Getting Hackers Excited About Cable Robots

July 18, 2019 by 22 Comments

Ever since he looked into them as a way to water and care for his plants, [Tom] has been fascinated with cable robots. These high-flying gadgets can move in three dimensions over huge areas, provided you’ve got the ability to string up the aforementioned cables. But despite their flexibility, there hasn’t been a whole lot of hobbyist level development with these unique systems.

With his entry into the 2019 Hackaday Prize, [Tom] is hoping to change that. He’s learned a lot by building his own cable robots, and now wants to take it to the next level. Ideally with collaboration from the community, if he can find other hackers looking to outfit their homes or workshops with their own miniature sky cranes.

So what can you do with a cable robot? In the video after the break, [Tom] shows one of his creations dutifully transporting beer cans across the room and stacking them into a pyramid. Admittedly this isn’t a particularly useful capability (unless you run a bar, perhaps), but it does show the speed and dexterity of the system even when crossing large distances. If you’ve ever wanted to play the home edition of “Automate the Freight”, this one’s for you.

The system uses a trio of 36 volt stepper motors powered by a homebrew SLA7078 driver that [Tom] designed himself. Each stepper turns a geared-down spindle to which a strong cable is attached. With some clever routing around the workspace, careful orchestration of these small winches can be used to move the point where all the cables meet in 3D space. All that’s left is mounting your gadget of choice to this central point, and away you go.

We’ve seen the concept used commercially, but as far as hobbyist projects go, the most activity we’ve seen in this space would have to be the various room sized 3D printers that have popped up over the years. It would be interesting to see what kind of interesting projects the community could come up with if they had something with a little more muscle.

Continue reading “Getting Hackers Excited About Cable Robots” →

Hacking Shelters And Swimming Pools

July 18, 2019 by 44 Comments

How would you survive in a war-torn country, where bombs could potentially fall from the sky with only very short notice? And what if the bomb in question were The Bomb — a nuclear weapon? This concern is thankfully distant for most of us, but it wasn’t always so. Only 75 years ago, bombs were raining down on England, and until much more recently the threat of global thermonuclear war was encouraging school kids to “duck and cover”. How do you protect people in these situations?

The answers, naturally, depend on the conditions at hand. In Britain before the war, money was scarce and many houses didn’t have basements or yards that were large enough to build a family-sized bomb shelter in, and they had to improvise. In Cold War America, building bomb shelters ended up as a boon for the swimming pool construction industry. In both cases, bomb shelters proved to be a test of engineering ingenuity and DIY gumption, attempting to save lives in the face of difficult-to-quantify danger from above.

Continue reading “Hacking Shelters And Swimming Pools” →

Project Egress: The Hinges

July 18, 2019 by 34 Comments

A door’s hinges are arguably its most important pieces. After all, a door without hinges is just, well, a wall. Or a bulkhead, if we’re talking about a hingeless hatch on a spacecraft.

And so the assignment for creating hinges for Progress Egress, the celebration of the 50th anniversary of the Apollo 11 landing by creating a replica of the command module hatch, went to [Jimmy DiResta]. The hinges were complex linkages that were designed to not only handle the 225 pound (102 kg) hatch on the launch pad, but to allow extended extravehicular activity (EVA) while en route to the Moon. [Jimmy], a multimedia maker, is just as likely to turn metal as he is to work in wood, and his hinges are a study of 1960s aerospace engineering rendered in ipe, and extremely hard and dense tropical hardwood, and brass.

[Jimmy]’s build started with a full-size 3D-printed model of the hinge, a move that paid off as the prints acted both as templates for machining the wood components and as test jigs to make sure everything would articulate properly. Sheet brass was bent and soldered into the hinge brackets, while brass rod stock was turned on the lathe to simulate the hydraulic cylinder hinge stays of the original. The dark ipe and the brass work really well together, and should go nicely with [Fran Blanche]’s walnut and brass latch on the assembled hatch.

With [Adam Savage]’s final assembly of all the parts scheduled for Thursday the 18th, we’re down to the wire on this celebration of both Apollo and the maker movement that was at least in part born from it.

Note: the assembly started at 11:00 Eastern time, and there’s a live stream at https://airandspace.si.edu/events/project-egress-build.

Continue reading “Project Egress: The Hinges” →

Blacksmithing For The Uninitiated: Curves And Rings

July 18, 2019 by 9 Comments

You know the funny looking side of the anvil? That’s where the best curves come from. It’s called the anvil horn and is the blacksmith’s friend when bending steel and shaping it into curves.

The principle of bending a piece of steel stock is very easy to understand. Heat it up to temperature, and hammer it over a curved profile to the intended shape. A gentler touch is required than when you are shaping metal. That’s because the intent is to bend the metal rather than deform. Let’s take a look!

