• Title/Summary/Keyword: Automatic Driving

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The SOTDMA Algorithm Development and Verification for AIS (AIS용 SOTDMA알고리즘 구현 및 검증에 관한 연구)

  • Lee, Sang-Hoey;Lee, Hyo-Sung;Lim, Yong-Kon;Lee, Heung-Ho
    • Proceedings of the KIEE Conference
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    • 2005.07d
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    • pp.3037-3039
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    • 2005
  • The AIS(Automatic Identification System) transmits the position of ships and other information to prevent accidents which could occur in the sea. It has to be developed SOTDMA(Self-Organized Time Division Multiple Access) Algorithm which is important on wireless communication method for the AIS because It is based on ITU(International Telecommunication Union) M.1371-1 of the international standard therefore, we need to develop a performance evaluation simulator efficiently to develop and analyze SOTDMA Algorithm. this paper shows the method of designing it. Real ships access The VHF maritime mobile band but in this performance evaluation simulator several ship objects access the shared memory. Real ships are designed as the object and the wireless communication channel is designed as the shared memory. The ships apply for real virtual data which got from assistance hardware and The SOTDMA Algorithm driving state verifies the performance evaluation simulator by IEC(International Electrotechnical commission) 61993-2. After verifying results the performance evaluation simulator is correctly satisfied with IEC 61993-2. So we expect that it helps not only the AIS technology developed but also verify new SOTDMA Algorithm

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Performance of a 2 Room Multi-Heat Pump with a Constant Speed Compressor

  • Kwan Young Chul;Kwon Jeong-Tae;Jeong Ji Hwan;Lee Sang Jae;Kim Dae Hun
    • International Journal of Air-Conditioning and Refrigeration
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    • v.12 no.4
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    • pp.184-191
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    • 2004
  • In order to improve the performance of a 2 room heat pump with a constant speed compressor, the optimum refrigeration circuit of the heat pump with different cooling and heating capacities is developed by applying capillary tubes. The refrigeration circuit is composed of four parts; a heating circuit, a cooling circuit, a by-pass circuit and a balance circuit. The performance of the 2 room heat pump are investigated from a rating experiment and a reliability experiment, using the calorimeter. Results of the rating experiment show that the capacity of heat pump is about $93\%$ of the design value. In particular, the capacity of the cooling single operation is about $13\%$ higher than the design value, and the capacity of the heating multi operation is about $5\%$ higher than the design value. From the reliability experi-ment, it is found that the lowest driving voltage of the compressor is about $75\%$ of the rating voltage. Also the compressor is reoperated normally under the flood back and the over load.

Development of Simulator for AIS Algorithm Verification (AIS 알고리즘 검증용 시뮬레이터 개발)

  • Lee, Hyo-Sung;Lee, Seung-Min;Lee, Heung-Ho
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.478-480
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    • 2005
  • The AIS(Automatic Identification System) transmits the position of ships and other information to prevent accidents which could occur in the sea. It has to be developed SOTDMA(Self-Organized Time Division Multiple Access) Algorithm which is important on wireless communication method for the AIS because It is based on ITU(International Telecommunication Union) M.1371-1 of the international standard therefore, we need to develop a performance evaluation simulator efficiently to develop and analyze SOTDMA Algorithm. This paper shows the method of designing it. Real ships access The VHF maritime mobile band but in this performance evaluation simulator several ship objects access the shared memory. Real ships are designed as the object and the wireless communication channel is designed as the shared memory. The ships apply for real virtual data which got from assistance hardware and The SOTDMA Algorithm driving state verifies the performance evaluation simulator by IEC(International Electrotechnical commission) 61993-2. After verifying results the performance evaluation simulator is correctly satisfied with IEC 61993-2. So we expect that it helps not only the AIS technology developed but also verify new SOTDMA Algorithm.

