researchers from the USC viterbi school of engineering have developed new 3D printed acoustic metamaterials that are able to be remotely switched on and off using a magnetic field. the materials consist of precisely designed, geometric structures that exhibit abnormal properties allowing them to control acoustic or optical waves.


the materials can be controlled using a magnetic field, switching them between active control and passive states. metamaterials can be used to manipulate wave phenomena such as radar, sound and light and have been used to develop technology such as cloaking devices and improved communication systems. however, due to their fixed geometry their unique abilities are also fixed.

3D printed acoustic metamaterials can be switched on and off to block out sound

all images courtesy of viterbischool



the USC viterbi school of engineering team’s metamaterials are able to control environmental sounds and structural vibrations, which have similar waveforms. by 3-D printing a deformable material containing iron particles in a lattice structure, their metamaterials can be compressed using a magnetic field. unlike a physical contact force like a metal plate, the magnetic field compresses the material and so it is not constrained. therefore, when an acoustic or mechanical wave contacts the material, it perturbs it.


the abstract reads: the mechanism relies on the abnormal properties of their metamaterials – negative modulus and negative density. in everyday materials, these are both positive…typically, when you push on an object, it pushes back against you. in contrast, objects with a negative modulus attract you, pulling you towards them as you push. objects exhibiting a negative density work in a similarly contradictory way. when you push these objects away from you, they instead move toward you. one negative property, either negative modulus or negative density, can work independently to block noise and stop vibrations within certain frequency regimes. however, when working together, the noise or vibration can pass through again. the team is able to maintain versatile control over the metamaterial, switching among double-positive (sound passing), single-negative (sound blocking), and double-negative (sound passing) just by switching the magnetic field.’


there are indeed a number of possible applications for smartly controlling acoustics and vibrations,’ ph.d. student kun-hao yu and part of the research group said.traditional engineering materials may only shield from acoustics and vibrations, but few of them can switch between on and off.’

    have something to add? share your thoughts in our comments section below.

    comments policy
    LOG IN
    designboom's comment policy guidelines
    generally speaking, if we publish something, it's because we're genuinely interested in the subject. we hope you'll share this interest and if you know even more about it, please share! our goal in the discussion threads is to have good conversation and we prefer constructive opinions. we and our readers have fun with entertaining ones. designboom welcomes alerts about typos, incorrect names, and the like.
    the correction is at the discretion of the post editor and may not happen immediately.

    what if you disagree with what we or another commenter has to say?
    let's hear it! but please understand that offensive, inappropriate, or just plain annoying comments may be deleted or shortened.

    - please do not make racist, sexist, anti-semitic, homophobic or otherwise offensive comments.
    - please don't personally insult the writers or your fellow commenters.
    - please avoid using offensive words, replacing a few letters with asterisks is not a valid workaround.
    - please don't include your website or e-mail address in your comments for the purpose of self-promotion.
    - please respect jury verdicts and do not discuss offensively on the competition results
    (there is only one fist prize, and designboom usually asks renown professionals to help us to promote talent.
    in addition to the awarded designs, we do feel that almost all deserve our attention, that is why we publish
    the best 100-200 entries too.)

    a link is allowed in comments as long as they add value in the form of information, images, humor, etc. (links to the front page of your personal blog or website are not okay). unwelcome links (to commercial products or services of others, offensive material etc. ) will be redacted. and, ... yes, spam gets banned. no, we do not post fake comments.


    a diverse digital database that acts as a valuable guide in gaining insight and information about a product directly from the manufacturer, and serves as a rich reference point in developing a project or scheme.

    technology news