After testing the Flat-Pack Camera Arm I built, I was pretty happy with the results. Happy, except for one detail: the joint at the base of the arm would creep down over time. This wasn’t a problem while taking shots of projects at the bench, given how often I’d have to reposition it anywhere. The big breakdown was trying to capture time lapses. The creep was just too noticeable, and it would never stay in place long enough to keep the action of a day’s hacking in frame.
So, I set out to make some locking plates for the arm, and I think people could find some interesting uses for the process I came up with. The broad strokes of the method are that you design the part you’d like at the end in CAD, design a floor under your part with walls around it (I call this a bathtub), print the bathtub mold you designed, cast the mold using 2-part silicone (making sure it’s nice and level), and cast your final material into that mold. Once you’ve got the knack of replicating parts using 1-part molds, you can get fancier: adding vent holes for letting air escape or labels for your parts or building multiple parts for your molds for even more precise geometry.
Below you can find more information on the whole project:
I’ve been wanting an extra set of hands to hold a camera while I document projects for a long time. Kari and I are writing a book for MAKE all about soft robotics, and I figure there’s probably not going to be a better time to have a serious documentation setup than when someone’s paying me to do a good job at it. Since NYC Resistor just got a ShopBot and I’ve been meaning to get back into plywood fab for years, it seemed like a pretty auspicious syzygy. If you’d like to replicate this design for yourself, you can find the source files and project notes here. You can also see my photos from the cutting and assembly of the project here. Continue reading →
The Glaucus is a soft robotic quadruped composed of a single seamless silicone part. It has a complex network of interior channels, created via a lost wax process, that turn into actuators when pressurized with air. It’s able to walk with a diagonal gait, similar to a gecko or Glaucus Atlanticus sea slug, using only two input channels.
The Glaucus was created to demonstrate a method for fabricating soft robots of nearly any geometry with arbitrary interior structures. It’s been my goal, since beginning my research into soft robotics, to simplify the process of prototyping and refining designs. Often the barrier between an interesting bench prototype and practical application is how it scales into production. If methods for experimenting with the core concepts, evaluating them in a context that represents their final manufactured state, and refining them for mass production don’t exist, the idea is very likely to languish on the bench. Continue reading →
This project involves AC power, high amperage, and high temperatures. Although this project is simple in principle replicating it on your own offers a lot of opportunities to hurt yourself. Proceed with caution.
Microwaves are treasure troves of useful electronic components. They’ve usually got some nice microswitches, a big transformer, a magnetron, and some smaller transformers and rectifiers to drive the display. I found a decent sized microwave hanging out on the street and transformed it into a shop tool I’d been wanting for a while – a spot welder.
Why Spot Welders are Useful
Spot welders are handy to have around the shop. They can tack together wire for quick brazing, and permanently weld sheet metal for durable enclosures. If you want a thorough guide on what you can do with a spot welder, Dan Gelbart has all the answers. I’ve been looking to up my prototyping game and have more freedom to build custom components when off the shelf parts won’t suit. Unfortunately my workshop is in Brooklyn and space is at a premium. I spent a lot of time fabricating structures out of steel wire in school and have found that it’s a good replacement for bent sheet metal and structural framing if you play your cards right. Wire is easy to store in a small shop, doesn’t take much equipment to manipulate, and can hold good tolerances in various dimensions as its behavior is very predictable. You can still find the manual I follow for a lot of my techniques on Amazon. Continue reading →
I’m fond of giving people gifts, but often shy away from just giving people stuff. There’s a complex dance of figuring out if it’ll be useful, if the quality’s any good, if they’ve already got one around, that muddies the water. I prefer to make something that doesn’t take up much space and has the chance of getting used up rather than living out the rest of its existence in storage. I’ve found that infusions work pretty perfectly for this job.
I’ve gone through a lot of recipes and variations over the years (they’ll likely show up on this blog eventually) but I was especially fond of this batch made in 2013. I made 5 infusions as christmas gifts to send to friends and family. The mixes were black pepper vodka, pumpkin vodka, lady grey tea gin, raw honey vodka, and red pepper tequila. Continue reading →
Do you like 3D printing, mold making, industrial design, jewelry, and RGB LED’s? You’re in luck, then. I just finished this tutorial for Adafruit and think it’s well worth a look.
In this project, I attempted to make an Arduino powered device that was easy to use, easy to make, and self contained. Every 3d printed component can be done in a single build without support material. The ring has a battery, switch, and USB port. Once it’s together, all you need to charge or reprogram it is a USB Micro cable.
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 →
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 →