• Journal of Institute of Control, Robotics and Systems
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• v.18 no.12
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• pp.1106-1114
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• 2012

To achieve synchronized motion between a wearable robot and a human user, the redundancy must be resolved in the same manner by both systems. According to the seven DOF (Degrees of Freedom) human arm model composed of the shoulder, elbow, and wrist joints, positioning and orientating the wrist in space is a task requiring only six DOFs. Due to this redundancy, a given task can be completed by multiple arm configurations, and thus there exists no unique mathematical solution to the inverse kinematics. This paper presents analysis on the kinematic and dynamic aspect of the human arm movement and their effect on the redundancy resolution of the human arm based on a seven DOF manipulator model. The redundancy of the arm is expressed mathematically by defining the swivel angle. The final form of swivel angle can be represented as a linear combination of two different swivel angles achieved by optimizing different cost functions based on kinematic and dynamic criteria. The kinematic criterion is to maximize the projection of the longest principal axis of the manipulability ellipsoid for the human arm on the vector connecting the wrist and the virtual target on the head region. The dynamic criterion is to minimize the mechanical work done in the joint space for each two consecutive points along the task space trajectory. As a first step, the redundancy based on the kinematic criterion will be thoroughly studied based on the motion capture data analysis. Experimental results indicate that by using the proposed redundancy resolution criterion in the kinematic level, error between the predicted and the actual swivel angle acquired from the motor control system is less than five degrees.

• Journal of Ocean Engineering and Technology
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• v.26 no.6
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• pp.59-65
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• 2012

In this research, a novel mater arm was studied as a teaching device for an underwater revolute robot arm used as a slave arm. The master arm was designed to be a seven-degree-of-freedom (DOF) structure, with a structure similar to that of the slave arm, and to be desktop size to allow it to be worn on a human arm. The master arm with encoders on the joints was used as an input device for teaching a slave robot arm. In addition, small electric magnets were installed at the joints of the master arm to generate the haptic force. A control system was designed to sense excessive force and torque in the joints of the master arm and protect it by controlling the position and velocity of the slave arm through the encoder signal of the master arm.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.20-23
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• 1996

This paper deals with the flexible manipulator with rotational and translational degrees of freedom, which has an arm of time-varying length with the prismatic joint. The tracking control problem of the flexible manipulator is considered. First we design the controller of the 2-type robust servo system based on the finite horizon optimal control theory for the trajectory planned as a discontinuous velocity. Next, to reduce the tracking error, we use the method of the dynamic programming and of modifying the reference trajectory in time coordinate. The simulation results show that the dynamic modeling is adequate and that the asymptotic stabilization of the flexible manipulator is preserved in spite of nonlinear terms. The PTP control error has been reduced to zero completely, and the trajectory tracking errors are reduced sufficiently by the proposed control method.

• Journal of Power Electronics
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• v.6 no.1
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• pp.8-17
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• 2006

In this paper, we propose a fault-tolerant control system for the position control and vibration suppression of a flexible arm robot. The proposed control system has a strain gauge sensor signal observer based on a reaction force observer and detects a fault by monitoring an estimated error. In order to improve the estimation accuracy, the plant parameters included in the sensor signal observer are updated by using the strain gauge sensor signal in normal time through the adaptive law. After fault detection, the proposed control system exchanges the faulty sensor signal for the estimated one and switches to a fault mode controller so as to maintain the stability and the control performance. We confirmed the effectiveness of the proposed control system through several experiments.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.131.1-131
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• 2001

At the present time, multimedia chip, internet application, and network equipment is designed by using ARM core. Because it has a good debugging, software compiler and needed low power. We must process a data coding to send a multimedia data by real time. So need to connect software and hardware algorithm. In this research, We design interface for ARM9/AMBA based board using VHDL for these function implementation. The board is used the ARM company´s ARM940T for software function implementation and Xilinx company´s Virtex E2000 for hardware function algorithm. The various hardware algorithm (ME,ME,DCT) block for performance can be implemented on this system.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.3
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• pp.376-380
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• 2010

The capability of automotive suspension system depends on steering safety of knuckle and lower control arm. In this study, light weight is applied with lower arm by the material of aluminium alloy. Distributed stress, fatigue life and proper vibration are analyzed with multiple loads happened by automobile. The durability of lower arm can be verified by the result of structural analysis.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.817-821
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• 1991

Coordinated motion control of two arms of a dual-arm robot has been studied by many researchers, because of it's potential application in assembly as well as the handling of large and heavy objects beyond the capacity of single arm. This paper derives dynamic equation of a dual-arm robot, and describes some constrains to pick up a simply shaped object at prespecified position on it. This paper concludes with describing both PD and self-tunning control algorithm for the above task.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.248-253
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• 1992

In the development of a high speed and light weight manipulator, it is necessary to consider the structural elasticity of a robotic arm. The analysis of the infinite mode dynamic of robotic arm must be performed to obtain the finite mode modelling to achieve the feasible controller design of the robotic arm. The modelling procedure of the robotic arm is also illustrated. The controlled mode of the modelled dynamic can be derived by truncating the higher vibrational mode to result in the low order system for the sampling in the control signal is confined to the higher mode. And it is controlled by the pole assignment which can compensate the unmodelled dynamic effects. The unmodelled dynamic can result in the instability of the controlled system, which is known as spillover. The controller design of the low order system is simulated by the pole assignment and optimal control theory.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.5
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• pp.541-546
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• 2010

When a flexible arm is rotated by a motor about an joint axis, transverse vibration may occur. The motor torque should be controlled in such a way that the moter rotates by a specified angle, while simultaneously stabilizing vibration of the flexible arm so that it is arrested at the end of rotation. In this paper, the dynamic model of flexible robot arm is modeled by using Bernoulli-Euler beam theory and Lagrange equation. Nonlinear control with hysteresis deadzone using the sliding sector theory with continued input function in the sector is proposed.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.754-757
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• 2003

The implementation of home network systems In ubiquitous computing environments requires middleware that provides a method to control and operate home appliance devices. The Universal Plug and Play (UPnP), which is based on the IPv4 protocol and running on a PC, consists of UPnP devices that provide relevant services and control points that control the devices. However, It is inappropriate to Implement UPnP devices on a PC, since the implementation on a PC requires much space and electrical power. In this paper, a small embedded home network device equipped with UPnP middleware is implemented on an embedded GNU/Linux system running on an ARM9 platform, in order to deal with such problems.