Μάνος Νικόλαος

Περίληψη:
Underwater vehicles can play an essential role in fish farming and their construction can be a challenging aspect of their development owing to the necessity of waterproofing electronic components. This paper describes the construction and basic framework of a robotic vehicle named "Kalypso," which was developed to inspect nets in fish farms. Kalypso can distinguish between clean areas on the net and areas that are either torn or covered in algae, based on an algorithm. Also, it is equipped with sensors to estimate position, depth, temperature and leakage, which can detect water in the watertight housing. The watertight part of the robot includes cable plugs, some of which are detachable to facilitate the connection of various devices, such as sensors and lights. Kalypso has two cameras, one facing the front and another facing the bottom. Furthermore, the robot has underwater ultrasonic sensors, which measure the distance from the environment, and LED lights on the front for increased visibility in low-light environments. Several tests were carried out, both inside fish farm nets and in the open sea.

Περίληψη:
A significant challenge in fish farms is net cage deterioration, which leads to fish escapes owing to holes and can have a severe influence on the fish's health due to biofouling. To reduce fish losses, divers are utilized on a weekly basis by fisheries to carry out the task of inspecting the net cages. Companies that are involved in aquaculture are always seeking for methods to increase their profits, and one of those ways is to cut down on the costs of maintenance. This paper is about the development of an unmanned underwater vehicle used for inspection in net cages at Kefalonia Fisheries in Greece. This vehicle has a 3D-printed body and a six-thruster configuration, featuring five degrees of freedom. The vehicle's primary goal is to reduce divers’ expenses by conducting inspections more frequently. In this work, the design, manufacture, and control are presented along with the experimental results and flow simulation of the vehicle. The suggested design is versatile and robust while yet being affordable, and the fisheries may easily adopt it due to its inexpensive price and simplicity of operation.

Περίληψη:
Educational robotics is rooted in Constructionism and allows learners to investigate and discover new concepts. It would appear that learning a programming language while programming a robot is more motivating and productive than conventional methods. El Greco platform is an educational platform built to teach Python. Users can control El Greco from any computer connected to the Internet due to the platform’s web-based interface. El Greco is a social humanoid robot built to be affordable and appropriate for use in education. Potential users can use Python direct code entry or the Blockly library to control El Greco. The Blockly library embeds an editor in an application to represent coding notions like interlocking blocks. Unique functions that control El Greco were created. The inserted code can be executed on the website or by the Robot. The user can view the result of code execution through a live-streaming window. The El Greco platform has been designed with students in mind but is available to anyone at no cost.

Περίληψη:
Remotely Operated Underwater Vehicles (ROVs) used in net cages at fish farms are usually employed to inspect net wear and biofouling. Implementing a robotic system to repair the damages can reduce diver costs and can be lucrative for the aquaculture company. This paper presents the design, fabrication, and modeling of an affordable subsea robotic arm called IURA, that can be integrated to any underwater vehicle. For this study Kalypso ROV was used. Although IURA is at its infancy, it features (i) high modularity allowing to change end-effector tool effortlessly, and (ii) lowcost which makes it feasible for any ROV integration. It is mostly 3D-printed and has two servo motors as joints featuring 2 Degrees of Freedom (DoF). Two manipulators were tested, one to dispose fish morts, and another to remove objects from the net cages at fish farms. In this work, the design of IURA will be presented along with the fabrication and sealing of the arm. Furthermore, the modeling of the robotic arm will be quoted and flow simulation of both end-effectors. Finally, the experimental results will be discussed. The proposed design features customizability and sturdiness while retaining low-cost and can be used for subsea operations at Kefalonia Fisheries’ net cages when mounted on Kalypso ROV.

Περίληψη:
This paper introduces the conception, design, fabrication, and control of a modular remotely operated underwater vehicle. It is an affordable submarine robot intended for inspection operations in shallow depths. It has a 3D-Printed hull, and it can be adjusted according to the respective needs. It is equipped with six thrusters which allow it to have five Degrees of Freedom enabling increased maneuverability while it operates. The robot has marginally positive buoyancy which allows it to emerge in case of a malfunction, and the fins attached to the motors enhance its stability. The design, development, and construction as well as the components and electronics of the vehicle are presented. Moreover, the forces acting on the ROV and the buoyancy are introduced, along with the motion generation of the motors. The IMU sensor calibration is explained and a dataset of the rotational movement was analyzed into 3 axes. The proposed design features low cost, customizability and sturdiness allowing the user to configure and operate by himself.

Περίληψη:
This paper deals with a system consisting of a robot named El Greco that can be programmed via internet and livestreaming from any place, anywhere, to move on a play room as well as perform other functions such as to produce voice in many languages, recognize voice commands, recognize faces, perceive its environment, perform combined movements and provide information by searching the Internet. All these capabilities of the robot can be programmed using a friendly block programming platform that has been developed to be used by students for educational purposes. The system was used by a number of students and the results of two questionnaires before and after the use are reported.