Biomimetic Swimming Mini-Robots Using Electro-Magnetic Actuation (EMA) System

Hyunchul Choi,Semi Jeong,Cheong Lee,Youngho Ko,Seong Young Ko,Jong-Oh Park,Sukho Park 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

For the actuation of mini-robots, electromagnetic based actuation (EMA) methods were proposed. EMA system has many advantages for the wireless actuation of mini-robots. This paper introduces our proposed biomimetic swimming mini-robots such as tadpole robot and jellyfish robot. The biomimetic swimming mini-robots could be driven by an external alternating magnet field using three pairs of Helmholtz coils. The swimming mini-robots consist of a buoyant robot body, permanent magnets, and fins. Especially, the tadpole mini-robot has a single fin which is directly linked to the permanent magnet and the jellyfish mini-robot has multiple fins which have a permanent magnet at the end of fin. The external alternating magnetic field from three pairs of Helmholtz coils could generate the propulsion and steering force of the tadpole mini-robot and the jellyfish mini-robot in 2- and 3-dimensional (-D) space. Firstly, we demonstrated the fabrications of the EMA coil system and the mini-robots. Secondly, we summarized the locomotive algorithms of the mini-robots using EMA. Thirdly, we setup the control system for the EMA driven mini-robots, which consists of EMA coils, dual cameras, controller, power amplifier, and conventional joystick. Through various experiments, we evaluated the locomotion algorithms the swimming mini-robots using EMA system. Finally, we demonstrated the performances of the swimming mini-robots in 2-D and 3-D space.

Wireless Biomimetic Swimming Mini-Robots Using Electro-Magnetic Actuation (EMA) System

Hyunchul Choi,Semi Jeong,Cheong Lee,Gwangjun Go,Kiduk Kwon,Seong Young Ko,Jong-Oh Park,Sukho Park 제어로봇시스템학회 2013 제어로봇시스템학회 국제학술대회 논문집 Vol.2013 No.10

For the actuation of mini-robots, various types of electromagnetic based actuation (EMA) methods were proposed. Compared with conventional actuation system using electric motor, EMA system has many advantages for the wireless actuation of mini-robots. This paper introduces our proposed biomimetic swimming mini-robots such as tadpole robot and jellyfish robot. The developed biomimetic swimming mini-robots could be driven by an external alternating magnet field using three pairs of Helmholtz coils. The swimming mini-robots consist of a buoyant swimming mini-robot body, permanent magnets, and fins. Especially, the tadpole swimming mini-robot has a single fin which is directly linked to the permanent magnet and the jellyfish swimming mini-robot has multiple fins which have a permanent magnet at the end of fins. The external alternating magnetic field from three pairs of Helmholtz coils could generate the propulsion and steering force of the tadpole mini-robot and the jellyfish mini-robot in 2- and 3-dimensional (D) space.

다관절 유영로봇에 적용하기 위한 물방개의 유영패턴 분석

김희중,이지홍 한국로봇학회 2012 로봇학회 논문지 Vol.7 No.4

In these days, researches about underwater robots have been actively in progress for the purposes of ocean detection and resource exploration. Unlike general underwater robots such as ROV(Remotely Operated Vehicle) and AUV(Autonomous Underwater Vehicle) which have propellers, an articulated underwater robot which is called Crabster has been being developed in KORDI(Korea Ocean Research & Development Institute) with many cooperation organizations since 2010. The robot is expected to be able to walk and swim under the sea with its legs. Among many researching fields of this project, we are focusing on a swimming section. In order to find effective swimming locomotion for the robot, we approached this subject in terms of Biomimetics. As a model of optimized swimming organism in nature, diving beetles were chosen. In the paper, swimming motions of diving beetles were analyzed in viewpoint of robotics for applying them into the swimming motion of the robot. After modeling the kinematics of diving beetle through robotics engineering technique, we obtained swimming patterns of the one of living diving beetles, and then compared them with calculated optimal swimming patterns of a robot leg. As the first trial to compare the locomotion data of legs of the diving beetle with a robot leg, we have sorted two representative swimming patterns such as forwarding and turning. Experimental environment has been set up to get the motion data of diving beetles. The experimental equipment consists of a transparent aquarium and a high speed camera. Various swimming motions of diving beetles were recorded with the camera. After classifying swimming patterns of the diving beetle, we can get angular data of each joint on hind legs by image processing software, Image J. The data were applied to an optimized algorithm for swimming of a robot leg which was designed by robotics engineering technique. Through this procedure, simulated results which show trajectories of a robot leg were compared with trajectories of a leg of a diving beetle in desired directions. As a result, we confirmed considerable similarity in the result of trajectory and joint angles comparison.