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System dynamics of scanning tunneling microscope unit

  • Yamada, Hikaru;Endo, Toshiro;Tsunetaka-Sumomogi;Fujita, Toshizo;Morita, Seizo
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10b
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    • pp.794-797
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    • 1988
  • G. Binnig and H. Rohrer introduced the Scanning Tunneling Microscope (STM) in 1982 and developed it into a powerful and not to be missed physical tool. Scanning tunneling Microscopy is a real space surface imaging method with the atomic or subatomic resolution in all three dimensions. The tip is scanned over the surface by two piezo translators mounted parallel (X-piezo and Y-piezo) to the surface and perpendicular to each other. The voltage applied to the third piezo (Z-piezo) translator mounted perpendicular to the surface to maintain the tunneling current through the gap at a constant level reflects then the topography of the surface. The feed back control loop for the constant gap current is designed using the automatic control technique. In the designing process of the feed back loop, the identification of the gap dynamics is very complex and has difficulty. In this research, using some suitable test signals, the system dynamics of the gap including the Z-piezo are investigated. Especially, in this paper, a system model is proposed for the gap and Z-piezo series system. Indicial response is used to find out the model. The driving voltage of the Z-piezo and the tunneling current are considered as input and output signals respectively.

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A Study on the Seam Tracking Behavior for container box's welding (컨테이너박스용 용접선 추적거동에 관한 연구)

  • Ahn, Byong-Won;Bae, Cherl-O;Kim, Hyun-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • v.30 no.3
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    • pp.438-443
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    • 2006
  • The probe type sensor using strain gauges was used to track a container box's seam in this paper. A strain gauge has a property which the specific resistance is changed by varying of the sectional area and length when tensile and compressive stresses are generated at the strain gauge. We designed the automatic seam tracking device by attaching the probe type strain gauge sensor, motor driving slide, encorder to check the moving distance and interface card connected MPU upside the speed controllable carriage. The folded work piece for a container box is made to examine whether the device can track the seam automatically or not. Seam tracking experiments were done by changing the carriage moving speed at 300. 400. 500. 600[mm/min] each as the voltage of side track was 2.5[V]. We compared and analyzed the sampling data which is obtained by output voltage of strain gauge sensor and rotary encorder pulse every 100 [m/s]. The welding experiments were performed by using $CO_2$ welding machine about the carriage moving speed that has good seam tracking condition in the seam tracking experiments above. And we compared the seam tracking status.

A Study on the Development of a Corrupad Rewinding Machine with Eccentric Cantilever Structure (편심 외팔보 구조의 코러패드 재권취기 개발에 관한 연구)

  • 김강은;이종호;신대영;이우영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2003.06a
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    • pp.1609-1613
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    • 2003
  • This research focused on the development of automatically exclusive production equipment of corrupad as changing manual system into automatic system to increase the output. Therefore the minimization of the problem of the rewinding mechanism with eccentric cantilever structure is key to the achievement of the high performance for automation production. Proto-type corrupad rewinding machine is manufactured after considering the effect of the rotational vibration and natural frequency of the structure of machine by using 3D design packages such as ADAMS and I-deas. For evaluating the performance of the proto-type machine, simulations of dynamic and static characteristics using 3D design packages, a series of modal tests by accelerometer and measurements of dynamic behavior by high-speed camera for rewinding part, were carried out. As a result, the proto-type machine was not affected with the rotational vibration. Whirling error of eccentric cantilever structure in driving is small. Therefore the machine developed is most suitable to produce corrupad automatically. However reinforcement of the structure in axial direction is required due to so vibration in that direction.

