Papercraft-Inspired Snake-bot Slithers Like A Real One

Blend the Japanese folding technique of Kirigami with an elastomer actuator, and what have you got? A locomoting snake robot that can huff around its own girth with no strings attached! That’s exactly what researchers at the Wyss Institute and Harvard School of Applied Sciences did to build their Kirigami Crawler.

Expanding and contracting propel this crawler forward. As the actuator expands, the hatched pattern on the plastic skin flares out; and when it contracts, the skin retracts to a smoother form. The flared hatch pattern acts like a cluster of little hooks, snagging multiple contact points into the ground. When the skin retracts, these hooks fold back inside while giving the body a slight push forward in the process. It’s a clever tactic, and almost identical to the way real-world snakes propel themselves. In fact, after iterating on a few skin patterns, they found that a trapezoidal pattern, which most closely resembles that of snakeskin, can cover ground fastest.

We’re thrilled to see such authentic biomimicry come to us without any extreme tooling or special molds. Still not satisfied with your share of crawling robots for one day? Have a peek into the past, and indulge yourself with a sine-wave locomotion.

Thanks for the tip, [Olivia]!

Continue reading “Papercraft-Inspired Snake-bot Slithers Like A Real One”

Laser Projector Ditches Galvanometer For Spinning Drum

Laser projectors like those popular in clubs or laser shows often use mirror galvanometers to reflect the laser and draw in 2D. Without galvos, and on a tight budget, [Vitaliy Mosesov] decided that instead of downgrading the quality, he would seek an entirely different solution: a spinning mirror drum.

He fires a laser at a rotating drum with twelve mirror faces, each at a different adjustable vertical angle. The laser will hit a higher or lower point on the projection surface depending on which mirror it’s reflecting off – this creates resolution in the Y direction.

Timing the pulsing of the laser so that it reflects off the mirror at a certain horizontal angle provides the X resolution.

As you can already tell, speed and timing is critical for this to work. So much so that [Vitaliy] decided he wanted to overclock his Arduino – from 16 MHz to 24.576 MHz. Since this changes the baud rate, an AVR ISP II was used for programming after the modification, and the ‘duino’s hardware serial initialization had to be hacked too.

For the laser itself, [Vitaliy] designed some nifty driver circuitry, which can respond quickly to the required >50 kHz modulation, supply high current, and filter out voltage transients on the power supply (semiconductor lasers have no protection from current spikes).

On the motor side of things, closed loop control is essential. A photo-interrupter was added to the drum for exact speed detection, as well as a differentiator to clean up the signal. Oh, and did we mention the motor is from a floppy disk drive?

We’ve actually seen builds like this before, including a dot-matrix version with multiple lasers and one made apparently out of Meccano and hot-glue that can project a Jolly Wrencher. But this build, with its multiple, adjustable mirrors, is a beauty.  Check it out in action below.

Continue reading “Laser Projector Ditches Galvanometer For Spinning Drum”

It’s A Spider! It’s A Droideka! It’s Both!

Beware, arachnophobes, the robots are coming for you!

What else would you be expected to think if you watched a hexapod robot display its best Transformers impression by turning into a wheel and pushing itself in your direction? The BionicWheelBot — developed by [Festo] — should rightly remind you of the cartwheeling Flic-Flac spider, the main inspiration for the robot. Of course, Star Wars fans might justifiably see a Droideka.

The BionicWheelBot can — almost — seamlessly transition between crawling around on six legs, to literally rolling away. To do so, its three pairs of legs sequentially fold up into a shape befitting its namesake and then pauses for a moment — almost for dramatic effect — before the real fun begins.

Continue reading “It’s A Spider! It’s A Droideka! It’s Both!”

The Lichtspiel: Not A Simple Child’s Toy.

For his niece’s second birthday, [Stefan] wondered what a toddler would enjoy the most? As it turns out, a box packed with lights, dials and other gadgets to engage and entertain.

For little Alma’s enjoyment, three potentionmeters control a central LED, a row of buttons toggle a paired row of more lights, a rotary encoder to scroll the light pattern of said row left and right, and some sockets to plug a cable into for further lighting effects. Quite a lot to handle, so [Stefan] whipped up a prototype using an Arduino — although he went with an ATmega 328 for the final project — building each part of the project on separate boards and connected with ribbon cables to make any future modifications easier.

[Stefan] attempted to integrate a battery — keeping the Lichtspiel untethered for ease of use — and including a standby feature to preserve battery life. A power bank seemed like a good option to meet the LED’s needed 5V, but whenever the Lichtspiel switched to standby, the power bank would shut off entirely — necessitating the removal of the front plate to disconnect and reconnect the battery every time. The simpler solution was to scrap the idea entirely and use the charging port as a power port instead — much to the delight of his niece who apparently loves plugging it in.

