Big Hero 6 and the Current State of the Art in Soft Inflatable Robots

Big Hero 6 inflatable robot

This weekend a new Disney movie came out in theaters: Big Hero 6. I'm super excited for this movie, and I'm sure it will be awesome! Even better, the main supporting character is a big, soft inflatable robot named Baymax. As long-time readers of Hizook will undoubtedly know, I'm a huge proponent of inflatable robots -- they have challenges, but they're tough to beat in terms of cost and power-to-weight ratio! And while the movie was inspired by some early work from CMU, I think this is an ideal opportunity to look at the cutting edge in soft, inflatable robotics -- which to my knowledge is dominated by an Otherlab spinout: Pneubotics.  Read on for details, lots of pictures and videos, and a bonus: Watch my wife take a sucker punch to the gut from an inflatable robot!  :-P


Big Hero 6: Baymax the Inflatable Robot


You can find plenty of trailers online (here and here), but realistically you should just go see the movie! To put it in perspective... Disney built a 55,000 CPU core rendering cluster with 400 TBytes of memory and 4PBytes of storage. The cluster, which would rank in the top-75 supercomputer list, allowed animators to render an average of 1.1 million render-hours per day during production. They also developed a new rendering engine named "Hyperion" that does full-on ray tracing while exploiting locality in the system (basically, bin and sort rays before doing ray tracing to avoid expensive texture lookups; PDF paper: "Sorted Deferred Shading for Production Path Tracing").

Big Hero 6's Baymax, a big inflatable robot


Anyway, back to robots. :)  The co-lead character in the movie, as seen from the capture above, is an inflatable robot named Baymax. To quote Wikipedia:

Scott Adsit as Baymax, an inflatable robot built by Tadashi to serve as a healthcare companion. Hall said "Baymax views the world from one perspective—he just wants to help people, he sees Hiro as his patient." Producer Roy Conli said "The fact that his character is a robot limits how you can emote, but Scott was hilarious. He took those boundaries and was able to shape the language in a way that makes you feel Baymax’s emotion and sense of humor. Scott was able to relay just how much Baymax cares."

Big Hero 6's Baymax, a big inflatable robot


To quote my brother, "I can't believe you went to see Interstellar first. BH6 is about a guy in some sort of advanced college doing research on helper robots... It is pretty much about you; I think you could probably sue them."  I wouldn't go that far... but I was planning to see BH6 first -- I had free tickets to a Google private showing, but I got consumed with some urgent deliverables and missed out. Next weekend!

Baymax even uses a projector to display his intentions; just like we've written about previously!

Big Hero 6's Baymax, a big inflatable robot


According to press reports, Baymax was inspired by Siddharth Sanana's work with Prof. Chris Atkeson at CMU. I have no reason to disbelieve the reports... and in fact, I covered this work in my previous article too. But I was a bit disappointed, because: (a) I believe Pneubotics' work is at least an order of magnitude more advanced, yet they've received virtually no media attention; and (b) I believe Otherlab's work predated that of CMU's; Siddharth even interned at Otherlab prior to completing his thesis.  Oh well.... it's a movie about inflatable robots!!

Inflatable robot arm from CMU  Inflatable robot arm from CMU

Cutting Edge Inflatable Robots from Pneubotics


I think Pneubotics (an Otherlab spinout) is probably the leader in this space. Unlike the early CMU cable-driven robots that inspired Baymax, Pneubotics' robots use pneumatic, inflatable actuators to remain "soft" throughout. To quote:

Pneubotics’ first product is an industrial robot arm that has no motors, bearings, shafts, or other rigid parts. It’s a shell of vinyl lined with veins and soft pressure vessels that hold air, water, or hydraulic fluid to work like muscles.


I had an opportunity to visit Otherlab back in April 2014 (that's me, below right), where I got some hands-on experience with several inflatable robot arms, including the arm that I wrote about previously.

Soft, inflatable robot arm from Pneubotics (an Otherlab company)  Travis Deyle shaking hands with an inflatable robot at Otherlab


Actually, my wife came along too.  She was playing around, manually controlling the red robot arm... when she got sucker-punched to the gut by the inflatable robot. It was hilarious! Check out the video.

Wife sucker punched by inflatable robot arm  Wife sucker punched by inflatable robot arm  Wife sucker punched by inflatable robot arm


Otherlab has gone so far as to make dual-armed humanoids (called Blobots) that duked it out in robot boxing matches at various Maker Faire events.  They basically made real-life inflatable Rock-Em Sock-Em robots!

Inflatable soft robot for boxing (aka rock 'em sock 'em)  Inflatable soft robot for boxing (aka rock 'em sock 'em)  Inflatable soft robot for boxing (aka rock 'em sock 'em)


Because of the power-to-weight ratio, these arms can be made amazingly low-mass while still being fast and reactive. Check out this video of an arm being whipped around at high-speed (just think of the "wacky waving arm-flailing tube guys"):

Soft, inflatable robot arm from Pneubotics (an Otherlab company)


In fact, this same inflatable technology is being used elsewhere at Otherlab to explore prosthetics (images below left and center). Similar inflatable prosthetics are being explored by researchers at Harvard (image below right), where they recently obtained $2.9M in DARPA funding.

Otherlab's inflatable exoskeleton  Otherlab's inflatable exoskeleton   Inflatable exoskeleton from Harvard



iRobot's Inflatable Robot Arm and Hexapod:


Otherlab isn't the only game in town. A while back, IEEE Spectrum covered iRobot's inflatable robot arm and inflatable hexapod. This was part of a DARPA program (the same that funded some of the Otherlab work), but I haven't seen or heard about any new iRobot inflatable developments in the last few years.

Inflatable robot arm from iRobot  Inflatable robot walker (hexapod) from iRobot  



Inflatable Umanned Aerial Vehicles


But I have seen some interesting developments out of China, namely inflatable UAV Drones:

Inflatable UAV drone  Inflatable UAV drone  Inflatable UAV drone


This is a really interesting idea. You can reduce the overall system weight (or even add positive buoyancy via different gas mixtures) while still getting reasonable mechanical stability.  I like it!





Anyway, that's about all the inflatable robotics news updates I've seen since 2011. I remain supremely optimistic about the technology, though I get the impression that we're still waiting for the "killer application" (hopefully not literally).

One final remark: If you happen to know anyone at Disney engineering, marketing, or licensing (related to BH6 or not)... please have them contact me. I have a fantastic idea for how to inexpensively build an inflatable Baymax (toy or life size) -- one that actually works! It's obviously too late for BH6 merchandising this season, but it would be supremely relevant if they do a sequel!