• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.454-457
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• 2002

This paper presents a new motion control for singularity avoidance in 6 DOF articulated robot manipulators, based on a speed limiting algorithm for joint positions and velocities. For a given task, the robot is controlled so that the joints move with acceptable velocities and positions within the reachable range of each joint by considering the velocity limit. The proposed method was verified using MATLAB-based simulations.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1539-1543
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• 2004

This paper describes platform overview, system integration and dynamic walking control of the humanoid robot, KHR-2 (KAIST Humanoid Robot - 2). We have developed KHR-2 since 2003. KHR-2 has totally 41 DOF (Degree Of Freedom). Each arm including a hand has 11 DOF and each leg has 6 DOF. Head and trunk also has 6 DOF and 1 DOF respectively. In head, two CCD cameras are used for eye. In order to control all joints, distributed control architecture is adopted to reduce the computation burden of the main controller and to expand the devices easily. The main controller attached its back communicates with sub-controllers in real-time by using CAN (Controller Area Network) protocol. We used Windows XP as its OS (Operating System) for fast development of main control program and easy extension of peripheral devices. And RTX, HAL(Hardware Abstraction Layer) extension program, is used to realize the real-time control in Windows XP environment. We present about real-time control of KHR-2 in Windows XP with RTX and basic walking control algorithm. Details of the KHR-2 are described in this paper.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.579-584
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• 2004

In this paper, we present the mechanical, electrical system design and system integration of controllers including sensory devices of the humanoid, KHR-2 (KAIST Humanoid Robot - 2). We have developed KHR-2 since 2003. Total number of DOF of KHR-2 is 41. Each arm including a hand has 11 DOF and each leg has 6 DOF. Head and trunk also has 6 DOF and 1 DOF respectively. In head, two CCD cameras are used for eye. To control all axes efficiently, distributed control architecture is used to reduce computation burden of main controller and to expand devices easily. So we developed the sub-controller as a servo motor controller and a sensor interfacing devices using microprocessor. The main controller attached its back communicates with sub-controllers in real-time by CAN (Controller Area Network) protocol. We used Windows XP as its OS (Operation System) for fast development of main control program and easy extension of peripheral devices. And RTX HAL extension commercial software is used to realize the real-time control in Windows XP environment.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.6
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• pp.543-551
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• 2015

In this study, a novel method for dimension measurement of large-scale moving objects using stereo camera with 2-degree of freedom (2-DOF) mechanism is presented. The proposed method utilizes both the advantages of stereo vision technique and the enlarged visibility range of camera due to 2-DOF rotary mechanism in measuring large-scale moving objects. The measurement system employs a stereo camera combined with a 2-DOF rotary mechanism that allows capturing separate corners of the measured object. The measuring algorithm consists of two main stages. First, three-dimensional (3-D) positions of the corners of the measured object are determined based on stereo vision algorithms. Then, using the rotary angles of the 2-DOF mechanism the dimensions of the measured object are calculated via coordinate transformation. The proposed system can measure the dimensions of moving objects with relatively slow and steady speed. We showed that the proposed system guarantees high measuring accuracy with some experiments.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2020.11a
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• pp.260-262
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• 2020

본 논문은 6DOF 위치기반 자기장 센서(Liverty Latus, Pollhemus)를 사용한 가상현실 방송제작에서 사용할 수 있는 인터랙티브 증강현실 시스템, K-Pointer를 제안한다. 우리는 방송에서 추적 및 인식의 정확성을 높이기 위해 Pollemus사의 6DOF 자기장기반 위치 추적 센서 리버티(수신부,소스)와 라투스(송신부,마커), 그리고 4입력 버튼장치를 결합한 인터페이스를 가지고 기존 방송용 증강현실 시스템과 통합하여 새로운 인터랙티브 증강현실 시스템을 개발하였다. 본 시스템은 방송용 증강현실 그래픽 합성 시스템(수신부)과 센서의 위치정보와 버튼 이벤트를 전송하는 시스템(송신부)으로 구성되며, 센서추적정보와 버튼이벤트 정보는 UDP로 실시간으로 수신부로 전송된다. 우리는 사용자 손의 모션과 버튼이벤트로 그래픽 정보를 인터랙티브하게 제어할 수 있게 하였다. 결과적으로 본 시스템은 기존의 합성중심의 방송용 증강현실 시스템을 사용자의 모션 기반 그래픽을 제어할 수 있는 인터랙티브 증강현실시스템으로 그 기능을 확장 시킬 수 있게 한다. 제안된 시스템은 광학식 추적을 하지 않기 때문에 조명의 변화에 영향이 없으며, 라투스 수신기가 작기 때문에 손에 쥐었을 때 거의 보이지 않고 가려도 추적이 강인하여 버튼장치를 통해 사용자가 정확한 이벤트로 직접 그래픽을 그리거나 쉽게 제어할 수 있는 장점이 있다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.5
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• pp.381-389
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• 2007

