• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.2
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• pp.43-48
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• 2012

In this paper, we present the method of gait phases detection using multi biomedical signals during normal gait. Electromyogram(EMG) signals, muscle of thigh angle measurement device and resistive sensors are used for experiments. We implemented a test targeting five adult male and identified the pattern of EMG signal of normal gait. For acquiring the EMG signal, subjects attached surface Ag/AgCl electrodes to quadriceps femoris, biceps femoris, tibialis anterior and gastrocnemius medialis. Resistance sensors are attached to the heel toe and soles of the each feet for measuring attachment state of between feet and ground. Infrared sensors are attached on the thigh and thigh angle measurement device has the range from flection 25 degrees to extension 20 degrees. The results of this paper, The stance and swing phase could be confirmed during the normal gait and be classified in detail the eight steps.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.2
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• pp.124-129
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• 2013

Hexapod walking robots are superior to biped or quadruped ones in terms of walking stability. Therefore hexapod robots have the advantage in performing intelligent tasks based on walking stability. In this paper, we propose a hexapod robot that has one fore leg, one hind leg, two left legs, and two right legs and can perform various intelligent tasks. We build the robot by using 26 motors and implement a controller which consists of a host PC, a DSP main controller, an AVR auxiliary controller, and smart phone/pad. We show by several experiments that the implemented robot can perform various intelligent tasks such as uneven surface walking, tracking and kicking a ball, remote control and 3D monitoring by using data obtained from stereo camera, infrared sensors, ultra sound sensors, and contact sensors.

• Journal of Satellite, Information and Communications
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• v.12 no.3
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• pp.15-21
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• 2017

Following the successful launch of KOMPSAT-3 in May 2012, KOMPSAT-5 in August 2013, and KOMPSAT-3A in March 2015 have succeeded in launching the integrated operation of optical, radar and thermal infrared sensors in Korea. We have established a foundation to utilize the characteristics of each sensors. In order to overcome limitations in the range of application and accuracy of the application of a single sensor, multi-sensor image fusion techniques have been developed which take advantage of multiple sensors and complement each other. In this paper, we introduce the development of software (InFusion) for multi-sensor image fusion and valued-added product generation using KOMPSAT series. First, we describe the characteristics of each sensor and the necessity of fusion software development, and describe the entire development process. It aims to increase the data utilization of KOMPSAT series and to inform the superiority of domestic software through creation of high value-added products.

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.59-65
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• 2010

Many Construction companies are making great efforts to prevent accidents on their work sites. Safety is one of the greatest success factors on a construction project. Nowadays, many safety tools are being applied to construction sites. In addition, an emotional safety culture is an important factor for promoting a "safety first" mindset on construction sites. Therefore, this research aims to examine the effectiveness of the emotional safety system using PIR (Pyroelectric Infrared Ray) sensors to improve the safety mindset in the building construction site. The results of this research revealed that many construction site workers are satisfied with the emotional safety system using sensors. In addition, it was found that voice safety systems give a positive impulse to the workers. By applying this system to construction sites, construction companies can improve safety and work productivity.

• Journal of Biomedical Engineering Research
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• v.41 no.3
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• pp.121-127
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• 2020

The purpose of this paper is to review the validation on the application of low frequency IMU(Inertial Measurement Unit) sensors by replacing high frequency motion analysis systems. Using an infrared-based 3D motion analysis system and IMU sensors (22 Hz) simultaneously, the gait cycle and knee flexion angle were measured. And the accuracy of each gait parameter was compared according to the statistical analysis method. The Bland-Altman plot analysis method was used to verify whether proper accuracy can be obtained when extracting gait parameters with low frequency sensors. As a result of the study, the use of the new gait assessment system was able to identify adequate accuracy in the measurement of cadence and stance phase. In addition, if the number of gait cycles is increased and the results of body anthropometric measurements are reflected in the gait analysis algorithm, is expected to improve accuracy in step length, walking speed, and range of motion measurements. The suggested gait assessment system is expected to make gait analysis more convenient. Furthermore, it will provide patients more accurate assessment and customized rehabilitation program through the quantitative data driven results.

