It’s the podcast so nice we recorded it twice! Despite some technical difficulties (note to self: press the record button significantly before recording the outro), Elliot and Dan were able to soldier through our rundown of the week’s top hacks.
We kicked things off with a roundup of virtual keyboards for the alternate reality crowd, which begged the question of why you’d even need such a thing. We also looked at a couple of cool demoscene-adjacent projects, such as the ultimate in oscilloscope music and a hybrid knob/jack for eurorack synth modules.
We dialed the Wayback Machine into antiquity to take a look at Clickspring’s take on the origins of precision machining; spoiler alert — you can make gas-tight concentric brass tubing using a bow-driven lathe. There’s a squishy pneumatic robot gripper, an MQTT-enabled random number generator, a feline-friendly digital stethoscope, and a typewriter that’ll make you Dymo label maker jealous.
We’ll also mourn the demise of electronics magazines and ponder how your favorite website fills that gap, and learn why it’s really hard to keep open-source software lean and clean. Short answer: because it’s made by people.
One might be tempted to think that re-creating a film robot from the 1950s would be easy given all the tools and technology available to the modern hobbyist, but as [Mike Ogrinz]’s quest to re-create Robby the Robot shows us, there is a lot moving around inside that domed head, and requires careful and clever work.
The “dome gyros” are just one of the complex assemblies, improved over the original design with the addition of things like bearings.
Just as one example, topping Robby’s head is a mechanical assembly known as the dome gyros. It looks simple, but as the video (embedded below) shows, re-creating it involves a load of moving parts and looks like a fantastic amount of work has gone into it. At least bearings are inexpensive and common nowadays, and not having to meet film deadlines also means one can afford to design things in a way that allows for easier disassembly and maintenance.
Robby the Robot first appeared in the 1956 film Forbidden Planet and went on to appear in other movies and television programs. Robby went up for auction in 2017 and luckily [Mike] was able to take tons of reference photos. Combined with other enthusiasts’ efforts, his replica is shaping up nicely.
We’ve seen [Mike]’s work before when he shared his radioactive Night Blossoms which will glow for decades to come. His work on Robby looks amazing, and we can’t wait to see how it progresses.
How far can you stretch a measuring tape before it buckles? The answer probably depends more on the tape than the user, but it does show how sturdy the coiled spring steel rulers can be. [Gengzhi He et. al.] may have been playing that game in the lab at UC San Diego when they hit upon the idea for a new kind of low-cost robotic gripper.
Four motors, four strips of measuring tape (doubled up)– one robot hand.
With the lovely backronym “GRIP-tape” — standing for Grasping and Rolling in Plane — you get a sense for what this effector can do. Its two “fingers” are each made of loops of doubled-up measuring tape bound together with what looks suspiciously like duck tape. With four motors total, the fingers can be lengthened or shortened by spooling the tape, allowing a reaching motion, pivot closer or further apart for grasping, and move-in-place like conveyor belts, rotating the object in their grasp.
The combination means it can reach out, grab a light bulb, and screw it into a socket. Or open and decant a jar of spices. Another video shows the gripper reaching out to pick a lemon, and gently twist it off the tree. It’s quite a performance for a device with such modest components.
At the moment, the gripper is controlled via remote; the researchers plan on adding sensors and AI autonomous control. Read all the details in the preprint, or check below the fold to watch the robot in action.
[Charmed Labs] are responsible for bringing numerous open-source hardware products to fruition over the years, and their latest device is an adorably small robotic camera platform called Goby, currently crowdfunding for its initial release. Goby has a few really clever design features and delivers a capable (and hackable) platform for under 100 USD.
Goby embraces its small size, delivering what its creators dub “tinypresence” — or the feeling of being there, but on a very small scale. Cardboard courses, LEGO arenas, or even tabletop gaming scenery hits different when experienced from a first-person perspective. Goby is entirely reprogrammable with nothing more than a USB cable and the Arduino IDE, while costing less than most Arduino starter kits.
Recharging happens by driving over the charger, then pivoting down so the connectors (the little blunt vampire fangs under and to each side of the camera) come into contact with the charger.
One of the physical features we really like is the tail-like articulated caster at the rear. Flexing this pivots Goby up or down (and can even flip Goby completely over), allowing one to pan and tilt the view without needing to mount the camera on a gimbal. It also comes into play for recharging; Goby simply moves over the disc-shaped charger and pivots down to make contact.
