Although self-preservation is less relevant in an unmaned aerial vehicle is still very important that UAVs don't interfere with maned planes and that don't cause loss of lives or property damage when they land or crash. Therefore