• Journal of Engineering Education Research
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• v.8 no.1
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• pp.5-19
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• 2005

This paper describes the design and fabrication of magnetic levitation kits for use in the hands on experiments of automatic control, digital control and microprocessor applications in the division of mechatronics in Samcheok university. The kits are developed inspired by MIT's design, but it is designed on the digital basis, whereas MIT's is designed on the analog basis. As a result, the kits can be monitored and controlled on the analog and digital control techniques. Furthermore, the cost of kit components is comparable or lower to that of MIT design. And the kits can be controlled with magnetic hall sensors and/or infrared sensors, which provides more versatile experience on the use of sensors and signal filtering to the students. The design is fabricated and tested by authors and will be provided to the students as lab projects. The kits will be intentionally presented with a device that is poorly instrumented and poorly compensated. And the students are expected to analyze sensor signal and controller performance, and then, perform compensator design and signal filtering.

• Journal of Korean Society for Geospatial Information Science
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• v.23 no.1
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• pp.81-88
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• 2015

Various satellite sensors having ranges of the visible, infrared, and thermal wavelengths have been launched due to the improvement of hardware technologies of satellite sensors development. According to the development of satellite sensors with various wavelength ranges, the fusion and integration of multisensor images are proceeded. Image matching process is an essential step for the application of multisensor images. Some algorithms, such as SIFT and SURF, have been proposed to co-register satellite images. However, when the existing algorithms are applied to extract matching points between optical and thermal images, high accuracy of co-registration might not be guaranteed because these images have difference spectral and spatial characteristics. In this paper, location of control points in a reference image is extracted by SURF, and then, location of their corresponding pairs is estimated from the correlation of the local similarity. In the case of local similarity, phase correlation method, which is based on fourier transformation, is applied. In the experiments by simulated, Landsat-8, and ASTER datasets, the proposed algorithm could extract reliable matching points compared to the existing SURF-based method.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.1
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• pp.78-83
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• 2007

Robot collects surrounding information to recognize tile unknown environment by using various sensors such as visual, infrared ray and ultra sonic sensors. Although visual sensor is the most popular one, it has some difficulties in collecting data in dark or too bright environment due to sensitivity of the light. It also requests significant amount of calculation on collecting data from certain images with marked, straight and curved ones. As an alternative, ultra sonic sensor can simply overcome this visual sensing system's flaw and easily be used. It is easier than visual system, especially in case of collecting data on object and distance in dark environment. Ultra sonic sensor can replace the expensive visual sensing system not only in avoiding obstacles but also in reaching to the target area smoothly. The purpose of this paper is to develop the algorithm to optimize the environmental recognition, path planning and free-ranging by minimizing errors caused by inaccurate information and by considering characteristics of the ultra sonic rays such as refraction and diffusion. This paper also realizes the system that can recognize the environment and make the appropriate path planning by applying the algorithm on this moving robot.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.3
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• pp.577-592
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• 2023

In this study, nanofiber-based textile sensors were developed for motion detection and monitoring. Poly(vinylidene fluoride) (PVDF) nanofibers containing zinc oxide (ZnO) nanoparticles and silver nanowires (AgNW) were fabricated using electrospinning. PVDF was chosen as a piezoelectric polymer, zinc oxide as a piezoelectric ceramic, and AgNW as a metal to improve electric conductivity. The PVDF/ZnO/AgNW nanocomposite fibers were used to develop a textile sensor, which was then incorporated into an elbow band to develop a wearable smart band. Changes in the output voltage and peak-to-peak voltage (V_p-p) generated by the joint's flexion and extension were investigated using a dummy elbow. The β-phase crystallinity of pure PVDF nanofibers was 58% when analyzed using Fourier transform infrared spectroscopy; however, the β-phase crystallinity increased to 70% in PVDF nanofibers containing ZnO and to 78% in PVDF nanocomposite fibers containing both ZnO and AgNW. The textile sensor's output voltage values varied with joint-bending angle; upon increasing the joint angle from 45° to 90° to 150°, the V_p-p value increased from 0.321 V_p-p to 0.542 V_p-p to 0.660 V_p-p respectively. This suggests that the textile sensor can be used to detect and monitor body movements.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2010.11a
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• pp.18-20
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• 2010

본 논문에서는 3차원 모니터를 시청하는 시청자의 위치를 추적한 후 시청위치에 따라 다른 시점의 영상을 제공하는 시스템을 제안한다. 본 시스템은 센서들의 신호를 제어하는 CPU, 3개의 초음파센서, 1개의 PIR(Passive infrared radiation)센서, 센서별 신호를 분기해주는 PLD(programmable logic device)로 구성되어 있다. 3개의 초음파 센서를 이용해 20개의 탐색구역 내에 있는 시청자의 정확한 위치를 추적한다. 시스템을 구현한 결과 전방 5m, 좌우 3m의 탐색범위 내에서 시청자의 위치를 정확히 추적하여 해당 시점의 영상을 디스플레이 하였다.