Continue reading “Blacksmithing For The Uninitiated: Curves And Rings” →

Torturing An Instrumented Dive Watch, For Science

July 18, 2019 by 24 Comments

The Internet is a wild and wooly place where people can spout off about anything with impunity. If you sound like you know what you’re talking about and throw around a few bits of the appropriate jargon, chances are good that somebody out there will believe whatever you’re selling.

Case in point: those that purport that watches rated for 300-meter dives will leak if you wiggle them around too much in the shower. Seems preposterous, but rather than just dismiss the claim, [Kristopher Marciniak] chose to disprove it with a tiny wireless pressure sensor stuffed into a dive watch case. The idea occurred to him when his gaze fell across an ESP-01 module next to a watch on his bench. Figuring the two needed to get together, he ordered a BMP280 pressure sensor board, tiny enough itself to fit anywhere. Teamed up with a small LiPo pack, everything was stuffed into an Invicta dive watch case. A little code was added to log the temperature and pressure and transmit the results over WiFi, and [Kristopher] was off to torture test his setup.

The first interesting result is how exquisitely sensitive the sensor is, and how much a small change in temperature can affect the pressure inside the case. The watch took a simulated dive to 70 meters in a pressure vessel, which only increased the internal pressure marginally, and took a skin-flaying shower with a 2300-PSI (16 MPa) pressure washer, also with minimal impact. The video below shows the results, but the take-home message is that a dive watch that leaks in the shower isn’t much of a dive watch.

Hats off to [Kristopher] for doing the work here. We always love citizen science efforts such as this, whether it’s hardware-free radio astronomy or sampling whale snot with a drone.

Continue reading “Torturing An Instrumented Dive Watch, For Science” →

The Arduboy, Ported To Desktop And Back Again

July 18, 2019 by 21 Comments

A neat little hacker project that’s flying off the workbenches recently is the Arduboy. This tiny game console looks like a miniaturized version of the O.G. Game Boy, but it is explicitly designed to be hacked. It’s basically an Arduino board with a display and a few buttons, anyway.

[rv6502] got their hands on an Arduboy and realized that while there were some 3D games, there was nothing that had filled polygons, or really anything resembling a modern 3D engine. This had to be rectified, and the result is pretty close to Star Fox on a microcontroller.

This project began with a simple test on the Arduboy to see if it would be even possible to render 3D objects at any reasonable speed. This test was just a rotating cube, and everything looked good. Then began a long process of figuring out how fast the engine could go, what kind of display would suit the OLED best, and how to interact in a 3D world with limited controls.

Considering this is a fairly significant engineering project, the fastest way to produce code isn’t to debug code on a microcontroller. This project demanded a native PC port, so all the testing could happen on the PC without having to program the Flash every time. That allowed [rv] to throw out the Arduino IDE and USB library; if you’re writing everything on a PC and only uploading a hex file to a microcontroller at the end, you simply don’t need it.

One of the significant advances of the graphics capability of the Arduboy comes from exploring the addressing modes of the OLED. By default, the display is in a ‘horizontal mode’ which works for 2D blitting, but not for rasterizing polygons. The ‘vertical addressing mode’, on the other hand, allows for a block of memory, 8 x 128 bytes, that maps directly to the display. Shove those bytes over, and there’s no math necessary to display an image.

This is, simply, one of the best software development builds we’ve seen. It’s full of clever tricks (like simply not doing math if you’ll never need the result) and stuffing animations into far fewer bytes than you would expect. You can check out the demo video below.

Continue reading “The Arduboy, Ported To Desktop And Back Again” →

BornHack Tease Us With Their Badge

July 17, 2019 by No comments

Every August for the past four years, there has been a summer hacker camp on the Danish island of Bornholm, that may be a relatively new kid on the block but is slowly evolving into one of the summer’s essential stop-offs. This year for the first time they are moving to a larger site in an easier-to-reach part of the country, and in the usual build-up to the event they have released a teaser image of their badge.

Of course, you will want to know a little more about it than the picture can convey, so the BornHack folks were kind enough to give us a few more details. At its heart is a Silicon Labs Happy Gecko EFM32HG322F64G microcontroller, the same 25 MHz ultra-low-power ARM Cortex M0+ part that has featured in the previous BornHack offerings. Power comes from a pair of AA cells, and it sports a 240 x 240 pixel colour IPS display and an SD card holder. Connectivity is via USB and an infra-red interface for badge-to-badge communication, and human interface is via a mini joystick switch. Finally, it has a six-way v1.69bis Shitty Addon connector.

By some standards this is a relatively modest offering, but by using an evolution of their hardware from previous years as well as the same proven Geckoboot bootloader they are far more likely to deliver a satisfactory user experience than had they opted for a more ambitious design. We’ll be attending the camp, so we’ll report on the finished article once we have it.

BornHack will run from the 8th to the 15th of August, on the Danish island of Funen. There are a range of tickets still available, from single day visits to the whole week for 1200 DKK (about €160, or $181). Compared to some other events on our community’s calendar, we think that represents a bargain.