Design and performance analysis of a novel swimming robot with waterbomb origami wheel

Junfeng Hu,Ning Zhang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.9

This paper proposes a novel swimming robot with waterbomb origami wheel. The wheel of the swimming robot is a waterbomb origami that acts like a paddle blade. The origami wheel provides a new propulsion way for the swimming vehicle. The propulsion principle is to use the water flow to push the origami structure like the blade to propel it move forward. The analytical model describing the mechanical behavior of the origami wheel was built to illustrate the superior swimming characteristics of the robot. The model uncovers propulsive force variation with respect to origami structure parameters. The prototypes of the swimming robot are manufactured to analyze the influence of the structural parameters on their performances such as swimming speed, steering, and propulsive force. The analysis results showed that the proposed swimming robot has advantages such as high propulsion force and fast response. Meanwhile, it provides a guideline for the structural design of the origami wheel that enables it to be suitable to swim in the water. In a word, the origami wheel provides a light and efficient propulsion for swimming vehicles. The origami wheel provides a novel and simple propulsion way for swimming vehicles, and the structure promotes the development of a new class of swimming vehicles.

유영과 보행이 가능한 생체모방 수중 로봇의 설계개념과 근사모델을 활용한 모의실험

김희중,전봉환,이지홍 한국로봇학회 2014 로봇학회 논문지 Vol.9 No.1

This paper describes the design concept of a bio-inspired legged underwater and estimating its performance by implementing simulations. Especially the leg structure of an underwater organism, diving beetles, is fully adopted to our designing to employ its efficiency for swimming. To make it possible for the robot to both walk and swim, the transformable kinematic model according to applications of the leg is proposed. To aid in the robot development and estimate swimming performance of the robot in advance, an underwater simulator has been constructed and an approximated model based on the developing robot was set up in the simulation. Furthermore, previous work that we have done, the swimming locomotion produced by a swimming patten generator based on the control parameters, is briefly mentioned in the paper and adopted to the simulation for extensive studies such as path planning and control techniques. Through the results, we established the strategy of leg joints which make the robot swim in the three dimensional space to reach effective controls.

수중유영로봇 Crabster의 최적 유영 구현

김대현,이지홍 한국로봇학회 2012 로봇학회 논문지 Vol.7 No.4

Recently, development of underwater robot has actively been in progress in the world as ROV(Remotely Operator Vehicle) and AUV(Autonomous Unmmanded Vehicle) style. But KIOST(Korea Institute of Ocean Science and Technology), beginning in 2010, launched the R&D project to develop the robot, dubbed CRABSTER(Crab + (Lob)ster) in a bid to enhance the safety and efficiency of resource exploration. CRABSTER has been designed to be able to walk and swim with its own legs without screws. Among many research subjects regarding CRABSTER, optimal swimming patterns are handled in this paper. In previous studies, drag forces during one period with different values for angle of each joint were derived. However kinematics of real-robot and fluid-dynamics are not considered. We conducted simulations with an optimization algorithm for swimming by considering simplified fluid dynamics in this paper. Drag-coefficients applied to the simulation were approximated values calculated by CFD(Computational Fluid Dynamics : Tecplot 360, ANSYS). In addition, optimized swimming patterns were applied to a real robot. The experiments with the real robot were conducted in circumstances in the water. As a result, when the experiments were carried out in the water, a regular pattern of drag force output came out depending on the movement of the robot. We confirmed the fact that the drag forces from the simulation and the experiment has a high similarity.

