ROVs are important tools for marine pest surveillance programs. In this report, the author explores observation-class ROVs and explores how they could be further adapted for surveillance tasks.
Abstract: A review of observation-class ROVs suitable for marine pest surveillance purposes. Invasive marine species have potential to cause significant ecological and economic impact, however eradication is challenging and rarely successful. Control must therefore rely on effective management of introduction pathways and early detection. A key focus of Australia’s MarinePestPlan 2018–2023 and the supporting National Marine Pest Surveillance Strategy is identifying methods that enable cost-effective surveillance of vessels, infrastructure and marine environments. Over recent years, the capabilities of small underwater remotely operated vehicles (ROVs) have improved significantly and reduced in cost. They are now considered useful additions to invasive marine species surveillance programs.
In 2018, the Australian Government Department of Agriculture, Water and the Environment provided funding via the Agricultural Competitiveness White Paper to investigate if ROVs could be used to support surveillance and inspection activities. The overall aim was to evaluate available ROVs and examine how they might be incorporated into future invasive marine species surveillance programs. To achieve this, three specific objectives were identified:
- Following the recent development of a new generation of observation-class ROVs (OROVs), examine available units and assess their fitness-for-purpose.
- Determine if a cost-effective and easily transported OROV was available or could be developed for less than $35,000.
- Increase knowledge within government biosecurity departments on the potential use of OROVs in marine biosecurity response activities by development a training course for personnel.
The first step of the assessment stage was to undertake a desktop review of commercially available OROVs. Based on the recommendations of previous studies, this review process was restricted to battery powered OROVs with a vectored thruster design. Desirable characteristics were: six degrees of freedom, high quality image recording, easily transported and able to be deployed by a two-person team. OROVs examined ranged from less than $5,000 to more than $100,000. Assessment findings were then used to guide the enhancement phase.
OROV units purchased as part of the assessment process were examined to determine how they could be further adapted for surveillance tasks. Enhancement and adaptation themes were divided into three basic areas: 1) simplifying operation,2) improving spatial awareness, and 3) improving reliability. Throughout this phase, there was an overarching goal of developing a modular system based on interchangeable components. By allowing swapping of hardware components, OROVs can be configured to accommodate specific needs and allow upgrade individual components. These modifications provide greater functional capacity and better reliability whist keeping the overall price below the target figure of $35,000.
The project also included OROV training of biosecurity personnel involved in marine pest management and the project team worked with local vocational training organisations to develop a two-day training workshop. Workshop content included basic theory of ROV operation, practical sessions, and training in marine biofouling assessment procedures.
Due to travel restrictions caused by COVID-19, the second workshop was held as a webinar with practical sessions streamed live to participants. This provided the unexpected benefit of demonstrating capacity to view OROV footage remotely. This function offers potential for marine pest experts to guide surveys, providing savings in inspection cost and travel time.
Several small OROVs are now available at low cost that have impressive performance but are not easily modified and therefore may not suited to all surveillance tasks. The BR-H OROV developed as part of this project was found to be particularly suited to inspection of ship hulls due to its ability to operating in both free-flying and crawler modes. This unit can also be easily adapted for use in other invasive marine species roles.
We recommend a two-tier approach to OROV use for IMS surveillance and inspection, utilising lower priced OROVs for routine inspections, whilst also maintaining a smaller number of higher capacity OROVs for more complicated tasks or where detailed assessment is required. We also recommend a coordinated approach to OROV use by Australian jurisdictions, with the objective to establish an OROV network that provides advice on most appropriate units, future modifications, operator training and has access to local technical support.
Author: Ellard, K.
Prepared By: Invasive Species Branch of Biosecurity Tasmania, Tasmanian Department of Primary Industries Parks Water and Environment.
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