Research 

Novel Structure Design for Acoustics and Vibrations 

Metamaterials (or meta-structures) are engineered materials consisting of subwavelength structures. Based on intelligent design and manufacturing, we can manipulate basic mechanical parameters such as the bulk modulus (B) and mass density (ρ). Due to exotic design configurations, negative density or stiffness, not commonly found in natural materials, can be achieved by expanding the parameter space of materials. Thus, these smart materials provide the new acoustic/vibration solutions which conventional methods cannot address. In our laboratory, we develop novel structures and devices for mechanical application systems such as vibration/noise reduction, acoustic & ultrasonic sensor, impact protection and energy harvesting, etc. 

Research Topic 

1. 음향/진동 제어를 위한 스마트 구조 설계   (Smart Structural Design for Acoustic/Vibration Control)

     √  음향증폭스마트구조 (Sound Amplification)

   √  진동에너지 하베스팅 (Vibration/Acoustic Energy Harvesting) 

 K. Song , K.Kim, S.Hur, J.Kwak, J.Park, J.Yoon, J.kim, Sound Pressure Level Gain in an Acoustic Meta-material Cavity, Scientific Reports  4, 7421,  2014 

 K. Song, S.Lee, K.Kim, S.Hur and J.Kim, Emission Enhancement of Sound Emitters using an Acoustic Metamaterial Cavity, Scientific Reports 4, 4165, 2014 

 K. Sun, J.E. Kim, J. Kim, K. Song, Sound energy harvesting using a doubly coiled-up acoustic metamaterial cavity, Smart Materials and Structures,  26, 075011, 2017 

2. 기계 제품 소음/진동저감  설계 (Machine noise reduction  through Metastructure design)

     √  냉장고/건조기/청소기 소음저감 연구  

     √  스마트메타물질적용 가전제품 소음저감연구 

K.An, H, Kwon, J.Jang, K.Song, Acoustic Metamaterial Design for Noise Reduction in Vacuum Cleaner, 36(6):1-10, 2022. Journal of Mechanical Science and Technology

3 . 기계소음 저감을 위한 스마트 구조 설계  (Machine noise reduction  through Smart  design) 

         √  극한물성 제어 기술 (Design of Extreme Material properties) :  극한밀도/극한 탄성률 /극한 임피던스,  3D 프린팅 기반 극한물성메타구조  설계 

        √  초박형  차음재/흡음재 ( (Ultrathin soundproofing/Absorbing   Material) : 메타구조 기반 흡차음재 디자인, 잠수함 적용 수중 스텔스 기술 

        √  메타구조 기반 음향 사일런스 : 음향 블랙홀기반 사일런스 설계,  Maze 구조 기반 사일런스 설계, 적층 제조 기술기반 사일런스 제작

        √  진동에너지 저감 구조 설계 저주파 진동 저감 구조 설계 

J.Jang, K.Song, Synergistic Acoustic Metamaterial for Soundproofing: Combining Membrane and Locally Resonant Structure, 256, 108500, 2023. International Journal of Mechanical Sciences 

J. Jang, C Park, K. Song , Lightweight soundproofing membrane acoustic metamaterial for broadband sound insulation, Volume 178, 1 October 2022, 109270, Mechanical Systems and Signal Processing 

 J.Park, J.Kwak, K. Song, Ultraslow medium with an acoustic membrane-like undamped dynamic vibration absorber for low-frequency isolation, vol 43, 101203, 2021, Extreme Mechanics Letter 

4 . 진동/소음  시뮬레이션 및 측정 기술  

          √  시뮬레이션 기반  진동/소음 예측 시뮬레이션 

          √  머신런닝&인공지능 기반  진동/소음 시뮬레이션 

          임피던스튜브 기반  흡음률/투과율 측정 

         √  진동/소음 무향실 기반 소음/진동 측정기술 

5스마트 구조 기반 음향/진동 제어기술  (Smart Acoustic/Vibration Control Technology)

        •  지향성  음향안테나 설계 기술 

       •  홀로그램 메타표면 설계기술

       •  홀로그램기반 두개골 투과 메타물질 기술 개발 

M. Akram, J.Jang, K.Song,  Directional Enhancement of Triangular Holographic Acoustic Leaky-Wave Antennas with Reflectors, 2024. International Journal of Mecanical Sciences

M. Akram, J.Jang, K.Song, Forward and backward multi-beam scanning controlled by holographic acoustic metasurface, 18, 024008, 2022. Physical Review Applied 

J.Kim, M.Zaman, S.Park, K.Song, Holographic Acoustic Admittance Surface for Acoustic Beamforming. Applied Physics Letters, 115, 193501, 2019 

K. Song et al, Concentric Artificial Impedance Surface for Directional Sound Beamforming, AIP advances 7, 035315 2017 

K. Song ,J.kim, S.Hur, J.Kwak, S.Lee, T.Kim, Directional Reflective Surface Formed via Gradient-Impeding Acoustic Meta-surfaces, Scientific Reports 6, 32300, 2016 

6.   자율주행 자동차용 장거리 초음파 센서  연구 

       •  메타표면 기반 비접촉 초음파 트랜스듀서 

       •  Ultrasonic Emisison Sensor  적용 메타표면 설계 

K. Song et al,  Acoustic meta-surface for efficient impedance matching layer of non-contact ultrasonic transducer, 30, 085011, 2021,   Smart materials and structures. 

K. Song, J.Kwak, JJ.Park, S.Hur, Md.AUZ, J.Kim. Acoustic Beamforming based on Sinusoidally Modulated Admittance Surface, Physical Review Applied, 10, 044025,  2018