Continue reading “The Lichtspiel: Not A Simple Child’s Toy.”

Carbon Augmented Spider Silk

Some of the creepy-crawlers under our feet, flitting through the air, and waiting on silk webs, incorporate metals into their rigid body parts and make themselves harder. Like Mega Man, they absorb the metals to improve themselves. In addition to making their bodies harder, silk-producing creatures like worms and spiders can spin webs with augmented properties. These silks can be conductive, insulating, or stronger depending on the doping elements.

At Italy’s University of Trento, they are pushing the limits and dosing spiders with single-wall carbon nanotubes and graphene. The carbon is suspended in water and sprayed into the spider’s habitat. After the treatment, the silk is measured, and in some cases, the silk is significantly tougher and surpasses all the naturally occurring fibers.

Commercial spider silk harvesting hasn’t been successful, so maybe the next billionaire is reading this right now. Let’s not make aircraft-grade aluminum mosquitoes though. In fact, here’s a simple hack to ground mosquitoes permanently. If you prefer your insects alive, maybe you also like their sound.

Thank you for the tip, [gippgig].

Nerds Unite: Prosthetics Inspired By Comics And Beyond!

Open Bionics is a company creating prosthetics inspired by heroines, heroes and the fictional worlds they live in. The designs emblazoned on their first set of bionic hands include ones drawn from Queen Elsa from Disney’s Frozen, and Marvel’s Iron Man. The best thing about what they are doing is they offer you, dear reader, a chance to lend your own super powers of design and engineering. Open Bionics offers up 3D print files for several hand designs, hardware schematics and design files for their controller boards, firmware, and software to control the robotic hands with. Other than their website, you can also find all of the files and more on their GitHub account. If you’d like to devote a good amount of time and become a developer, they have a form to contact them through. To help with sourcing parts for your own build, they sell cables for tendons, muscle sensors, and fingertip grips in their online store

 We first came to learn about this company through a tipster [Dj Biohazard] who pointed to a post about their partnership with an 11-year-old Tilly, who is pictured on the left. Her bionic hand is an Open Bionics prototype whose design is based on the video game, Deus Ex. The best way products like these are improved are through the open source community and people like her.

Specific improvements Open Bionics state on their website are:

  • The customised bionic arms are manufactured in under 24 hours and the revolutionary socket adjusts as the child grows.
  • The bionic arms are light and small enough for those as young as eight.
  • The bionic arms use myoelectric skin sensors to detect the user’s muscle movements, which can be used to control the hand and open and close the fingers.

Read more about Tilly’s story and her partnership with Open Bionic’s on Womanthology. Tilly seems to have a dream of her own to “make prosthetics a high fashion piece – something that amputees can be proud to wear.” 

We at Hackaday have written about several open source prosthetic developments such as a five-day event S.T.E.A.M. Fabrikarium program taking place at Maker’s Asylum in Mumbai and the work of [Nicholas Huchet]What superhuman inspired designs would you create? 

3D Printed Battery Pack Keeps Old Drill Spinning

The greatest enemy of proprietary hardware and components is time. Eventually, that little adapter cable or oddball battery pack isn’t going to be available anymore, and you’re stuck with a device that you can’t use. That’s precisely what happened to [Larry G] when the now antiquated 7.2V NiCd batteries used by his cordless drill became too hard to track down. The drill was still in great shape and worked fine, but he couldn’t power the thing. Rather than toss a working tool, he decided to 3D print his own battery pack.

The 3D modeling on the battery pack is impeccable

He could have just swapped new cells into his old pack, but if you’re going to go through all that trouble, why not improve on things a little? Rather than the NiCd batteries used by the original pack, this new pack is designed around readily available AA NiMH batteries. For the light repairs and craft work he usually gets himself into, he figures these batteries should be fine. Plus he already had them on hand, and as we all know, that’s half the battle when putting a project together.

Interestingly, the original battery pack was wired in such a way that it provided two voltages. In older tools such as this one, this would be used for rudimentary speed control. Depending on which speed setting the drill is on, it would either connect to 4 or 6 cells in the original pack. [Larry] didn’t want to get involved with the extra wiring and never used the dual speeds anyway, so his pack only offers the maximum speed setting. Though he does mention that it may be possible to do PWM speed control in the battery itself via a 555 timer if he feels like revisiting the project.

[Larry] tells us the pack itself was rendered completely from scratch, using only the original battery pack and trial-and-error to get the fit perfect. He reused the side-mounted release buttons to save time, but otherwise everything is 3D printed in PETG for its strength and chemical resistance.


This is an entry in Hackaday’s

Repairs You Can Print contest

The twenty best projects will receive $100 in Tindie credit, and for the best projects by a Student or Organization, we’ve got two brand-new Prusa i3 MK3 printers. With a printer like that, you’ll be breaking stuff around the house just to have an excuse to make replacement parts.