Amoeba-Like Whole-Skin Locomotion Robots Ooze Right On By

Early prototype of whole-skin locomotion by Dr. Hong inspired by water snake toy.

Back in 2007 and 2008, funding agencies had a pretty hefty interest in robots with amoeba-like locomotion, also known as whole-skin locomotion (WSL), blob 'bots, or Chembots.  NSF awarded $400k to Dr. Dennis Hong of Virginia Tech's RoMeLa Lab and DARPA awarded $3.3M to iRobot to develop such robots.  Now, most people are familiar with iRobot's jamming skin robot announced at IROS 2009 (photos / videos below).  However, I would like to share with you the equally-clever and interesting work of Dr. Hong, including a new whole-skin locomotion robot called ChIMERA: "Chemically Induced Motion Everting Robotic Amoeba" that was unveiled at a recent TEDxNASA event.  Dr. Hong's robots resemble those slippery water-snake toys that are incredibly difficult to grasp, with silicone skin (flexible but rugged exterior) and water or gel inside (soft interior).  Read on to learn more!

Here is a 30-second excerpt of Dr. Dennis Hong's TEDxNASA talk where he explains the RoMeLa Lab's whole-skin locomotion robots.  The whole (18+ minute) talk is embedded at the bottom of this article.  I recommend watching it if you have time -- it's worth every minute. 

Update 2/10/2010: At the request of TEDxNASA, the reduced length video has been removed.  The salient portion of the full-length video (below) begins at 7:27.


Unfortunately, the interesting chemistry involved in ChIMERA's chemical actuation is still in stealth mode (hopefully a paper forthcoming).  However, early work on ChIMERA is clearly documented in a nice Masters thesis by Mark Ingram, along with his feasibility experiments shown in the video embedded below.

I'm particularly fascinated by the robot's fast movements (0.5 m/s) and ability to squeeze through small holes (half its own diameter).  It certainly piques my imagination.

Whole Skin Locomotion Amoeba Robot
Whole Skin Locomotion Amoeba Robot
Whole Skin Locomotion Amoeba Robot


The fact that so much of this early work is based off of slippery water-snake toys, the same ones that I played with as a child and that can be purchased for less than $2 (pictured below-left), certainly speaks to Dr. Hong's ingenuity.  They have certainly made some impressive progress between these new robots and their two-year-old band-driven prototypes (pictured below-right).

Water-Snake Slippery Toy  Whole Skin Locomotion Early Prototype Robot

Naturally, one of the largest challenges is actuating the outer ectoplasm.  So far, we have seen large rotating bands (super-early prototype above), pre-tensioned skin, cable squeezed, and chemical actuation.  The chemical method is compelling because of biological parallels, though I can imagine myriad hurdles in transporting and applying the "fuel."  My favorite method proposed is to use electroactive polymers (below left) as the skin to provide the compressive pressure at the uroid or expansive pressure at the hyaline cap.  It seems they have also proposed using air-driven tubes (below center and right) to provide the necessary pressure.

Whole Skin Locomotion Amoeba Robot    Whole Skin Locomotion Amoeba Robot

Whole Skin Locomotion Amoeba Robot


Of course, it is also prudent to examine iRobot's "Blob 'Bot" that used jamming skin (presented while at IROS 2009) to achieve similar amoeba-like objectives.  

iRobot Jamming Skin Blob Robot iRobot Jamming Skin Blob Robot iRobot Jamming Skin Blob Robot iRobot Jamming Skin Blob Robot iRobot Jamming Skin Blob Robot

The iRobot prototype is the product of $3.3M in DARPA funding from it's Chembot project:

During military operations it can be important to gain covert access to denied or hostile space.  Unmanned platforms such as mechanical robots are of limited effectiveness if the only available points of entry are small openings.

The goal of the Chemical Robots (ChemBots) Program is to create a new class of soft, flexible, mesoscale mobile objects that can identify and maneuver through openings smaller than their dimensions and perform various tasks.

The program seeks to develop a ChemBot that can perform several operations in sequence:

  • Travel a distance
  • Traverse an arbitrary-shaped opening much smaller than the largest characteristic dimension of the robot itself
  • Reconstitute its size, shape, and functionality after traversing the opening;
  • Travel a distance
  • Perform a function or task using an embedded payload.

This program creates a convergence between materials chemistry and robotics through the application of any one of a number of approaches, including gel-solid phase transitions, electro- and magneto-rheological materials, geometric transitions, and reversible chemical and/or particle association and dissociation.

With ChemBots, our warfighters can gain access to denied spaces and perform tasks safely, covertly, and efficiently. 


As promised, here is the entirety of Dr. Dennis Hong's TEDxNASA talk: 




 I hope those reseachers know that someone already created one of these things years ago.


I used to have one when I was a kid.

It was called a WATER WEINER! 


@ Anonymous,

Indeed.  They are also known as water snakes.  As I said, they can be had for sub-$2 on Amazon.

—Travis Deyle

Someone has already found a way to have fish power the little magical tubes : 


I could see that second blob thing taking over the world one day and everyone looking back on it like wow that's how it all started out then it learned too much and destroyed it's creator.

..Just saying 


Very informative post! There is a lot of information here that can help any business get started with a successful social networking campaign! Thank you for sharing information. I am impressed with what you have written in this article.

msp | slope | kahoot


We are tied directly into the sate’s renewal database which allows us to process your request almost instantly. <a href="">buy instagram likes fast</a>


—osama nawaz

Post new comment

The content of this field is kept private and will not be shown publicly.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Allowed HTML tags: <a> <em> <strong> <cite> <code> <ul> <ol> <li> <dl> <dt> <dd> <p>
  • HTML tags will be transformed to conform to HTML standards.

More information about formatting options