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Modelling and control of a 6 DOF robot manipulator for underwater applications - aquaculture related case studies


This paper presents kinematic models and a dynamic
model of a 6 degree of freedom (DOF) underwater robot
manipulator for aquaculture applications. Robotics has emerged
as a key enabling technology in the industrialisation of salmon
aquaculture. Although this is most apparent in the sea-based
production phase, there is an increasing interest in using robotic
tools in the land-based phase of the production cycle where fish
are reared from eggs to smolts ready for sea transfer. The model
presented here is a key component in achieving this goal, as
it enables simulations of robotic operations in land-based fish
facilities, and also can serve as a potential component in new
control system components and solutions.
The model was developed based on a commercially available
robotic manipulator arm designed for underwater usage deemed
suitable for in-tank operations called Reach Bravo 7 (Blueprint
Lab). Forward kinematics were derived using the Denavit-
Hartenberg parameters, while inverse kinematics were found
numerically using the Levenberg-Marquardt method. A dynamic
model for the submerged manipulator combining conventional
robotic manipulator theory with advanced hydrodynamics was
also developed. Together these elements comprise a software
suite that can function as a virtual laboratory for testing new
solutions in planning, guidance, navigation and control required
to use robotic manipulators for underwater operations such as
tank cleaning and dead fish removal. The outcomes of this work
will thus be a first step towards fully autonomous operations in
commercial land-based fish holding facilities.


Academic lecture


  • Research Council of Norway (RCN) / 296476




  • SINTEF Ocean / Aquaculture
  • Norwegian University of Science and Technology

Presented at

Oceans 2021


San Diego – Porto


20.09.2021 - 23.09.2021



View this publication at Cristin