High payload unmanned aerial vehicle for agricultural spraying

Abstract

In the last decades, with the emergence of GPS navigation and advanced avionics for aircraft, the precision and efficiency of aerial spraying have improved, however all still remain within pilots´ manual control precision limits of the flight and the sprayer. Moreover, costs and risks of aerial spraying have sustained due to the high speed and low altitude nature of the operation. In 1997, Japan introduced the Yamaha RMAX, an R/C Helicopter for agricultural spraying, that eliminated the onboard pilot, improving spraying precision drastically while reducing costs and risks. However, R/C helicopters for agricultural use did not see substantial acceptance due to their low payload capacity, still substantial acquisition and maintenance costs, and safety issues. In the last decade, multi-rotor drones have emerged as alternatives, addressing some of these shortcomings. While multi-rotors are simpler to use, their low-aspect ratio propellers, frequent rotor speed adjustments for vehicle stability, and non-aerodynamic frames result in extremely low flight efficiencies and ranges. Current commercial offerings can carry payloads between 25L of product and have flight durations in the order of 10 minutes. Recognizing the benefits and short-comings of multi-rotor drones and helicopters, we propose to introduce a highly efficient fixed-wing UAV (Unmanned Aerial Vehicle) specialized for agricultural spraying. Our proprietary design is ~10 times more efficient in flight than the best multi-rotors in the market. It incorporates STOVL (Short Take Off, Vertical Landing), VTOL (Vertical Take Off & Landing) and CTOL (Conventional Take-off & Landing) capabilities that allow for the user to adapt and optimize the payload according to the conditions of the land and airfield space. Through the past 3 years, AgroBotz team dedicated resources, expertise in aerodynamics, computational fluid dynamics, flight simulation software, scientific computing, and CNC to prototype and deliver a functional UAV prototype. We are currently in the flight-testing stage of the 2nd prototype with promising results. In order to bring a competitive product to the market, we need resources to deliver on several technical advancements, and the proposed work in this project involves:1. incorporating the hardware and flight control software for robust CTOL, STOVL and VTOL operations; 2. incorporating professional spraying equipment to validate spraying efficiency on select cultures; 3. developing collision avoidance electronics and algorithms, 4. developing detailed engineering design and infrastructure for the production of Class 2 product (larger than current prototype) for its commercial entry into the market. Market analysis shows that the proposed value proposition and business model are attractive for both aerial spraying service companies and farmers that operate their own sprayer aircraft. In addition, reduction of pesticide use with precise and targeted spraying will reduce environmental and health hazards of today's handheld or high-volume aerial spraying operations. The integration of the underlying technologies into a reliable UAV design for agricultural spraying, compliant with evolving legislation is a serious undertaking that requires continuous research, development and detailed engineering. We also envision that each situation (farmland area, terrain and weather conditions, grown culture and its threats) will present itself with the challenge of finding a balance among factors such as sprayed liquid and flight battery payload capacities, usage simplicity and safety, spraying precision and overall product and operational cost. Beyond technology, resources will need to be devoted to market research to prospect partners and investors in order to evolve the project into a serious services and manufacturing business. (AU)