Nitin Kumar

Capillary interactions drive the self-organization of bacterial colonies - Nature Physics Bacteria tend to live in thin layers of water on surfaces. Now the capillary forces in these layers are shown to help organize the bacteria into dense packs.

Dreaming of a swimming pool? Bacteria are surrounded by water! Water capillary forces organize bacterial colonies into gas, nematic streams, or droplet states. New paper @natphys.nature.com led by Matt Black and Chenyi Fei, with Ned Wingreen and Josh Shaevitz!

www.nature.com/articles/s41...

Preprint alert 📣! We provide an experimental protocol to align clay nanotubes over the entire dried deposit in spite of huge size-polydispersity. Experiments by my postdoc Arun Dadwal. Supported by @iitbombay.bsky.social

arxiv.org/html/2505.03...

(6/6) We quantify RT motion in terms of tumbling rate and show its systematic variation as a function of various experimental parameters. Our theoretical model reproduces experiments and elucidates the physics of underlying phenomena. More details in the preprint. Thanks😃

(5/6) Key to this RT motion is our robot's rolling-without-slipping, inertia-less active motion, which is expected in microswimmers. To confirm this, we used a slippery surface coated with coconut oil and found that the sudden tumble events smoothened out and vanished completely.

(4/6) When robots are programmed to execute overdamped active Brownian (AB) motion, voila, RT motion emerges, featuring abrupt tumbling events and exponential run-time distributions.

(3/6) Inspired by that, we create a robotic organism: two self-propelled robots connected by a rigid rod. Here, robots mimic flagella, and the rod acts as the organism's body. The rod rotates freely in a plane, with its ends pivoted at mirror-symmetric points on each robot.

a drawing of a blue bacteria with purple circles around it and the words addgene below it ALT: a drawing of a blue bacteria with purple circles around it and the words addgene below it

(2/6) Microswimmers like bacteria and algae use active units, called cilia or flagella, to attain motility in a low Re environment. Flagella undergo a series of synchronous and asynchronous beating cycles to produce straight trajectories (runs) and sudden random turns (tumbles).

(1/6) 📢Excited to share our latest work in collaboration with @harshIITMandi's group at IIT Mandi on an artificial robotic system 🤖, in experiment and theory, mimicking run-and-tumble (RT) motion seen in microorganisms 🦠. 🧵⏬
arxiv.org/abs/2502.01257

YouTube video by RnD @ IITB Self-Propelling Robot Reveal the Physics Behind Animal Homing

A short video highlighting our research on the physics of homing behavior in animals, recently published in PRX Life journal.

youtu.be/Pr0UdzK7kyg?...

I do the same and I have also seen similar ones. And yes my primary objective is also that they go through the course content and at least learn something in the process 😃

As part of the institute's outreach program #TechConnect #TechFest2024, our group showcased a hands-on experience with our active robots, demonstrating how we engineer them to uncover the physics of #LivingMatter and #ActiveMatter @IITBombay

Congratulations Shila..👏🏼

Add me also. Thank you 😊

Add me as well. Thanks :)