BOARD - 눈으로 들어가는 로봇 (Swimming Robotic Micro-Scallop)

Designing robots on the micro or nano scale (like, small enough to fit inside your body) is all about simplicity. There just isn’t room for complex motors or actuation systems. There’s barely room for any electronics whatsoever, not to mention batteries, which is why robots that can swim inside your bloodstream or zip around your eyeballs are often driven by magnetic fields. However, magnetic fields drag around anything and everything that happens to be magnetic, so in general, they’re best for controlling just one single microrobot robot at a time. Ideally, you’d want robots that can swim all by themselves, and a robotic micro-scallop, announced today in Nature Communications, could be the answer.

When we’re thinking about robotic microswimmers motion, the place to start is with understanding how fluids (specifically, biological fluids) work at very small scales. Blood doesn’t behave like water does, in that blood is what’s called a non-Newtonian fluid. All that this means is that blood behaves differently (it changes viscosity, becoming thicker or thinner) depending on how much force you’re exerting on it. The classic example of a non-Newtonian fluid is oobleck, which you can make yourself by mixing one part water with two parts corn starch. Oobleck acts like a liquid until you exert a bunch of force on it (say, by rapidly trying to push your hand into it), at which point its viscosity increases to the point where it’s nearly solid.

These non-Newtonian fluids represent most of the liquid stuff that you have going on in your body (blood, joint fluid, eyeball goo, etc), which, while it sounds like it would be more complicated to swim through, is actually an opportunity for robots. Here’s why:

At very small scales, robotic actuators tend to be simplistic and reciprocal. That is, they move back and forth, as opposed to around and around, like you’d see with a traditional motor. In water (or another Newtonian fluid), it’s hard to make a simple swimming robot out of reciprocal motions, because the back and forth motion exerts the same amount of force in both directions, and the robot just moves forward a little, and backward a little, over and over. Biological microorganisms generally do not use reciprocal motions to get around in fluids for this exact reason, instead relying on nonreciprocal motions of flagella and cilia.

However, if we’re dealing with a non-Newtonian fluid, this rule (it’s actually a theorem called the Scallop theorem) doesn’t apply anymore, meaning that it should be possible to use reciprocal movements to get around. A team of researchers led by Prof. Peer Fischer at the Max Planck Institute for Intelligent Systems, in Germany, have figured out how, and appropriately enough, it’s a microscopic robot that’s based on the scallop.

As we discussed above, these robots are true swimmers. This particular version is powered by an external magnetic field, but it’s just providing energy input, not dragging the robot around directly as other microbots do. And there are plenty of kinds of micro-scale reciprocal actuators that could be used, like piezoelectrics, bimetal strips, shape memory alloys, or heat or light-actuated polymers. There’s lots of design optimizations that can be made as well, like making the micro-scallop more streamlined or “optimizing its surface morphology,” whatever that means.

The researchers say that the micro-scallop is more of a “general scheme” for micro-robots rather than a specific micro-robot that’s intended to do anything in particular. It’ll be interesting to see how this design evolves, hopefully to something that you can inject into yourself to fix everything that could ever be wrong with you. Ever.

[ Nature Communications ]

제목	조회	등록일
종이에 빛을 가하자 스스로 '변신'…종이 로봇	6462	2015-12-02
성적 기대치 높은 부모...자녀들의 실제 성적은?	5953	2015-12-02
바다표범 수염은 레이더...수염으로 먹이 찾는다	6570	2015-11-04
영화 ‘백 투 더 퓨처’가 그린 '미래'와 '현실'	7448	2015-10-25
물 절약 참신한 아이디어	30554	2015-10-18
미래부·KISTI, ‘미래유망기술 11선’ 선정	10237	2015-10-17
Five Recent Advances in Life Science Research [5]	13994	2015-09-30
명왕성 비밀의 문이 열린다.	7073	2015-09-14
일상 속 진동을 잡아라 [3]	8632	2015-09-14
마블 히어로 ‘앤트맨’의 과학, 어디까지 사실일까?	10841	2015-09-05
A Universe in a Nutshell: The Physics of Everything, with Michio Kaku	83412	2015-09-05
학부생의 연구 성과, 석·박사 수준까지 올라	8308	2015-08-26
폭스바겐이 만든 스마트 유모차	7988	2015-08-25
블록 조립하듯 ‘DNA’를 스스로 뗐다 붙였다...‘나노 로봇’ 개발	8354	2015-08-18
Intelligent Self-Cleaning Rear View Camera	11084	2015-08-12
'유창한 영어'에 대한 한국인의 착각	6553	2015-08-10
국내 연구진, 수면 위 뛰는 ‘소금쟁이 로봇’ 개발 성공 [4]	8389	2015-08-05
아이언맨? 탄소나노튜브맨! [1]	14841	2015-05-26
테슬라모터스 CEO 일론 머스크 (Elon Musk) [2]	10682	2015-05-23
미군, ‘투명 망토’ 도입…투명인간 머지 않았다?	8475	2015-05-12

눈으로 들어가는 로봇 (Swimming Robotic Micro-Scallop)

Robotic Micro-Scallops Can Swim Through Your Eyeballs