• Title/Summary/Keyword: Slip system

Search Result 919, Processing Time 0.023 seconds

Slip-Related Changes in Plantar Pressure Distribution, and Parameters for Early Detection of Slip Events

  • Choi, Seungyoung;Cho, Hyungpil;Kang, Boram;Lee, Dong Hun;Kim, Mi Jung;Jang, Seong Ho
    • Annals of Rehabilitation Medicine
    • /
    • v.39 no.6
    • /
    • pp.897-904
    • /
    • 2015
  • Objective To investigate differences in plantar pressure distribution between a normal gait and unpredictable slip events to predict the initiation of the slipping process. Methods Eleven male participants were enrolled. Subjects walked onto a wooden tile, and two layers of oily vinyl sheet were placed on the expected spot of the 4th step to induce a slip. An insole pressure-measuring system was used to monitor plantar pressure distribution. This system measured plantar pressure in four regions (the toes, metatarsal head, arch, and heel) for three events: the step during normal gait; the recovered step, when the subject recovered from a slip; and the uncorrected, harmful slipped step. Four variables were analyzed: peak pressure (PP), contact time (CT), the pressure-time integral (PTI), and the instant of peak pressure (IPP). Results The plantar pressure pattern in the heel was unique, as compared with other parts of the sole. In the heel, PP, CT, and PTI values were high in slipped and recovered steps compared with normal steps. The IPP differed markedly among the three steps. The IPPs in the heel for the three events were, in descending order (from latest to earliest), slipped, recovered, and normal steps, whereas in the other regions the order was normal, recovered, and slipped steps. Finally, the metatarsal head-to-heel IPP ratios for the normal, recovered, and slipped steps were $6.1{\pm}2.9$, $3.1{\pm}3.0$, and $2.2{\pm}2.5$, respectively. Conclusion A distinctive plantar pressure pattern in the heel might be useful for early detection of a slip event to prevent slip-related injuries.

Implementation of a soap based web services for slip data process (전표데이터 처리를 위한 SOAP기반 웹서비스의 구현)

  • 황의철;정민영;정선태
    • Proceedings of the IEEK Conference
    • /
    • 2003.07d
    • /
    • pp.1435-1438
    • /
    • 2003
  • SOAP(Simple Object Access Protocol) that is a late protocol for exchange of information with Web Services that is useful for implementing common functions in especially a large size business area, is a protocol that is a lightweight, XML-based protocol over HTTP for exchange to information in decentralized, distributed environments. In this paper, we implement SOAP-based Web Services that can use with a slip database, for common slip processing functions in enterprise accounts in order to enhance the transparency of transactions by slip processing system. The result of this paper will contribute to increasing the productivity of enterprises through enhancing the standardization of slip data, reusability of functions, convenience of access, and efficiency of implementing applications.

  • PDF

A New Method Calculating Total Slip of Fault with Fault Separation (단층변위를 이용한 단층의 총 이동량 계산법)

  • Hwang, Jae Ha
    • Economic and Environmental Geology
    • /
    • v.31 no.6
    • /
    • pp.547-555
    • /
    • 1998
  • A new trigonometrical method for calculating total slip (T) of faulting is presented. The parameters for the calculations are used rake of fault striation, strike and dip of fault and of index planar structure such as bedding plane. The faults are groupped into three types. The direction of plunging of fault striation is out of a range ${\pm}90^{\circ}$ to the bedding dip direction in $360^{\circ}$ system, which is groupped into the type I. Meanwhile, the case of the direction lies in the above range can be separated into two different types, type II and type III, according to relative largeness of the angles rake of fault striation and i (see text). The type II has smaller rake than angle i and the type III has larger rake than angle i. Here I propose a few equations for calculating not only total slip (T) but strike slip (L) or dip slip (S) of the faulting. The equations are adapted selectively to the types of fault mentioned before. The limitation of the method is that the equations do not fit to polyphase faulting.

  • PDF

Sliding Mode Control for a High-Load Wheeled Mobile Robot (중하중을 받는 이동로붓의 슬라이딩모드 제어)

  • 홍대희;정재훈
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.17 no.5
    • /
    • pp.145-153
    • /
    • 2000
  • This paper discusses the dynamic modeling and robust control development for a differentially steered mobile robot subject to wheel slip according to high load. Consideration of wheel slip is crucial for high load applications such as construction automation tasks because wheel slip acts as a severe disturbance to the system. It is shown that the uncertainty terms due to the wheel slip satisfy the matching condition for the sliding mode control design. From the full dynamic model of the mobile robot, a reduced ideal model is extracted to facilitate the control design. The sliding mode control method ensures the dynamic tracking performance for such a mobile robot. Numerical simulation shows the promise of the developed algorithm.

