How does it work?
Drone software, Swiss made The PX4 operating system has been widely adopted by open source-based drones. Next step: incorporating vision. Journalist: Daniel Saraga Infografic: ikonaut
The brain Developed at ETH Zurich, the open-source platform PX4 works like the operating system of a smartphone. It controls the propellers, feeds off information from the sensors and allows for the integration of additional m odules. An autopilot enables the drone to reach a destination automatically or hover steadily on the spot.
The ears A drone uses a variety of devices to calculate its position and direction. The GPS gets signals from satellites; they are robust but not very precise or fast. The inertial sensors measure the accumulated movements after take-off. Laser or ultrasound altimeters give the elevation. In special indoor settings, fixed external infrared cameras triangulate the position of markers on the drone.
The limbs Apps can also be added – third-party software designed for a specific task. A ‘follow-me’ app developed in Latvia instructs the drone to hover at a certain distance above a GPS receiver worn by the user. This service was offered to skiers in Swiss resorts last winter. Other researchers have used PX4 to control juggling drones or vertical landing planes.
The eyes Computer vision is not yet widely used on commercial drones. Aerial robots from labs at ETH Zurich were the first to fly using on-board cameras only. They can reconstruct the shape and dimensions of objects. “Vision allows the drone to recognise obstacles and avoid them. It’s necessary for safety”, says Lorenz Meier, a PhD student and the author of the PX4 operating system. “We will incorporate computer vision in 2016 by default in PX4- driven drones”. He has also developed Pixhawk, a hardware autopilot running PX4.
Swiss National Science Foundation – Swiss Academies: Horizons No. 109
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