The Lake Doctors, Inc.

In this article, we’d like to introduce you to a new and useful tool the UPL NA Inc (UPL) Aquatics Team has been working on for managing aquatic plants and algae. It’s an autonomous aquatic drone boat! For the last few years, we’ve presented general updates and most recently brought an actual field-tested model to aquatic plant management conferences. We’re excited to share some details about the boat’s development to date, specific features of the boat, and welcome your interest in future testing and possible purchase. Almost everyone—especially those in the aquatics industry—is trying to do more with less, and there is a significant need to be more efficient. Technology is changing at a rapid pace to help save time and make tasks easier thereby increasing our efficiency and improving life in general. With that in mind, UPL has collaborated [1]rated with North Carolina State University (NCSU) since 2016 on the development of an autonomous drone spray boat named ADAPT™ (Aquatic Delivery Autonomous Precision Technology). The driving force behind the project was to offer a versatile, easy-to-use, pesticide delivery method that significantly reduced the exposure potential to the aquatic applicator. When the partnership between UPL and NCSU (Crop Science and Mechanical and Aerospace Engineering departments) began on developing the ADAPT™ spray boat, a provisional patent along with initial boat design was filed and project implementation began (Fig 1). The rather rudimentary boat had no chemical tank and was propelled by a small fan. Initial tests were promising; however, there was a problem with the boat tracking off-course in moderate winds. By the third generation (Fig 2), the previous tracking issues were resolved by replacing the fan propulsion with a lower power (~50# thrust) trolling motor, and the boat was lengthened by several feet to make room for a 10-gallon spray tank. Several trials were conducted with this iteration—including a full-scale treatment of roughly a quarter-acre pond for watermeal/duckweed—and resulted in excellent control (Fig 3). The next step in the evolution came with a manufacturing agreement with RMD Systems (San Luis Obispo, CA) in 2019 which significantly added more capabilities and capacity to the boats. By using many off-the-shelf parts, we are able to keep the cost down, while also offering a great deal of versatility. This allows the boat set up to be designed for an applicator’s specific needs. The current generation ADAPT™ spray boat has the following specifications and capacities (Table 1) in addition to the autonomous mode feature. A predefined track can easily be created and stored in the boat’s onboard memory, allowing the boat to automatically run the track in autonomous mode when directed by the applicator. An enhanced feature of autono[1]mous mode is the ability of the applicator to set specific waypoints to turn on and off the spray pump.

 

 

Figure 1. ADAPT™ 1st Generation
Figure 1. ADAPT™ 1st Generation

ADAPT™ 3rd Generation
Figure 2. ADAPT™ 3rd Generation

ADAPT™ Generation treating watermeal/duckweed
Figure 3. ADAPT™ Generation treating watermeal/duckweed

ADAPT™ Smart controller with integrated video display
Figure 4. ADAPT™ Smart controller with integrated video display

Table 1. ADAPT™ spray boat physical specifications and capacities.
Table 1. ADAPT™ spray boat physical specifications and capacities.

 

ADAPT™ is equipped with several safety features including a first-person, real-time video camera mounted on the bow which transmits a video feed to the applicator on the smart controller (Fig 4). Redundant GPS receivers, inertia meters, and compasses significantly reduce the pos[1]sibility of a “fail-to-run” situation. The boats have software that returns the vessels to the original launch point (also known as the “return to home” feature) when the batter[1]ies are running low or a loss of signal from the controller is detected. Lastly, ADAPT™ is equipped with LiDAR (light detection and ranging) sensors on the bow to stop the boat while running in autonomous mode when an obstacle is detected. Recently, UPL placed 3 boats in the hands of professional applicators for real[1]world testing to receive feedback on the current utility of the platform and evaluate potential changes to make it more useful. Particularly noteworthy was a trial conducted by The Lake Doctors, Inc (hereafter TLD). In May of 2021, TLD staff from the Jacksonville office and regional manager Sean Fleming simultaneously conducted an algae application and mapped a two-acre pond for bathymetry and sub[1]mersed aquatic vegetation using an ADAPT™ boat w hi le in autonomous mode. The mapping effort was repeated twice while on-site to document the accuracy of the guidance system. As you can see by the tracks in Fig 5, the boat maintained a very accurate path as evidenced by the overlayed image of the two tracks. Another evaluation was also performed to compare the ADAPT™ mapping accuracy to a typical application surveying vessel (i.e., johnboat operator-driven) used by TLD. The results were very comparable, ~75% similarity between methods to collect the data. It was noted that the accuracy rate would be higher if the transducer on the ADAPT™ was calibrated (position of the transducer relative to the water’s surface). Both trials were performed relatively quickly for the size of the pond evaluated. The ADAPT™ platform is tailored for multitasking as demonstrated in this trial that was completed in 25 minutes. Sean stated several key findings in the conclusion of his report. “Running in autonomous mode may allow for placement in difficult to access locations for treatment or bathymetric analysis. The autonomous mode would allow for precision treatments at specific areas of a waterway with confidence that the pathways would be followed. This would be most beneficial in developing tracks based upon biovolume maps generated. In such applications, the initial scan would flag the areas of greatest biovolume accumulation (Fig 6) and the subsequent runs would be able to precisely target those areas based upon GPS data rather than a visual line of sight. This would be particularly effective for areas of underwater vegetation deep in the water column. The trailing hoses can be set to the precise depth based upon the contour measurements to more precisely deliver herbicide to the target species.”

C-Map BioBase tracks and bathymetry output as collected by ADAPT™.
Figure 5. C-Map BioBase tracks and bathymetry output as collected by ADAPT™.

C-Map BioBase vegetation heat map and bathymetry output as collected by ADAPT™.
Figure 6. C-Map BioBase vegetation heat map and bathymetry output as collected by ADAPT™.

Figure 7. ADAPT™ drone boat at UF IFAS Aquatic Control Short Course August 2021
Figure 7. ADAPT™ drone boat at UF IFAS Aquatic Control Short Course August 2021

The latest generation ADAPT™ boats are back from testing with applicators and will be showcased at upcoming aquatic weed management conferences (Fig 7). They are also available for on-water demonstrations with prospective customers. Please contact your UPL sales representative to schedule a demonstration and discuss the personalization of a boat for your operational needs. UPL is proud to announce ADAPT™ is now available on the commercial market.

Dr. Justin Nawrocki ([email protected]) is the east coast, including Florida, territory sales manager for UPL. Justin has been a part of this drone boat development since the inception of the project while he was still a graduate student at North Carolina State University. He has moved up through the aquatics industry over the past 20 years from a professional applicator to an extension specialist for Lake Gaston to receiving his master’s and doctorate degrees from NC State researching aquatic plant management. Jacob Meganck (Jacob.meganck@upl-ltd. com) is the Midwest territory manager for UPL. Jacob started in the Aquatics industry in 2005 working for a major distributor and in 2011 moved into his role as Midwest territory manager. In the distribution role, he assisted in developing a speed-rate controlled application boat modified from agriculture and right-of-way systems. Jacob came onboard to the aquatic drone boat project when UPL partnered with NC State. Dean Jones ([email protected]) is the Mid-south territory manager for UPL. Dean has 25 years of experience in the aquatic plant management industry including serving as Manager of the Polk County Aquatic Weed Control Section, Senior Biological Scientist with Osceola County and the University of Florida Center for Aquatic and Invasive Plants, and a contractor for the US Army Corps of Engineers Engineer Research and Development Center. Dean became a member of the drone boat project team in January 2020 upon joining UPL.