Use of Quadcopter Wakes to Supplement Strawberry Pollination

TL;DR

This study addresses pollination shortfalls in strawberries by exploring a drone-based, wind-assisted pollination approach that leverages quadcopter downdrafts to transfer pollen. It combines lab experiments using Holi powder with a field trial on a Malwina strawberry row, analyzed via linear mixed models and computer-vision berry metrics. Lab results indicate that quadcopter wakes can move pollen-sized particles and that optimized height and hover patterns may enhance transfer, guiding field design, while field results were inconclusive, underscoring real-world complexities. The work demonstrates a low-cost, scalable direction for augmenting pollination and prompts further refinement of downdraft physics, flight protocols, and isolation methods to enable practical farm deployment.

Abstract

Pollinators are critical to the world's ecosystems and food supply, yet recent studies have found pollination shortfalls in several crops, including strawberry. This is troubling because wild and managed pollinators are currently experiencing declines. One possibility is to try and provide supplemental pollination solutions. These solutions should be affordable and simple for farmers to implement if their use is to be widespread; quadcopters are a great example, already used for monitoring on many farms. This paper investigates a new method for artificial pollination based on wind pollination that bears further investigation. After determining the height where the lateral flow is maximized, we performed field experiments with a quadcopter assisting natural pollinators. Although our results in the field were inconclusive, lab studies show that the idea shows promise and could be adapted for better field results.

Figures (7)

• Figure 1: A) pollen from the anther (part of the stamen) is transferred to the stigma (part of the pistil), which then develop flesh around them and become achenes. The more achenes are pollinated, the heavier and more shapely the fruit will be; B) example of how the quadcopter's downdraft that potentially could be a mechanism to transfer the pollen.
• Figure 2: A) Setup to investigate the effects of height on pollen transfer with tape on the pole indicating the experimental height; B) Setup to investigate the effects of flight pattern on pollen transfer (the height marker was also used but remained at the same height); C) an example of what the simulated pollen looked like on the glass slide.
• Figure 3: Box and whisker plots with data overlaid for the first experiment investigating the effects of height on pollen transfer A) Holi powder loss mass measurements and B) Holi powder transfer as number of particles
• Figure 4: Box and whisker plots with data overlaid for the experiment investigating the effects of flight pattern on pollen transfer. A) simulated pollen loss mass measurements and B) simulated pollen transfer as number of particles.
• Figure 5: A) Color-coded key showing which plants in the row of the field experiment were randomly assigned to which control groups; B) Example of the field setup and hardware used on any given day for the field experiment.