수중보행 로봇의 벡터 추진방식을 이용한 유영 알고리즘 설계

최현정,유승열 대한기계학회 2023 大韓機械學會論文集A Vol.47 No.8

This paper describes swimming algorithm design using vector thrusting method for an underwater legged robot that can deal safely and quickly with ocean accidents caused by marine waste such as discarded fishing nets and ropes. To develop the algorithm, we derived the mathematical model of vector thrusting technique of ROVs (remotely operated vehicles) and applied it to a twelve degree of freedom (DOF) kinematic model of underwater walking quadruped robot. We then calculated the final force on the robot’s body from the leg-posture with attached propellers on the leg-links. Furthermore, we solved insufficient DOF problem of the four DOF leg to calculate thrusting force orientations by introducing virtual joints concept. Through this process, we finally derived a swimming algorithm based on vector thrusting method according to the leg posture and validated the algorithm through simulation. 본 논문에서는 최근 증가하고 있는 폐어망, 폐로프 등 해양 폐기물에 의한 부유물 감김 사고의 수습을 안전하고 신속하게 하기 위하여, 선저 어망 제거를 위한 수중보행 로봇의 다리 부착형 추진기를 이용한 벡터 추진기법 기반의 유영 알고리즘에 대하여 기술하고자 한다. 이를 위해, ROV 추진 시스템을 기준으로 벡터 추진기법의 수학적 모델을 유도하고, 이를 보행 로봇 형태의 12 자유도 기구학 모델로 확장하고, 보행 로봇의 다리 자세에 따른 추력 산출 모델을 유도하였다. 또한, 추력의 방향각을 구하는 과정에서 4 자유도 다리의 부족 자유도 문제를 해결하기 위하여 가상 관절을 도입하여 4족 보행 로봇의 다리 자세에 따른 추력 합산 모델을 유도하였다. 이를 통해, 수중 로봇의 유영 이동 시, 다리 자세에 따른 최종 추력을 계산하였다.

Realization of Fish Robot Position Recognition Object Using the Color Segment

Lenendra Chowdary Gunnam,Kyoo Jae Shin 한국정보기술학회 2016 Proceedings of KIIT Conference Vol.2016 No.6

In this paper, we have researched about how to detecting the fish robot objects in aquarium. We had used designed fish robots DOMI ver1.0, which had researched and developed for aquarium underwater robot. The model of the robot fish is analysis to maximize the momentum of the robot fish and the body of the robot is designed through the analysis of the biological fish swimming. We are planned to non-external equipment to find the position and manipulated the position using creating boundary to fish robot to detect the fish robot objects. Also, we focused the detecting fish robot in aquarium by using boundary algorithm. In order to the find the object boundary, it is filtering the video frame to picture frames and changing the RGB to gray. Then, applied the boundary algorithm stand of equations which operates the boundary for objects. We called these procedures is kind of image processing that can distinguish the objects and background in the captured video frames. It was confirmed that excellent performance in the field test such as filtering image, object detecting and boundary algorithm.

수중보행로봇의 벡터추진방식을 이용한 유영알고리즘 설계

최현정(H.J. Choi),유승열(S. Y. Yoo) 대한기계학회 2022 대한기계학회 춘추학술대회 Vol.2022 No.11

This paper describes the development of swimming algorithm using vectored thrustors mounted on the legs of underwater walking robot. The robot is developing for removing fishnet in the ship propellers and the robot approaches to the bottom of the ship by swimming. In this paper, we developed calculation algorithm using thrusting vectors on the feet and conformed the algorithm with kinematic simulation.

물고기형 수중로봇의 유영메커니즘 및 알고리즘 개발 1

류영선 한국로봇학회 2009 로봇학회 논문지 Vol.4 No.1

Generally, underwater vehicle type of propeller shows low efficiency about 50% - 55%. However, the efficiency of swimming mechanism of a fish is 60% -70%, more efficient about 20% than screw propellers. Recently, research of underwater vehicle type of fish increase due to its good efficiency and is regarded as a typical bio-mimical robot. In this research, a new algorithm and mechanism that show low energy consumption imitating swimming mechanism of fish proposed increasing speed and running time in field trial.