‘UAV-based remote sensing will be like using a cell phone today’
How does UAV technology contribute to agriculture?
Reliable agricultural statistics are one of the main bottlenecks in today´s agriculture. Remote sensing in general can be used for discriminating crops and estimating acreage. Notwithstanding, costs per scene and the presence of clouds preclude its widespread use. The new generation of satellites e.g. Sentinel 1 & 2 and Sentinel 3, which is scheduled to be launched by the European Space Agency in 2022, will provide affordable imageries for agricultural applications. That leaves the clouds as probably the main limiting factor especially under rain-fed conditions. We have tried getting imageries for the potato growing areas in Uganda and Ethiopia and could not get a single scene with less than 10% cloud cover throughout the entire growing period. Remote sensing platforms able to register scenes over agricultural fields under the clouds are a must have. With the spatial resolution attained with unmanned aerial vehicles (UAV) based remote sensing, crop discrimination is feasible even with conventional RGB (red, green, blue) cameras. With spatial resolution of less than 10 centimetres, processing imageries to facilitate decisions for precision agriculture is highly feasible. Early warning and yield forecasting systems are no longer science fiction with today’s UAV technology.
From your answer we understand that the technology can be easily adopted by large scale farmers. How would small scale farmers benefit from it?
Smallholder farmers are not expected to be direct users of this technology right away but in less than ten years – my guestimate – farmers will be so permeated by ICT technology that the use of UAV-based remote sensing will be like using a cell phone today. Meanwhile, we need to re-tool government agencies, agriculture-oriented NGOs, and farmers’ associations. Moreover, young professionals in physics, electronics and agriculture could become entrepreneurs and provide the service needed in rural areas. The Bureau of Statistics within the Peruvian Ministry of Agriculture is requesting CIP to provide training and backstopping to modernise their agricultural census with the use of UAV-based remote sensing. Negotiations are under way with other countries in Africa and Asia as well.
Most UAVs used for civil purposes are manufactured in China, the US and Europe. What are your thoughts on producing or assembling UAVs in Africa, as an example?
First of all, UAV-based remote sensing platforms have at least three key components: the vehicle (the UAV itself); the sensor; and the support interface frame that allows communication with both the radio control and the telemetry from the UAV’s control unit. Most people concentrate on the UAV. For an agriculturalist this is probably the least significant component of the platform. One of the reasons is that China, US, and Europe can provide this component at very competitive prices. The problem is when intermediaries in developing countries sell those, otherwise low-cost UAVs, at very high prices. Notwithstanding, UAVs can be locally built. Our partner at University of Nairobi has built a tetracopter using ardu-pilot technology with great results. They have also assembled multi-rotors with importing parts. They have also fixed the UAV after crashes in the field. Therefore, local professionals can assemble or produce UAVs in-situ, depending on the needs. The most critical component is the sensor. Most users buy integrated solutions. This is a good starting point but in our experience not always the most convenient. These products, by definition are “black boxes” and thus the user is limited to whatever the vendor defines as the “best” solution for agricultural applications. When you build your own sensors you have total control of the product and have access to the raw data. You can improve your signal to noise ratio and thus generate better imageries. The interface is very important since you want to be able to use the telemetry from the UAV for the processing of the imageries. A must have is open access software for mosaicking, and some of the pre-processing required to generate the data needed for agricultural analyses. CIP has developed open access software that UAV-users are welcomed to download and use.
What role could governments and development agencies play in facilitating the adoption of the technology in Africa and small islands developing states?
First of all, by making user friendly and forward looking policies e.g. in Peru the proposed legislation pretends to limit flying altitude to 150 metres. Flying fix-wing UAVs at this altitude make no sense for agricultural applications. In the second place, fostering capacity building in developing countries. In third place, modernising the bureaus of statistics and the likes with UAV technologies focusing on open access solutions to guarantee its sustainability.
Roberto A. Quiroz (email@example.com) is a biophysical scientist at the International Potato Center (CIP) based in Lima, Peru. There he leads a multidisciplinary team on methods and tools to assess the impact of climate variability and change on agriculture and the feedback of agricultural practices to the environment. He was born in Panama.