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Water Quality Control System Development for Cooling Towers (냉각탑 수질관리를 위한 자동화 시스템 개발)

  • Lee, Ki-Keon;Song, Moo-Jun;Lee, Young-Jae;Sung, Sang-Kyung;Kang, Tae-Sam
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.1
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    • pp.36-41
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    • 2008
  • Cooling tower is an important equipment of the cooling systems for large buildings like factory and department store. Water used for cooling in cooling tower is reused continuously. If the water is polluted, corrosion and scale can happen at equipments and pipes. In order to prevent this problem, it is necessary to control the water quality using chemicals. To control the water quality, an automatic control system is designed, fabricated, and experimented. The control system is based on an imbedded microcontroller. Relays are used for power driving, an LCD and LED for display, and RS485 for remote data acquisition. Monitoring program is also developed for easy man-machine interface and extraction of data stored in the imbedded processor and EEPROM. The control system calculates amounts of chemicals necessary using sensor data and injects the chemicals into the cooling tower on proper time. The developed water quality control system is expected to reduce cost of maintenance and extend the lifetime of the cooling systems with low cost.

Convergence Analysis of Kinematic Parameter Calibration for a Car-Like Mobile Robot (차량형 이동로봇의 기구학적 파라미터 보정을 위한 수렴성 분석)

  • Yoo, Kwang-Hyun;Lee, Kook-Tae;Jung, Chang-Bae;Chung, Woo-Jin
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.12
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    • pp.1256-1265
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    • 2011
  • Automated parking assist systems are being commercialized and rapidly spread in the market. In order to improve odometry accuracy, we proposed a practical odometry calibration scheme of Car-Like Mobile Robot (CLMR). However, there were some open problems in our prior work. For example, it was not clear whether the kinematic parameters always converged or not using the proposed calibration scheme. In addition, test driving had to be carried out "twice" without detailed explanation. This research aims to provide answers for the addressed questions though the convergence property analysis of the calibration scheme. In this paper, we evaluate on the effect of the kinematic parameter error on the odometry error at the final pose by numerical computation. The evaluation will show that the wheel diameter and tread of the CLMR can be calibrated by iterative test drives. In addition, the region of convergence in the parametric space will be discussed. Presented experimental results clearly showed that the proposed calibration scheme would be useful in practical applications.

A Study on the Automatic Fuel-Filling-Recognition system for a city bus (자동인식 주유량 처리 시스템에 관한 연구)

  • 김현수;안병원;박중순;박영산;배철오;김철홍
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.414-417
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    • 2001
  • In this paper the fuel filling system for a city bus was investigated in order to improve the system. The suggested fuel filling system was designed to have functions of identifying a bus arrival tine, and measuring volume of fuel filled. The system consisted of four parts of bus identification, IBM PC, interface card, fuel filling control system and program for integrating all parts. It is believed that the information obtained by this system can be used for analysing driver's driving habits and performance of engine of a bus, and accordingly the prime cost can be reduced.

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Study on Automation of Integrated Seedling Production System - Planting Device- (종합공동육묘장의 설비 자동화에 관한 연구 -파종시스템-)

  • 최창현;노광모;이규창;김재민
    • Journal of Biosystems Engineering
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    • v.21 no.2
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    • pp.123-133
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    • 1996
  • An automatic drum seeder was developed to improve the seeding operation. It consisted of a conveyor to transfer seedling trays, a seed-hopper to supply seeds, a drum to drop seeds on the tray, and an air blower to remove extra seeds. A photo sensor was used to detect the transfer of seedling trays, and its signal was fed into microcomputer which operated a stepping motor driving the drum. The seeds were adhered to the surface of drum by vacuum pressure, and were dropped into tray cells by compressed air. An air connection unit was devised to alternate between vacuum pressure and compressed air. A control program for the system, written in C language, could operate the drum at the given number of revolutions and revolutions per minute. The results showed that the air connection unit could operate well and the seeds were dropped satisfactorily into tray cells. In case of cabbage and perilla seeds, which are regular and spherical shape, the missing rate was low and the single seeding rate was more than 97%. Low missing rate and high multiple seeding rate were observed in lettuce seeds which have narrow ends with tight weight. The missing rate of pepper seed was very high because of heavy weight and irregular shape. To improve the performance of the seeder, adjustment of vacuum pressure based upon shape and weight of the seeds, careful selection of the material of drum, maintenance of consistent air blower pressure, and replacement of stepping motor to DC motor are recommended.

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