6-DOF simulation program is developed in order to increase the efficiency of the store separation analysis. This S/W is much faster than a method based on CFD(Computational Fluid Dynamics) technology, and allows the simulation of stores with fixed shape as well as with extensible wings, because it uses aerodynamic databases which are prepared beforehand. In this paper, aerodynamic databases of stores are obtained with MSAP(Multi-body Separation Analysis Program), and unsteady damping coefficients are modeled with Missile Datcom. These databases and the 6-DOF simulation program are used to predict the trajectory of an external store, while its wings are being deployed. The analysis results indicate that the safe separations of the store can be achieved not only with the wing fixed but with the wings being deployed.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1513-1518
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• 1996

A force reflecting hand controller can be used to provide more realistic information to the operator of a teleoperation system such as kinesthetic feedback from a slave robot. In this paper, a new design concept of a force reflecting 6-DOF hand controller utilizing the kinematic structure of a Stewart Platform is presented. Based on the optimal design technique of a Stewart Platform, a force reflecting hand controller has been designed and constructed to verify the technical feasibility of proposed design concept. In order to provide an operator with kinesthetic feedback information, a force mapping algorithm based on a reciprocal product of screws has been introduced. Finally, the technical feasibility of the design concept has been demonstrated through some of experimental results of the device under virtual environment on a real-time graphic system.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.1
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• pp.1-7
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• 2012

In this paper Vehicle driving simulator have been used in the development and modification of models. A real-time simulation system and washout algorithm for an excavator have been developed for a driving simulator with six degrees of freedom. An interesting question, "how the 6 DOF Driving Simulator can be controlled optimally for the various tasks?" is not easy to be answered. This paper presents the hardware and software developed for a driving simulator of construction vehicle. A simulator can reduce cost and time a variety of driving simulations in the laboratory. Using its 6 DOF Simulator can move in various modes, and perform dexterous tasks. Driving simulators have begun to proliferate in the automotive industry and the associated research community. This effort involves the real-time dynamic of wheel-type excavator the design and manufacturing of the Stewart platform an integrated control system of the platform and three-dimensional graphic modeling of the driving environments.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.1
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• pp.63-72
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• 2003

A new 6-DOF parallel haptic device is proposed. Many existing haptic devices require large power due to having floating actuator and also have small workspaces. The proposed new mechanism can generate 6-DOF reflecting force. This device is relatively light by employing non-floating actuators and has large workspace. Kinematic analysis and kinematic optimal design is performed for this mechanism. Dexterous workspace, global isotropic index, and global maximum force transmission ratio are considered as kinematic design indices. To deal with such multi-criteria optimization problem. composite design index is employed. For the given operational specifications, actuator sizing for this mechanism is also carried out.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.37.6-37
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• 2002

Omnidirectional mobile robots are capable of arbitrary motion in an arbitrary direction without changing the direction of wheels, because they can perform 3 degree-of-freedom (DOF) motion on a 2-dimensional plane. In this research, a new class of an omnidirectional mobile robot is proposed. Since it has synchronously steerable omnidirectional wheels, it is called an omnidirectional mobile robot with steerable omnidirectional wheels (OMR-SOW). It has 3 DOFs in motion and one DOF in steering. One steering DOF can function as a continuously variable transmission (CVT). CVT of the OMR-SOW increases the range of velocity ratio from the wheel velocities to robot velocity, which may improve...