• ETRI Journal
• /
• v.38 no.5
• /
• pp.1008-1018
• /
• 2016

This paper presents a control scheme for the leader-following formation of multiple robots. The control scheme combines the sliding mode control (SMC) method with the nonlinear disturbance observer (NDOB) technique. The formation dynamics suffer from uncertainties because the individual robots are uncertain. Concerning such formation uncertainties, the leader-following formation dynamics are modeled. Assuming that the formation uncertainties have an unknown boundary, an NDOB-based observer was designed to estimate the formation uncertainties. A sliding surface containing the observer outputs has been defined. Regarding the sliding surface, an SMC-based controller was investigated to form uncertain robots. A sufficient condition in the sense of the Lyapunov theory was proven such that the formation system is asymptotically stable. Herein, some comparison results between the sole SMC method and the second-order SMC method are presented to demonstrate the effectiveness and feasibility of the control scheme for multiple robots in the presence of uncertainties.

• Journal of Institute of Control, Robotics and Systems
• /
• v.16 no.2
• /
• pp.120-125
• /
• 2010

This paper proposes an intelligent PID/Fuzzy control system for two humanoid robots to transport objects stably. When a robot transports an object while walking, a whole body system of a robot may not be stable due to vibration or external factors from a different departure speed error and a body movement of walking robots. Therefore, it is necessary to measure the horizontal and vertical locations and speeds of object, then calibrate the difference of departure speed between robots with PID/Fuzzy control. The results of simulation with two robots indicated that a proposed controller makes robots to transport an object stably.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.34S no.3
• /
• pp.33-45
• /
• 1997

In this paper, we propsoe a new method of th ecommunication system for cooperative behaviors and works in collective autonomous mobile robots. A communication function among the collective robots is essential to intelligent cooperative works. In genral, global communication is effective for small number of robots. However when the number of robot goes on increasing, this becomes difficult to be realized because of limited communication capacity and increasing amount of information to handle. And also the problems such as communciation interfeence and improper message transmission occur. So we propose local communication system based on infrared sensor to realize the cooperative behavior among robots as the solution of above problem. It is possible to prevent overflow of information and exchange of complex information by fusion sign board model which transmits the information to unspecified robots and message passing model which communicate a specific robot. And we formularize optimal communication range by analysis of information propagation mechanism from the proposed comunication system. At last we verify the effectiveness of the proposed communication system from example of cooperative works.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.59 no.11
• /
• pp.2103-2107
• /
• 2010

This paper deals with the recognition of multiple mobile robots equipped with RFID tag. In the case that the number of robots recognized by each RFID reader is larger than that of allocated slots, the clashing recognition occurs. And, in the case that the total number of robots recognized by all RFID reader is larger than that of real robots, the repetitious recognition occurs. We employ the dynamic frame slot allocation by using the ALOHA algorithm to prevent the clashing recognition and estimate the number of robots by using the received signal strength indication to prevent the repetitious recognition. The numerical experiment shows the reliability and the efficiency of the proposed method.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.10
• /
• pp.1428-1433
• /
• 2014

In this paper, we propose the formation control algorithm using the leader-following robots in given space. The proposed method is as follows: First, we plan a path of the leader robot for the obstacle avoidance. After that, we propose the formation control algorithm of the following robots using the position and the orientation angle of the leader robot. Also, we propose method for adjusting the formation of the swarm robots when the following robots detect an obstacles. Finally, we show the effectiveness and feasibility of the proposed method though some simulations.

• The Journal of Korea Robotics Society
• /
• v.14 no.3
• /
• pp.196-202
• /
• 2019

Snake robots are slower than wheeled robots or legged robots, while they have an excellent terrainability in a disastrous area. Considering their advantages and disadvantages, a legged robot whose legs are snake robots, 'Quadnake' was proposed in this research. Five motions of the snake were analyzed. Applying these motions, Quadnake could implement eight kinds of motions which snake robots and quadruped walking robots can implement. As a result of it, Quadnake can have the advantages of both a snake robot and a walking robot. It is expected to move stably in a harsh terrain with snake's motion and move fast with walking.

• The Journal of Korea Robotics Society
• /
• v.17 no.2
• /
• pp.152-158
• /
• 2022

As various mobile robots and manipulator robots have been commercialized, robots that can be used by individuals in their daily life have begun to appear. With the development of robots that support daily life, the interaction between robots and humans is becoming more important. Manipulator robots that support daily life must perform tasks such as pressing buttons or picking up objects safely. In many cases, this requires expensive multi-axis force/torque sensors to measure the interaction. In this study, we introduce a low-cost two-axis pressure sensor that can be applied to manipulators for education or research. The proposed system used three force sensitive resistor (FSR) sensors and the structure was fabricated by 3D printing. An experimental device using a load cell was constructed to measure the biaxial pressure. The manufactured prototype was able to distinguish the +-x-axis and the +-y-axis pressures.

• The Journal of Korea Robotics Society
• /
• v.17 no.1
• /
• pp.86-92
• /
• 2022

Utilization of small robots in psychology and biology provides a new breakthrough in understanding the neurobiological mechanisms of various animal behavior. The expansion of robot use in animal research is partly due to increased availability of economically plausible mobile robots and also due to the current shift in animal research toward more ecologically valid experiments. Ground-breaking experimental findings are expected when the behavioral variables are manipulated in more natural situations. In addition, the results from laboratory could be generalized more easily with added ecological validity. The current paper attempts to review a wide range of applications of animal robots used to study animal behavior and to highlight major advantages and limitations. In particular, this review focuses more on the psychological impact of animal robots than engineering details about their structure and operation. Finally, this review will provide some practical considerations when employing robots in animal experiments.

• International Journal of Advanced Culture Technology
• /
• v.11 no.1
• /
• pp.165-170
• /
• 2023

This study focuses on the development of intelligent combat robot systems for future warfare. The research is structured as follows: First, the introduction presents the rationale for researching intelligent combat robots and their potential to become game changers in future warfare. Second, in the context of the intelligent robot paradigm, this study proposes the need for military organizations to innovate their combat concepts and weapon systems through the effective utilization of Artificial Intelligence, Cognitive, Biometric, and Mechanical technologies. This forms the theoretical background of the study. Third, the analysis of intelligent robot systems considers five examples: humanoid robots, jumping robots, wheeled and quadrupedal pack robots, and tank robots. Finally, the discussion and conclusion propose that intelligent combat robots should be selected as game changers in military organizations for future warfare, and suggest further research in this area.

• The Journal of the Korea Contents Association
• /
• v.18 no.3
• /
• pp.592-600
• /
• 2018

As the field of robots is evolving to intelligent robots that can replace even humans' mental or emotional labor, 'robot ethics' needed in relationship between humans and robots is becoming a crucial issue these days. The purpose of this study is to consider the ethics of robots and humans that is essential in this post-human age. It will deal with the followings as the main contents. First, with the cases of developing ethics software intended to make robots practice ethics, the authors begin this research being conscious about the matter of whether robots can really judge what is right or wrong only with the ethics codes entered forcibly. Second, regarding robot ethics, we should consider unethicality that might arise from learning data internalizing human biasness and also reflect ethical differences between countries or between cultures, that is, ethical relativism. Third, robot ethics should not be just about ethics codes intended for robots but reflect the new concept of 'human ethics' that allows humans and robots to coevolve.