• Title, Summary, Keyword: Smart Material

Search Result 745, Processing Time 0.047 seconds

Vibration control of laminated composite plates using embedded smart layers

  • Reddy, J.N.;Krishnan, S.
    • Structural Engineering and Mechanics
    • /
    • v.12 no.2
    • /
    • pp.135-156
    • /
    • 2001
  • Analytical solutions and finite element results of laminated composite plates with smart material layers embedded in them are presented in this study. The third-order plate theory of Reddy is used to study vibration suppression characteristics. The analytical solution for simply supported boundary conditions is based on the Navier solution procedure. The velocity feedback control is used. Parametric effects of the position of the smart material layers, material properties, and control parameters on the suppression time are investigated. It has been found that (a) the minimum vibration suppression time is achieved by placing the smart material layers farthest from the neutral axis, (b) using thinner smart material layers have better vibration attenuation characteristics, and, (c) the vibration suppression time is larger for a lower value of the feedback control coefficient.

Advanced Railway Vehicle Technology using Smart Materials (지능재료를 이용한 차세대 철도차량기술)

  • Kim, Jae-Hwan;Kang, Bu-Byoung;Kim, Kyeong-Jin;Chung, Heung-Chai;Choi, Sung-Kyu
    • Journal of the Korean Society for Railway
    • /
    • v.6 no.4
    • /
    • pp.252-256
    • /
    • 2003
  • Smart materials can adapt to changes of environment like living organs in nature such that they can maximize the performance and minimize the maintenance expense of engineering systems. Such materials have been paid attention ten years ago and applied in the area of industry, aerospace, transportation and civil structures. This paper summarizes smart material technology and shows some application examples in railway vehicles. Also, its future of smart material technology in railway vehicle technology is envisaged based on its possibility and practical aspect.

Smart body armor inspired by flow in bone

  • Tate, Melissa Louise Knothe
    • Smart Structures and Systems
    • /
    • v.7 no.3
    • /
    • pp.223-228
    • /
    • 2011
  • An understanding of biomaterials' smart properties and how biocomposite materials are manufactured by cells provides not only bio-inspiration for new classes of smart actuators and sensors but also foundational technology for smart materials and their manufacture. In this case study, I examine the unique smart properties of bone, which are evident at multiple length scales and how they provide inspiration for novel classes of mechanoactive materials. I then review potential approaches to engineer and manufacture bioinspired smart materials that can be applied to solve currently intractable problems such as the need for "smart" body armor or decor cum personal safety devices.

Development of High-Performance Smart Battery for Notebook PCs with Lithium Ion Battery (리튬이온전지를 이용한 노트북 PC용 고성능 Smart Battery의 개발)

  • 김현수;문성인;윤문수;고병희;김동훈
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.16 no.11
    • /
    • pp.1047-1054
    • /
    • 2003
  • Smart battery pack (SBP) for notebook PCs was developed using a cylindrical-type lithium ion battery. Batteries were connected with three serial and two parallel, the nominal capacity and the maximum load of SBP was 4,000mAh and 4.0A, respectively. The SBP was composed of a protection IC, by which safety of lithium ion batteries is maintained against overcharge, overdischarge and overcurrent, and a smart IC, which calculates the remaining capacity and the remaining run time. In matching test on notebook PC using Battery Mark 4.0, real and smart data of END voltage coincided nearly and LB and LLB signal worked norma]]y. And there were errors of less than 1% between the real and the smart data on the residual capacity in the charge and discharge test.

Development Estimation Method to Estimate Sensing Ability of Smart Sensors (지능센서의 센싱능력 평가를 위한 평가기법 개발)

  • Hwang Seong-Youn;Murozono Masahiko;Kim Young-Moon;Hong Dong-Pyo
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.15 no.2
    • /
    • pp.99-106
    • /
    • 2006
  • In this paper, the new method that estimates a sensing ability of smart sensor will be proposed. A study is estimation method that evaluates sensing ability about smart sensor respectively. According to acceleration(g) and displacement changing, we estimated sensing ability of smart sensor using SAI(Sensing Ability Index) method respectively. Smart sensors was made fer experiment. The types of smart sensor are two types(hard and soft smart sensor). Smart sensors developed for recognition of material. Experiment and analysis are executed for estimate the SAI method. In develop a smart sensor, the SAI method will be useful for finding optical design condition of smart sensor that can sense a material. And then dynamic characteristics of smart sensors(frequency changing, acceleration changing, critical point, etc.) are evaluated respectively through new method(SAI) that use the power spectrum density. Dynamic characteristic of sensor is evaluated with SAI method relatively. We can use the SAI for finding critical point of smart sensor, too.