  • PDF

Rheological Properties of Si3N4 Suspension and Microstructure of Slip Cast Si3N4 (Si3N4의 슬립물성과 Slip Cast Si3N4의 미세구조에 관한 연구)

  • 박정현;김진숙;박한수
    • Journal of the Korean Ceramic Society
    • /
    • v.25 no.6
    • /
    • pp.615-622
    • /
    • 1988
  • To develope good slip and microstructure of Si3N4 the knowledge of the interaction of particles in liquid systems is required. In this work polyethyleneimines was tested as a stabilizer for Si3N4-water system. The stability of slip dispersed with polyethyleneimines was good over a wide range of pH and concentrated slips with low viscosity could be cast. This work comprises a systematic investigation including determination of electrical mobility in order to estimate the particle surface charge, determination of sedimentation rate, as well as measurements of the viscosity as a function of dispersants, pH and shear rates. The influence of deflocculation on the microstructure of slip cast Si3N4 was discussed.

  • PDF

Finite Element Stress Analysis of Implant Prosthesis According to Friction Fit or Slip Fit of Internal Connection System between Implant and Abutment (임플랜트와 지대주 간 내측연결 시스템에서 Friction Fit와 Slip Fit에 따른 유한요소 응력분석)

  • Jang, Doo-Ik;Jeong, Seung-Mi;Chung, Chae-Heon
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.21 no.2
    • /
    • pp.113-132
    • /
    • 2005
  • The purpose of this study was to assess the stress-induced pattern at the supporting bone, the implant fixture, the abutment and the abutment screw according to a friction-fit joint (Astra; Model 1) or slip- fit joint (Frialit-2; Model 2) in the internal connection system under vertical and inclined loading using finite element analysis. In conclusion, in the internal connection system of the implant and the abutment connection methods, the stress-induced pattern at the supporting bone, the implant fixture, the abutment and the abutment screw according to the abutment connection form had difference among them, and the stress distribution pattern usually had a widely distributed tendency along the inner surface of the implant fixture contacting the abutment post. The magnitude of the stress distributed in the supporting bone, the implant fixture, the abutment and the abutment screw was higher in the friction-fit joint than in the slip-fit joint. But it is considered that the further study is necessary about how this difference in the magnitude of the stress have an effect on the practical clinic.

A Study on Relationship between Curving Noise and Wheel Wear in Seoul Subway System (지하철 곡선부소음과 차륜 마모와의 관계에 관한 연구)

  • You, Won-Hee;Hur, Hyun-Moo;Koh, Hyo-In;Park, Joon-Hyuk;Choi, Yong-Woon
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.19 no.1
    • /
    • pp.85-93
    • /
    • 2009
  • There are many curves in Seoul subway system. Therefore, the noise from subway system in curved line gives displeasure to passenger. The subway noise in curved line is affected not only by rail condition but also wheel condition and dynamic characteristics. The railway curving noise can be divided into 2 categories. The first is the noise due to stick-slip between wheel tread and rail head, and the second is one by wheel flange contact on rail side. Because of these phenomena - stick-slip and wheel flange contact - wheels are worn seriously. In this study the curving noise was reviewed by using eigen-mode of wheel and waterfall plot which shows noise level in time-frequency domain. And also those were reviewed in viewpoint of stick-slip noise and wheel flange contact noise. Finally, the relationship between curving noise and wheel wear was studied.

Neural network based position estimation of mobile robot in slippery environment (Slip이 발생할 때 신경회로망을 이용한 이동로보트의 위치추정에 관한 연구)

  • 최동엽;조형석
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1993.10a
    • /
    • pp.133-138
    • /
    • 1993
  • This paper presents neural network based position estimation method in slippery environment as an approach to solve one of problems which are engaged in dead reckoning method. Position estimator is composed of slip detector and linear velocity estimator. Both of them are based on the fact that dynamic characteristic of mobile robot in slippery environment is different from the case without slip. To find out the dynamic relation among driving torque, angular acceleration of driving wheel and linear acceleration of mobile robot, accelerometer is used for measuring acceleration of mobile robot and neural network is used for dynamic system identifier in slippery environment.

  • PDF

A Study on Integrated Control of AFS and ARS Using Fuzzy Logic Control Method (Fuzzy Logic 제어를 이용한 AFS와 ARS의 통합제어에 관한 연구)

  • Song, Jeonghoon
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.22 no.1
    • /
    • pp.65-70
    • /
    • 2014
  • An Integrated Dynamics Control system with four wheel Steering (IDCS) is proposed and analysed in this study. It integrates and controls steer angle of front and rear wheel simultaneously to enhance lateral stability and steerability. An active front steer (AFS) system and an active rear steer (ARS) system are also developed to compare their performances. The systems are evaluated during brake maneuver and several road conditions are used to test the performances. The results showed that IDCS vehicle follows the reference yaw rate and reduces side slip angle very well. AFS and ARS vehicles track the reference yaw rate but they can not reduce side slip angle. On split-${\mu}$ road, IDCS controller forces the vehicle to go straight ahead but AFS and ARS vehicles show lateral deviation from centerline.