Vision-based adaptive variable rate spraying approach for unmanned aerial vehicles

Abstract

The rapid developments of unmanned aerial vehicles (UAV) and vision sensor are contributing a great reformation in precision agriculture. Farmers can fly their UAV spraying pesticides around their crop fields while staying at their remote control room or any place that is separated from their farm land. However, there is a common phenomenon in rice planting management stage that some empty areas are randomly located in farmland. Therefore, a critical problem is that the waste of pesticides that occurs when spraying pesticides over rice fields with empty areas by using the common UAV, because it is difficult to control the flow accuracy based on the empty areas changing. To tackle this problem, a novel vision-based spraying system was proposed that can identify empty areas automatically while spraying a precise amount of pesticides on the target regions. By this approach, the image was preprocessed with the Lucy-Richardson algorithm, then the target area was split from the background with k-means and the feature parameters were extracted, finally the feature parameters were filtered out with a positive contribution which would serve as the input parameters of the support vector machine (SVM) to identify the target area. Also a fuzzy control model was analyzed and exerted to compensate the nonlinearity and hysteresis of the variable rate spraying system. Experimental results proved that the approach was applicable to reducing the amount of pesticides during UAV spraying, which can provide a reference for precision agriculture aviation in the future.

Research on Methods Decreasing Pesticide Waste Based on Plant Protection Unmanned Aerial Vehicles: A Review

“… Wen et al (2018) proposed a variable spray system based on a PID and PWM, using the prescription map from ArcMap software to guide the variable spray system to work according to the prescription map. Wang et al (2019c) used the Lucy-Richardson algorithm to segment the open space and the vegetation area. When the spraying system is in the open space, the system will stop spraying.…”

“…Wen et al (2018) proposed a variable spray system based on a PID and PWM, using the prescription map from ArcMap software to guide the variable spray system to work according to the prescription map. Wang et al (2019c) (2020a) used UAVs for weed mapping and specific location management (UAV-IS), spraying weeds at specific locations to reduce the use of pesticides. Ex-Green and Ex-Red methods were also performed for the construction of the rice canopy model (Hong et al, 2020).…”

Design of Variable Spray System for Plant Protection UAV Based on CFD Simulation and Regression Analysis

“…At the software level, the main reference factor is the standard for determining the dosage. Hong et al achieved a variable spray system for rice canopy coverage [53], Hunter et al obtained the weedy area [54], and Wang et al aimed to avoid planting areas without crops [55]. Wen et al designed a variable spray system based on wind tunnel test data and neural network model [49].…”

“…obtained the weedy area [ 54 ], and Wang et al. aimed to avoid planting areas without crops [ 55 ]. Wen et al.…”

Analysis of the Influence of Parameters of a Spraying System Designed for UAV Application on the Spraying Quality Based on Box–Behnken Response Surface Method

“…Faiçal et al [17] introduced a series of optimization algorithms, such as genetic algorithm, particle swarm algorithm, and hill-climbing algorithm, to optimize the UAV's flight route according to the dynamically changing weather conditions. Variable-rate application is another adaptive approach to achieve area-even spraying [18][19][20]. Wang et al [21] realized the dynamic adjustment of flow rate following the real-time change of flight speed and improved the uniformity of the deposition distribution.…”