Transmitted Noise Reduction of Piezoelectric Smart Panels using Passive/Active Method in Wide Range frequency (수동/능동적 방법을 혼용한 압전지능패널의 광대역 전달 소음저감성능)

  • 이중근;박우철
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.2 no.2
    • /
    • pp.73-79
    • /
    • 2001
  • In this paper, the transmitted noise reduction performance of piezoelectric smart panels is experimentally studied. The proposed piezoelectric smart panels are comprised of plate structure on which piezoelectric sensor/actuators are bonded and sound absorbing material is provided. It is a combination of passive and active approaches utilizing a passive effect at high frequencies and an active effect at low frequencies. To prove the concept of piezoelectric smart panels, an acoustic measurement experiment is performed. An acoustic tunnel is designed and its acoustic characteristics are tested. Below 800Hz, the tunnel exhibits a plane wave guide characteristics. When an absorbing material is bonded on a single plate, a remarkable transmitted noise reduction in mid frequency range is observed except the first resonance frequency. By enabling the active control of single smart panel with negative feedback control. about 10dB noise reduction is achieved at the resonance frequencies. The double smart panel got 4dB at the first resonance frequency and has more potential to reduce the transmitted noise in a wide range frequency. Piezoelectric smart panels incorporating passive absorbing material and active piezoelectric devices is a promising technology for noise reduction in a wide range frequency.

  • PDF

Development and Evaluation of Smart Pants with Vibrating Devices (진동장치를 이용한 기능성 스마트 팬츠 개발 및 평가)

  • Choi, Sun-Yoon;Lee, Jeong-Ran
    • Fashion & Textile Research Journal
    • /
    • v.11 no.1
    • /
    • pp.121-129
    • /
    • 2009
  • Nowadays, global interest is being placed on research and development of smart clothing which is expected to create a high added-value industry in the future. The purpose of this research is to develop smart pants with vibrating massage functions that have excellent outer appearances and provide comfort to wearers and assess outer appearance, comfort, and massaging effects of smart pants. As the results of this research, smart pants where vibrating devices which are mainly composed of vibrating motor, controller, and switch are attached were completed. Vibrating motors were fixed on a thin and light non-woven fabric material, covered with a mesh material, and attached by snaps to the experiment pants. Switch was attached to the inside of a pocket, and batteries were positioned inside of pockets. Ten subjects marked their satisfaction of wearing smart pants on a 5-point scale. Noticeable changes in outer appearance when vibrating motors operate turned out to be low. Wearer's comfort in back waist and front thigh parts where vibrating motors were attached turned out to be high-satisfied. Massaging effects of smart pants turned out to be high. Attaching and detaching vibrating devices turned out to be convenient. Lining materials used for smart paints were effective in blocking electromagnetic waves generated from vibrating devices.

Characteristics of Smart Skin for Wireless LAN system under Buckling Load (무선 랜 시스템용 스마트 스킨의 좌굴 특성 연구)

  • 전지훈;유치상;황운봉;박현철;박위상
    • Proceedings of the Korean Society For Composite Materials Conference
    • /
    • /
    • pp.42-45
    • /
    • 2001
  • The characteristics of smart skin for wireless LAN system under compression load are investigated. The smart skin structure is composed of 3 layers of face material and 2 layers of core material. Theoretical formula for determining buckling load is derived by Rayleigh-Ritz method and compared with experimental result. The maximum length of specimen that buckling does not occur is determined by only face material. In the experiment, if load supporting capability and the antenna property such as radiation pattern and reflection coefficient were examined.

  • PDF

Characteristics of smart skin under buckling load (스마트 스킨 구조물의 좌굴 특성 연구)

  • 전지훈;유치상;황운봉;박현철;박위상
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • /
    • pp.790-793
    • /
    • 2001
  • The characteristics of smart skin for wireless LAN system under compression load are investigated. The smart skin structure is composed of 3 layers of face material and 2 layers of core material. Theoretical formula for determining buckling load is derived by Rayleigh-Ritz method and compared with experimental result. The maximum length of specimen that buckling does not occur is determined by assuming that the compression load is sustained by only face material. In the experiment, if buckling occurs obviously then it follows the theoretical result well. In the process of buckling, the load supporting capability and the antenna property such as radiation pattern and reflection coefficient were examined.

  • PDF

Damage detection on two-dimensional structure based on active Lamb waves

  • Peng, Ge;Yuan, Shen Fang;Xu, Xin
    • Smart Structures and Systems
    • /
    • v.2 no.2
    • /
    • pp.171-188
    • /
    • 2006
  • This paper deals with damage detection using active Lamb waves. The wavelet transform and empirical mode decomposition methods are discussed for measuring the Lamb wave's arrival time of the group velocity. An experimental system to diagnose the damage in the composite plate is developed. A method to optimize this system is also given for practical applications of active Lamb waves, which involve optimal arrangement of the piezoelectric elements to produce single mode Lamb waves. In the paper, the single mode Lamb wave means that there exists no overlapping among different Lamb wave modes and the original Lamb wave signal with the boundary reflection signals. Based on this optimized PZT arrangement method, five damage localizations on different plates are completed and the results using wavelet transform and empirical mode decomposition methods are compared.