• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.2
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• pp.10-19
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• 1996

This paper presents a finger-shaped multisensor system which can measure the tyep and position of a target surface by contactl. The multi-sensor system consists of a sphere-shpaed optical tactile sensor located at the finger tip and a force/torque sensor located at the joint of a finger. The optial tactile sensor determines the type and position of the target surface using the shape and position of the CCD image of the touching area generated by a contact between the sensor and the taget surface. The force/torque sensor also determines the position and surface normal vector by applying the distributionof forces and torques t the contact point to the equations of finger shape. The measurements on the position and surface normal vector at a contact point obtined by two individual sensors are fused using a statistical method. The integrated sensor system has 0.8mm error in position measurement and 1.31$^{\circ}$ error in normal vector measurement. The developed sensor system has many applications, such as autonomous compliance control, automatic grasping and recognition, etc.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.12
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• pp.971-982
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• 1989

An integrating position estimation algorithm has been developed for the navigation system of a free-ranging AGV system. The navigation system focused in this research work consists of redundant wheel encoders for the relative position measurement and a vision sensor for the absolute position measurement. A maximum likelihood method and an extended Kalman filter are implemented for enhancing the performance of the position estimator. The maximum likelihood estimator processes noisy, redundant wheel encoder measurements and yields efficient estimates for the AGV motion between each sampling interval. The extended Kalman filter fuses inharmonious positional data from the deadreckoner and the vision sensor and computes the optimal position estimate. The simulation results show that the proposed position estimator solves a generalized estimation problem for locating the vehicle accurately in space.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.51 no.4
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• pp.187-194
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• 2002

Recently, the application of the linear machine far industrial field is remarkable increased, especially for the gantry machine, machine tool system and CNC. In these application fields, high dynamics position control performance Is essentially required in both the steady and the transient state. This pacer presents simple but powerful position control loop based on traditional PID controller. The presented position control algorithm, named 'Unified PID Position Controller'has great features for the linear machine drives such as no over-shoot phenomena and simple gain tuning strategy. Through the experimental results with commercial linear motors, it is shown that the proposed algorithm has excellent dynamics suitable fur linear motions.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.19 no.1
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• pp.25-29
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• 1989

The author has evaluated the panoramic image clarity of the midfacial anatomic structures in dry skull according to the skull position. The radiopaque markers were attached to the anatomic structures: infraorbial rim, upper and lower borders of zygomatic arch, pterygomaxillary fissure, lateral pterygoid plate, pyriform aperture of nasal cavity, lateral wall of maxilla, orbital floor, infraorbital foramen, and nasal floor. Position of the skull were divided into four groups. standard, 25mm forward, chin-down, chin-up position. The results were as follows: 1. The pyriform aperture of nasal cavity, lateral wall of the maxilla, orbital floor, infraorbital foramen and nasal floor did net cast any discernible image. 2. Nearly all images of midfacial structures were blurred in the chin-up position. 3. The forward position provided good visualization of the maxillary sinus. 4. The chin-down position provided good visualization of the zygomatic arch, pterygomaxillary fissue, and lateral pterygoid plate.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.575-578
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• 1995

In general, the control of robot manipulator is classified into position control and force control. Position controllers give adequate performance when a manipulator is following a trajectory through space and end-effector has no contact with environment. However for most tasks performed by robot manipulator in industry, contact is made between the end-effector and manipulator's environment, so position control may not suffice. The objective of this study is to control both position of a manipulator and the contact forces generated at the hand by using a conceptually simple control law. Position and force control problem is decoupled into subtasts via taskspace formulation and inverse dynamics. Then, the position controllers are designed for the task space variable which represent tangent motion and the forte controllers are designed for the lash space variables which represent normal force.

• Journal of Electrical Engineering and Technology
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• v.13 no.2
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• pp.829-837
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• 2018

In this paper, a flux linkage model based on four magnetization curves fitting is proposed for three-phase 12/8 switched reluctance motor (SRM), with the analysis of the basic principle of flux detection method and function analysis method. In the model, the single value function mapping relationship between position angle and flux is established, which can achieve a direct estimation of rotor position. The realization scheme of SRM indirect position detection system is presented. It is proved by simulation and experiment that the proposed scheme is suitable for rotor position detection of SRM, and has high accuracy of position estimation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.267-268
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• 2017

Obstructive sleep apnea in patients, between 70 and 80 percent, can be cured with just a posture correcting. It needed to know the current position information for correcting the position. The pressure sensors of the array type were used to obtain position information. These sensors can obtain information from the experimenter about position. In addition, air cylinder corrected the position of the experimenter by lifting the bed. The experimenter can be changed position without breaking during sleep by the system.

