• Journal of Institute of Control, Robotics and Systems
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• v.17 no.10
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• pp.1006-1013
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• 2011

In this paper, we propose an optimal posture control law for an unmanned bicycle by deriving linear bicycle model from fully nonlinear differential equations. We calculate each equilibrium point of a bicycle under any given turning radius and angular speed of rear wheel. There is only one equilibrium point when a bicycle goes straight, while there are a lot of equilibrium points in case of turning. We present an optimal equilibrium point which makes the leaning input minimum when a bicycle is turning. As human riders give rolling torque by moving center of gravity of a body, many previous studies use a movable mass to move center of gravity like humans do. Instead we propose a propeller as a new leaning input which generates rolling torque. The propeller thrust input makes bicycle model simpler and removes input magnitude constraint unlike a movable mass. The proposed controller can hold optimal equilibrium points using both steering input and leaning input. The simulation results on linear control for circular motion are demonstrated to show the validity of the proposed approach.

• Transactions on Control, Automation and Systems Engineering
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• v.3 no.3
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• pp.176-180
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• 2001

In this papers, we derive a simple kinematic and dynamic formulation of an unmanned electric bicycle. We also check the controllability of the stabilization problem of bicycle. We propose a new control algorithm for the self stabilization of unmanned bicycle with bounded wheel speed and steering angle by using nonlinear control based on the sliding patch and stuck phenomena which was introduced by W. Ham. We also propose a sort of optimal control strategy for steering angle and driving wheel speed that make the length of bicycle\`s path be the shortest. From the computer simulation results, we prove the validity of the proposed control algorithm.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.4
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• pp.47-55
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• 2011

In this paper, the management system for a bicycle station using 900 MHz RFID technology has been developed. Based on the several reasons such as environmental pollution, high oil prices, and the government's eco-friendly policies, a bicycle usage is increasing nowadays. Accordingly, a need for bicycle parking spaces has already been emerging and increasing around a bicycle station. But most of the bicycle parking system are operated by manually, and it causes somewhat inefficient. Therefore, this paper suggests an unmanned bicycle station using RFID technology. The proposed system is supported by the mobile applications that are operated in the smart phones, and which gives the real-time access to the information of bicycle station. The proposed system yields owners of bicycle owners the convenience and efficiency of the station management in order to maximize the function of the bicycle stations.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.51.3-51
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• 2001

In this paper, research of unmanned electric bicycle based on autonomic traveling is discussed. We derived dynamic equation of bicycle and introduced control theory that bicycle´s tilt angle and velocity is stable in some region. We implemented system using DSP processor, accelerometer and DC motor. Then, we carried out an experiment based on studied Control theory.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2004.04a
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• pp.446-449
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• 2004

In the former researches〔2〕〔5〕 for the unmanned bicycle system, we do only focus on stabilizing it by using the lateral motion of mass which plays important role in driving a bicycle system. In this papers, we suggest an algorithm for deriving steering angle and speed for a given desired tracking path. As you may see in this paper, load mass balance system plays important role in stabilization and it is also discussed. We propose a control algorithm for the autonomous self stabilization of unmanned bicycle by using nonlinear compensation-like control based on the Lyapunov stability theory We then propose a tracking control strategy by moving the center of load mass left and right respectively. From the computer simulation results, we can show the effectiveness of the proposed control strategy.

• The Journal of Korea Robotics Society
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• v.1 no.1
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• pp.73-80
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• 2006

Bicycle is one of convenient transportation system. In this paper, we derive a more precise kinematics of bicycle system compared with other ones which were suggested by other researchers. In the derivation of kinematics we adopted a physical concept called virtual wheel. We also propose an algorithm for deriving inverse kinematics of a bicycle system. In this paper, the meaning of inverse kinematics is to find the time functions of steering angle and driving wheel speed for a given desired path trajectory. From the computer simulation, we show the validity of our proposed algorithm for inverse kinematics of bicycle system.

• Journal of Digital Convergence
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• v.13 no.4
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• pp.247-252
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• 2015

The earth has been suffering from global warming and experiencing unusual weather caused by increased fossil fuel usage in the industrialization period. In spite of the continuous effort to resolve the problem, the amount of fossil fuel usage is increasing constantly. Public bicycle system has been introduced as a solution to the fundamental problem of the existing public transportation systems. Also public bicycle system has another advantage that riding bicycle can keep the users in good health. In this paper, a new ICT convergence public bicycle system is presented which resolves the problems of existing public bicycle systems. The presented system has strong points in low installation fee and low maintenance expenses. The effectiveness of the presented system will be proven by analyzing case studies.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.9
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• pp.850-855
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• 2006

This is concerned with the development and design of automatic maneuvering system using Differential Global Positioning System(DGPS). To achievement of autonomous maneuvering controller for giant ship, first, we investigated automatic maneuvering controller using DGPS in motor car. The sensors are configured with DGPS and digital compass. We calculated velocity and steering angle of motor car based on sensor signal. To design the controller, we derived the bicycle model and developed critically damped controller. The critically damped controller can be tracing previously appointed position in the fastest time. We are used a laptop computer to realize and the control algorithm is programmed by visual basic software. The obtained experimental results from developed system show unmanned motor car is good tracing planed positions. Hence, the system is looking forward to use the autonomous maneuvering control fur giant ship.

• The Journal of the Convergence on Culture Technology
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• v.7 no.2
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• pp.377-388
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• 2021

With the growth of the global sharing economy market, various sharing services have recently appeared in South Korea. Seoul city unmanned public bicycle rental service, "Ttareuni" is one of the services representing the shared mobility industry in South Korea. Although many users use this service, the usability of the mobile application, which is the essential medium of utilizing the service, is not improving. In this regard, this study conducted usability testing and in-depth interviews for Ttareungi's main users in their 20s and 30s to improve the user experience of the mobile application of Ttareungi. As a result, the problems of Ttareungi mobile application were identified, and based on this, design considerations for shared mobility services having publicity like Ttareungi were proposed. This is expected to contribute to improving the user experience of shared mobility services.

• The Journal of Korea Robotics Society
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• v.18 no.1
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• pp.93-98
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• 2023

In this paper, the development of an autonomous electric vehicle for logistics with a robotic arm is introduced. The manual driving electric vehicle was converted into an electric vehicle platform capable of autonomous driving. For autonomous driving, an encoder is installed on the driving wheels, and an electronic power steering system is applied for automatic steering. The electric vehicle is equipped with a lidar sensor, a depth camera, and an ultrasonic sensor to recognize the surrounding environment, create a map, and recognize the vehicle location. The odometry was calculated using the bicycle motion model, and the map was created using the SLAM algorithm. To estimate the location of the platform based on the generated map, AMCL algorithm using Lidar was applied. A user interface was developed to create and modify a waypoint in order to move a predetermined place according to the logistics process. An A-star-based global path was generated to move to the destination, and a DWA-based local path was generated to trace the global path. The autonomous electric vehicle developed in this paper was tested and its utility was verified in a warehouse.