• Journal of Sensor Science and Technology
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• v.24 no.2
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• pp.137-143
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• 2015

This paper describes the design of a two-axis force sensor with two step plate beams for measuring forces in an upper-limb rehabilitation robot. The two-axis force sensor is composed of a Fz force sensor and a Ty torque sensor. The Fz force sensor measures the force applied to a patient's arm pushed by a rehabilitation robot and the force of patient's arm. The Ty torque sensor measures the torque generated by a patient's arm motion in an emergency. The structure of sensor is composed of a force transmitting block, two step plate beams and two fixture blocks. The two-axis force sensor was designed using FEM (Finite Element Method), and manufactured using strain-gages. The characteristics test of the two-axis force sensor was carried out. as a test results, the interference error of the two-axis force sensor was less than 1.24%, the repeatability error of each sensor was less than 0.03%, and the non-linearity was less than 0.02%.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.247-252
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• 2004

Developed shape awareness technology and vision technology for optical ten slant in this research and including external form state of lens for the performance verification developed so that can be good achieve badness finding. And, establish to existing reflex data because inputting surface badness degree of scratch's standard specification condition directly, and error designed to distinguish from product more than schedule error to badness product by normalcy product within schedule extent after calculate the error comparing actuality measurement reflex data md standard reflex data mutually. Developed system to smallest 1pixel unit though measuring is possible 1pixel as 3.7$\mu\textrm{m}$${\times}$3.7$\mu\textrm{m}$(0.1369${\times}$10/sub-1/$\textrm{mm}^2$) the accuracy to 10/sub-1/mm minutely measuring is possible performance verification and trust ability through an experiment prove.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.929-934
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• 2004

As 3D scanner develops, it can be used in measurement. To accomplish complete 3D measurement, the scanner has to view different sides of the target. It can be done by moving the scanner and fix it at every measuring point. By human, it would take so much time. However, by using robot, measuring time can be reduced and the procedure can be automated. It is suitable for 6R serial manipulator to do this kind of work in which the scanner should go any position in arbitrary orientation. We did inverse kinematics analysis by analytical and graphical methods. Then, we compared two methods.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.836-839
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• 2004

Qualitative elevation of products is very important Part. A business racking us brains to find for qualitative elevation of products. Recently, measurement accuracy of a non-contact 3D scanner has been rapidly improving. As a result, the number application cases of non-contact 3D scanners are increasing. A non-contact 3D scanner is capable of measuring a curved surface rapidly and has high resolution. It is more affordable and potable than the CMMs, It is therefore expected to be applied more frequently in more diverse industries. Automating the measuring process using a non-contact 3D scanner and developing a technology, which allows a user to measure easily, will eventually improve the quality of products. As their inspection and analysis processes improve.

• Journal of Radiation Industry
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• v.7 no.2_3
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• pp.121-126
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• 2013

The new algorithm technique is necessary to incorporate for analyzing and evaluating extreme condition like a nuclear accident. In this study, the combined methodology for measuring the three-dimensional space was compared with SIFT (Scale Invariant Feature Transform) and SURF (Speeded-Up Robust Feature) algorithm. The suggested method can be used for the acquisition of spatial information using the robot vision in the districted area of the nuclear facilities. As a result, these data would be helpful for identify the damaged part, degree of damage and determination of recovery sequences.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1418-1423
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• 2003

In this paper, a nonlinear controller based on sliding mode control is applied to a two -wheeled Welding Mobile Robot (WMR) to track a smooth-curved welding path at a constant velocity of the welding point. T he mobile robot is considered in terms of dynamics model in Cartesian coordinates and its parameters are exactly known . To obtain the controller, the tracking errors are defined, and the two sliding surfaces are chosen to guarantee that the errors converge to zero asymptotically. Two cases are to be considered: fixed torch and controllable torch. In addition, a simple way of measuring the errors is introduced using two potentiometers. The simulation results are included to illustrate the performance of the control law.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.9
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• pp.863-868
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• 2015

In this paper, the vibration of a single-wheel mobile robot is minimized by designing a filter. An AHRS (Attitude and heading reference system) sensor is used for measuring the state of the robot. The measured signals are analyzed using the FFT method to investigate the fundamental vibrational frequency with respect to the flywheel's speed of the gimbal system. The IIR notch filter is then designed to suppress the vibration at the identified frequency. After simulating the performance of the designated filter using the measured sensor data through extensive experiments, the filter is actually implemented in a single-wheel mobile robot, GYROBO. Finally, the performance of the designed filter is confirmed by performing the balancing control task of the GYROBO system.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.3
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• pp.243-251
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• 2014

In inference fit assembly process of the industrial robot, it basically needs the force data. One of the typical methods to get the force data is attaching torque sensors on the robot arm joint or end effector. This is effective way to reduce time delay and to improve preciseness of force control, but this method has several problems. To solve that problem, this paper suggests method which measures assembly force without torque sensor by using the sliding perturbation observer(SPO) and assembly process based on SPO to assemble successfully in inference assembly

• Journal of the Korean Society for Precision Engineering
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• v.14 no.5
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• pp.134-142
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• 1997

In this study, we proposed the wire parallel mechanism that can be used to measure a full pose of a robot. It is composed of six parallel links using wire. The position and orientation of the end effectorf of a robot are calculated using the length of wires which is measured by the encoder. The complex non- linear equations of the forward kinematics are solved by using a numerical method, and the unique solution is obtained from the geometric configuration of the device. The length error of the wire which occurs in static condition is compensated by the relational equation that considered longitudinal extension and defoection of the wire. Through this work, we known that the proposed device has a good accuracy( .+-. 0.01mm) in a large measuring region, so it can be used effectively in a callibration of a robot which required a low cost.

• International Journal of Precision Engineering and Manufacturing
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• v.5 no.3
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• pp.54-61
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• 2004

This paper describes the development of a 6-axis robot's finger force/moment sensor, which measures forces $F_x$(x-direction force), $F_y$and $F_z$, and moments $M_x$ (x-direction moment), $M_y$ and $M_z$ simultaneously, for stable grasping of an unknown object. In order to safely grasp an unknown object using the robot's gripper, the force in the gripping direction and the force in the gravity direction should be measured, and the force control should be performed using the measured forces. Also, the moments $M_x$, $M_y$ and $M_z$ to accurately perceive the position of the object in the grippers should be detected. Thus, the robot's gripper should be composed of 6-axis robot's finger force/moment sensor that can measure forces $F_x$, $F_y$ and $F_z$, and moments $M_x$ $M_y$ and $M_z$ simultaneously. In this paper, the 6-axis robot's finger force/moment sensor for measuring forces $F_x$, $F_y$ and $F_z$, and moments $M_x$ $M_y$ and $M_z$ simultaneously was newly modeled using several parallel-plate beams, designed, and fabricated. The characteristic test of the fabricated sensor was performed, and the result shows that interference errors of the developed sensor are less than 3%. Also, Robot's gripper with the 6-axis robot's finger force/moment sensor for the characteristic test of force control was manufactured, and the characteristic test for grasping an unknown object using the sensors was performed using it. The fabricated gripper could grasp an unknown object stably. Thus, the developed 6-axis robot's finger force/moment sensor can be used for robot's gripper.