Phenocopter: Utilising a Robotic Helicopter to Phenotype Breeding Trials for Canopy Cover and Temperature.

Plant breeding trials are frequently extensive in size and therefore are expensive to monitor by conventional means, especially where measurements are time-sensitive. For example, when using a land-based measure of canopy temperature (hand-held infra-red thermometer), the atmospheric conditions can change greatly during the minutes to hours required to measure a trial. Another challenge in using image-based methods is to measure entire plots efficiently, rather than 'sampling' small areas. A high aerial position can assist in both of these issues by allowing rapid measurement of large numbers of plots, but the height needs to be low enough (10 to 40m) and the flight slow enough to precisely collect high-resolution images. This objective requires suitable hardware and software to plan flights and to extract and process the images. We will descibe the implementation of two robotic helicopters (a gas-powered 'hobby' craft with 5 kg payload and an electric quadcopter with 0.5kg payload) with custom-built autonomony that we use to take images of breeding and agronomy trials in wheat, cotton, sorghum, and sugarcane.