At Goby‘s heart is an ESP32-S3 and OmniVision OV2640 camera sensor streaming a live video feed (and driving controls) with WebRTC. Fitting the WebRTC stack onto an ESP32 wasn’t easy, but opens up possibilities beyond just media streaming.
Goby is set up to make launching an encrypted connection as easy as sharing a URL or scanning a QR code. The link is negotiated between bot and client with the initial help of an external server, and once a peer-to-peer connection is established, the server’s job is done and it is out of the picture. [Charmed Labs]’s code for this functionality — named BitBang — is in beta and destined for an open release as well. While BitBang is being used here to make it effortless to access Goby remotely, it’s more broadly intended to make web access for any ESP32-based device easier to implement.
As far as tiny remote camera platforms go, it might not be as small as rebuilding a Hot Wheels car into a micro RC platform, but it’s definitely more accessible and probably cheaper, to boot. Check it out at the Kickstarter (see the first link in this post) and watch it in action in the video, embedded just below the page break.
Most robots depend on controlled environments, because the real world is hard to get around in. The smaller the robot, the bigger this problem because little wheels (or legs) can take only little steps. One way around that is MIT’s latest one-legged hopping robot, which sports a set of four insect-like wings on its top end and can quickly pogo-hop its way across different terrain with ease.
The four wings provide lift, and steer the robot so that its single leg lands precisely.
The wings aren’t for flying in the usual sense. They provide lift, but also help the tiny device steer itself so that its hops land precisely. Earlier incarnations of one-legged hopping robots (like this one) accomplished this with propellers and electric motors, but traditional motors are a non-starter on a device that weighs less than a paperclip.
Right now, this little winged hopper is not completely self-contained (power and control systems are off-board) but running it as a tethered unit allows researchers to test and evaluate different, minimalistic ways for a machine to move around efficiently. And efficiency is the whole goal of going in this direction.
Certainly tiny flying drones already exist and get about in the real world just fine. But if one wants to shed mass, ditch conventional motors, and reduce cost and power consumption, this tiny winged hopping machine is one way to do it. And it can even carry payloads! The payloads are tiny, of course, but being able to haul around ten times one’s own weight and still function reliably is an impressive feat.
You can watch it in action in the video embedded just below the page break. Once you’ve watched that, we’d like to remind you that novel locomotion isn’t just the domain of hopping robots. Tiny robots with explosive joints is just as wild as it sounds.
If you want to get started in microfluidic robotics, [soiboi soft’s] salamander is probably too complex for a first project. But it is impressive, and we bet you’ll learn something about making this kind of robot in the video below.
The pneumatic muscles are very impressive. They have eight possible positions using three sources of pressure. This seems like one of those things that would have been nearly impossible to fabricate in a home lab a few decades ago and now seems almost trivial. Well, maybe trivial isn’t the right word, but you know what we mean.
The soft robots use layers of microfluidic channels that can be made with a 3D printer. Watching these squishy muscles move in an organic way is fascinating. For right now, the little salamander-like ‘bot has a leash of tubes, but [soiboi] plans to make a self-contained version at some point.
[JesseDarr] recently wrote in to tell us about their dynamic Arm for Robitc Mischief (dARM), a mostly 3D printed six degrees of freedom (6DOF) robotic arm that’s designed to be stronger and more capable than what we’ve seen so far from the DIY community.
The secret? Rather than using servos, dARM uses brushless DC (BLDC) motors paired with ODrive S1 controllers. He credits [James Bruton] and [Skyentific] (two names which regular Hackaday readers are likely familiar with) for introducing him to not only the ODrive controllers, but the robotics applications for BLDCs in the first place.
dARM uses eight ODrive controllers on a CAN bus, which ultimately connect up to a Raspberry Pi 4B with a RS485 CAN Hat. The controllers are connected to each other in a daisy chain using basic twisted pair wire, which simplifies the construction and maintenance of the modular arm.
As for the motors themselves, the arm uses three different types depending on where they are located, with three Eaglepower 8308 units for primary actuators, a pair of GB36-2 motors in the forearm, and finally a GM5208-24 for the gripper. Together, [JesseDarr] says the motors and gearboxes are strong enough to lift a 5 pound (2.2 kilogram) payload when extended in a horizontal position.
The project’s documentation includes assembly instructions for the printed parts, a complete Bill of Materials, and guidance on how to get the software environment setup on the Raspberry Pi. It’s not exactly a step-by-step manual, but it looks like there’s more than enough information here for anyone who’s serious about building a dARM for themselves.
