Mark Micire (research scientist at the Intelligent Robotics Group at NASA Ames) and Yun Kyung Kim (human-robot iInteraction designer at NASA Ames) were incredibly generous in offering me an opportunity to speak with the AstroBee and Super Ball Bot groups at NASA Ames. We’ve been keeping an eye on Super Ball Bot over at Super-Releaser, particularly because of the way the teams working on it are bringing simulation and iterative prototyping together to solve the open-ended problems involved in designing a robust control system for bots that can configure themselves into nearly infinite shapes.
The talk focused on the opportunities to use compliant materials to replicate organic mechanisms, the ways Super-Releaser solves problems in soft robotics, and the way we integrate multiple disciplines into our research. Afterwards I was able to see the work of the Super Ball Bot team – developing novel compliant actuators in addition to refining the systems that power their current Ball Bot prototypes.
I was also able to see the AstroBee, which was being evaluated on the biggest granite surface plate I’ve ever seen. I got to talk with Yun about her experience as a designer integrating into a team of engineers, which is its own challenge in itself, and the goals of the AstroBee project. It’s going to serve as a platform to develop behaviors for human/machine interaction in 0g, which is a problem I’ve never even considered.
I was hired by SOLS to help out with their Adaptiv project. The idea was to showcase the procedural modeling techniques, materials, and technologies behind their printed insoles with a futuristic robotic shoe. Jordan Dialto, the industrial design lead at SOLS, approached me in my capacity as lead scientist at Super-Releaser to make a prototype soft robot shoe that could change shape and fit in response to the wearer.
The project started out with an external shell modeled by Continuum Fashion. Although the design was elegant, this posed a challenge for introducing the robotic elements and the engineered components that would stitch everything together. Since the external shell was generated in a mesh CAD program, it didn’t fit into SolidWorks’ reference frame. This meant using the mesh as a reference and generating a simplified surface to extrude the soft robot elements and retaining skeleton from. Continue reading →
I’ve been going to CCC for a while. I’ve given some talks (mostly on the lightning talk track) and have generally had a good time. More and more, though, I’ve gotten interested in gatherings that orbit big events like CCC, Maker Faire, and HOPE. Unconferences, Bsides, and nether-conferences like BarCamp are less formal than a traditional conference, and often have the kind of wiggle room for instant breakout sessions and long Q&A.
Long time no see, folks. I’ve got some great news for you. I’ve finally found a method for getting super complicated geometry locked inside of a seamless skin. It’s taken a lot of prototypes to get here, but I think the results are more than worth the effort. There are some wrinkles to iron out (which I’ll get to below) but all in all I think I’m incredibly close to rapid-fire casting working quadrupeds, ready to go in just a few short steps after popping the mold. In other good news, I’ll be dropping some files very soon which should get you your very own working quadruped using any FDM printer. All you need is a Makerbot or similar, a few hours, and some casting materials to have an exact duplicate of my most sophisticated robot to date.
This will be an update on the things I’ve learned molding quadrupeds over the last couple of months and some previews of the new robots I’ll be experimenting with in the next few weeks. To start, I’ve had the chance to run a gaggle of design experiments ranging from small changes to the particular silicone I’ve been casting, to more radical changes to how the whole plionics manufacturing process comes together.
I’ve discovered that molding complex channels of tubing can be extremely difficult, and the CAD equally infuriating. I’m discovering some automatic routing tools in SolidWorks that could streamline the process, but there might be another solution that sidesteps that whole mess entirely. It’s possible to cast around silicone tubing that’s already connecting up all the interior geometry. So, what I’d have to do to get the design working is build the cores with little fastenings for plugging in tubing and make sure all the tubes have enough clearance to get past one another. I’m anticipating the world of reality doesn’t let me off the hook that easily, but it’s a start. Continue reading →
Earlier this week I had the opportunity to show off the soft robots I’ve been developing at the National Robotics Week: Extending Human Reach event held at HUGE labs and facilitated by Honeybee Robotics. I was originally excited at the prospect of seeing the incredibly varied group, the police standing next to bomb sniffing drones, LittleBits showing off tiny circuit construction kits, Honeybee demonstrating the lab tools they designed that are currently roving around on Mars. It was a shame I didn’t have more time away from my booth to check out the tech everyone else brought, but the general crowd was so excited, so eager to chat about robots and what I was presenting, that the event was almost over before I caught my breath. Thankfully Numi was there, helping set up, answering questions, and generally being awesome.
So, now I’ve got a pile of business cards representing science minded folks to email, some new medical applications to push the next prototypes towards, and an urge to show this stuff off to the public more.
Quadrupeds. I’ve been dreaming about quadrupeds. I’ve been hunting for challenges to test my methods and improve the engineering on the whole “print and cast a soft robot” thing (I really need to come up with a name for this… “Borgatronics?”). I started with tentacles because they were easy to design, easy to test, and symmetrical.
They’ve made a lot of progress, but it’s time to turn to other designs. I’ve produced a few prototypes along one main design, and have discovered many things. I’m going to try and explain my logic behind the design and some of the major changes I intend to make in the next version. I’m also going to tell you all the myriad ways I went wrong in this design and the things I’ve done to try and make it right.
This is going to be a pretty dry technical post on the industrial design aspects of the robots I’ve been developing. I promise you entertainment and levity aplenty in the future. For now, we grump about casting flaws, mold design, and process control. Continue reading →
I am now the grinning overlord of a fully functional robotic tentacle. I’m quite pleased. After a few iterations, some hair pulling, and some utterly excellent help from programmer, hacker, and generally awesome person TQ, the Trefoil Tentacle is now waving about in all its eerie undulating glory. You can find a whole set of high res images of it here.
The control scheme is pretty simple: a barebones visual interface in Processing sends signals to an Arduino. From there, it switches the low power signal to high power via a Darlington transistor. The transistor switches each of 3 solenoid valves on and off, providing air to each of the 3 bladders inside of the silicone tentacle. The valves operate on a really slow PWM, their duty cycle determining how much air makes it to each bladder. Since there’s a bleed I can control on the system, I don’t have to worry about pumping air both in and out. I just adjust how much time the valves spend on, and the tentacle does it’s routine. All of the code for the setup is here on Adafruit’s forum. Continue reading →
Last week I headed up to Viridis3d for some more hacking. We got some beautiful results using some vaccuum casting with the trefoil design, parts printed for both the internals and outer shell of the quadruped, and schemes for tempting new mechanisms. All in all it’s been really exciting seeing the progress. Also, I have some updates on controlling the trefoil tentacle with an arduino powered set of air solenoids.
One of the confounding factors in getting this flavor of robot moving predictably has been how difficult it is to control wall thickness and bubble inclusions when casting the final silicone pieces. Like almost every mold, you do the best you can, try to create a nice, sterile, well ordered universe, and hope. Although Dragon Skin has performed really well as a durable, flexible silicone, it has the nasty habit of trapping bubbles in inconvenient spots when curing. Many silicones have a thin, pancake syrup consistency when mixed, but Dragon Skin is much more like honey or molasses, meaning it’s really easy to trap bubbles in the mix while stirring and have them set in place when everything’s curing. A good solution for the problem is pulling them back out with a vacuum chamber. Continue reading →