• Proceedings of the KIEE Conference
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• 1994.11a
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• pp.308-310
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• 1994

Position control for robot manipulator may not suffice when any contacts are made between the end-effector and various environments. Therefore interaction forces must be controlled in tasks performed by robot manipulator. In general, there are two types of force control for robot manipulator. One is a stiffness control and the other is a hybrid position/force control. Stiffness control is that environment can be modeled as a spring and utilizes the desired normal force to determine the desired normal position. Hybrid position/force control, however, can be used for robot manipulator to track position and force trajectories simultaneously. This paper will compare the result of the hybrid position/force control method with that of the stiffness control method.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.21 no.2
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• pp.235-248
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• 1991

This study was designed to evaluate the diagnostic effect of the simulatneous multifilm individualized lateral tomography in the diagnosis of the temporomandibular disorders. The subjects consisted of 29 patients with symptoms of the temporomandibular disorders. The panoramic view, oblique lateral transcranial radiograph (OLTC) (Hirozontal angulation 0°, Vertical angulation 29°), submentovertex view, and simultaneous multifilm individualized lateral tomographs (SMFI) in centric occlusion (2.5㎜ thickness difference, 5 layers) were taken for the patients. This study compared the findings from each radiographs in the determining of mandibular condylar position with dual linear measurement of the subjective closest posterior and subjective closest anterior interarticular space and in the determining of bony changes on the studied 30 temporomandibular joints (TMJ) with symptoms of the temporomandibular disorders. The results were as follows: 1. The distribution of condylar position of OLTC and 5 layers of SMFI depended on the radiographs (p<0.05). The condylar position and the distribution of condylar position of OLTC were more similar to lateral sections of the SMFI than mesial sections, and in the distribution of the condylar position of SMFI, the more lateral sections of SMFI, the more concentric 2. positions. There were 10 cases in which all layers showed the same condylar position as that of OLTC. There were 3 cases in which no layers showed the same condylar position as that of OLTC. 3. In the SMFI of 30 Temporomandibular joints studied, there is 13 cases in which all five layers represented the same condylar position in the same TMJ and 11 cases in which 4 layers represented the same condylar position in the same TMJ and 6 cases in which 3 layers represented the same condylar position in the same TMJ. So at least 3 layers of SMFI represented same condylar position in the same TMJ. 4. The bony changes were not detected in conventional radiographs on the temporomandibular joint and the bony changes were not detected in simultaneous multifilm individualized lateral tomographs. The bony changes were detected in conventional radiographs on the temporomandibular joint and the bony changes were detected in simultaneous multifilm individualized lateral tomographs. SMFI provided a meams for a three dimensional visualization of the shape, the position and the extent of bony changes of TMJ.

• The Korean Journal of Ecology
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• v.19 no.2
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• pp.107-123
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• 1996

The position effects on the abortion of flowers, fruits, and ovules were examined in relation to the resource limitation hypothesis using a temperate legume species, Vicia cracca. Fifty plants were randomly sampled from a natural population located at the Belmont Conservation Site in Belmont, MA, USA. Due to indeterminant growth and acropetal flowering of this species, the position of flower or fruit on the plant was able to be coded by the combination of architectural levels such as plant half (lower and upper half) and inflorescence half (lower and upper half) within each plant half. Overall, only 17.3% of the flowers on an inflorescence began to develop into fruits, while overall 36.0% of the fruits initiated failed to mature. Consequently, 11.5% of the flowers successfully matured into fruits. The mean flower number per inflorescence differed significantly among plants as well as between plant halves. Although the probability of fruit initiation was higher in the lower halves of both plant and inflorescence than in the upper halves of the latter, fruit abortion rate differed significantly only between plant halves. The overall mean seed set was 33.6%, implying that about two out of six ovules in a fruit matured into seeds. The seed set was independent of both plant identity and architectural level unlike other reproductive characters examined. When the ovule developmental stage was examined on data pooled over all fruits, the proportion of ovules in varying developmental stages decreased in order of early abortion, seed maturation, late abortion, and seed predation (48.4, 34.9, 12.2, and 4.5%, respectively). A within-fruit ovule position was also used as a class variable for the analysis of position effects on ovule development. All architectural levels considered exerted singificant influence over the ovule development. In particular, ovule development was strongly affected by the within-fruit ovule position. Ovules in both extreme ends within a fruit tended to abort early, while those in the middle position were more likely to mature into seeds. The strong position effects detected from the flowering to seed maturation stage were interpreted as an indication of competitive interaction among reproductive characters which are largely constrained by plant architecture.