Satellite images have been used to support humanitarian efforts for decades. Why? A bird’s eye view of a disaster-affected area simply captures far more information than most Earth-based data-collection technologies can. In short, birds have more situational awareness than we do. In contrast to satellites, UAVs offer significantly higher-resolution imagery, are unobstructed by clouds, can be captured more quickly, by more groups and more often at a fraction of the cost with far fewer licensing and data-sharing restrictions than satellite imagery.
Introduction to UAVs
There are basically three types of UAVs: 1) the balloon/kite variety; 2) fixed-wing UAVs; 3) rotary-wing UAVs. While my forthcoming book looks at humanitarian applications of each type, I’ll focus on fixed-wing and rotary-wing UAVs here since these are of greatest interest to humanitarian organizations. These types of UAVs differ from traditional remote control planes and helicopters because they are programmable and intelligent. UAVs can be programmed to take-off, fly and land completely autonomously, for example. They often include intelligent flight stabilization features that adapt for changing wind speeds and other weather-related conditions. They also have a number of built-in fail-safe mechanisms; some of the newer UAVs even include automated collision avoidance systems.
Fixed-wing UAVs like senseFly’s eBees (above) are launched by hand and can land a wide variety of surfaces, requiring only a few meters of landing space. They fly autonomously along pre-programmed routes and also land themselves auto-matically. My colleague Adam from senseFly recently flew eBees to support recovery efforts in the Philippines following Typhoon Yolanda. Adam is also on the Advisory Board of the Humanitarian UAV Network (UAViators). Other fixed-wing UAVs are flown manually and require an airstrip for both manual take-off and landing. Rotary-wing UAVs, in contrast, are “helicopters” with three or more propellors. Quadcopters, for example, have four propellors, like the Huginn X1 below, which my colleague Liam Dawson, another Advisory Board member, flew following Typhoon Yolanda in the Philippines. One advantage of rotary-UAVs is that they take-off and land vertically. They can also hover in one fixed place and can also be programmed to fly over designated points.
Rotary-UAVs cannot glide like their fixed-wing counterparts, which means their batteries get used up fairly quickly. So they can’t stay airborne for very long (~25 minutes, 2 kilometer range, depending on the model) compared to fixed-wing UAVs like the eBee (~45 minutes, 3 kilometers). Advisory Board member Shane Coughlan is designing fixed-wing humanitarian UAVs that will have a range of several hundred kilometers. Fixed-wing UAVs, however, cannot hover in one place over time. So both types of UAVs come with their advantages and disadvantages. Most UAV experts agree that fixed-wing and rotary-wing UAVs can serve complementary purposes, however. You can quickly use a quadcopter to an initial aerial recon and then send a fixed-wing UAV for more detailed, high-resolution imagery capture.