Save A Few Steps On Your Next Build With These Easy Linear Actuators

November 2, 2018 by Dan Maloney 18 Comments

A lot of projects require linear motion, but not all of them require high-accuracy linear slides and expensive ball screws. When just a little shove for a door or the ability to pop something up out of an enclosure is all you need, finding just the right actuator can be a chore.

Unless someone has done the work for you, of course. That’s what [Ali] from PotentPrintables did with these 3D-printed linear actuators. It’s a simple rack-and-pinion design that’s suitable for light loads and comes in two sizes, supporting both the 9-g micro servos and the larger, more powerful version. Each design has a pinion that has to be glued to a servo horn, and a selection of rack lengths to suit your needs. The printed parts are nothing fancy, but seem to have material in the right places to bear the loads these actuators will encounter. [Ali] has included parts lists and build instructions in with the STL files, as well as sample Arduino code to get you started. The video below shows the actuators in action.

We’re heartened to learn that [Ali] was at least partly inspired to undertake this design by a previous Hackaday post. And we’re glad he decided to share his version; it might save us a few steps on our next build.

Continue reading “Save A Few Steps On Your Next Build With These Easy Linear Actuators” →

Robot + Trumpet = Sad Trombone.mp3

October 22, 2018 by Kristina Panos 13 Comments

[Uri Shaked] is really into Latin music. When his interest crescendoed, he bought a trumpet in order to make some energetic tunes of his own. His enthusiasm flagged a bit when he realized just how hard it is to get reliably trumpet-like sounds out of the thing, but he wasn’t about to give up altogether. Geekcon 2018 was approaching, so he thought, why not make a robot that can play the trumpet for me?

He scoured the internet and found that someone else had taken pains 20 years ago to imitate embouchure with a pair of latex lips (think rubber glove fingers filled with water). Another soul had written about measuring air flow with regard to brass instruments. Armed with this info, [Uri] and partners [Ariella] and [Avi] spent a few hours messing around with air pumps, latex, and water and came up with a proof of concept that sounds like—and [Uri]’s description is spot-on—a broken robotic didgeridoo. It worked, but the sound was choppy.

Fast forward to Geekcon. In a flash of brilliance, [Avi] thought to add capacitance to the equation. He suggested that they use a plastic box as a buffer for air, and it worked. [Ariella] 3D printed some fingers to actuate the valves, but the team ultimately ended up with wooden fingers driven by servos. The robo-trumpet setup lasted just long enough to get a video, and then a servo promptly burned out. Wah wahhhh. Purse your lips and check it out after the break.

If [Uri] ever gets fed up with the thing, he could always turn it into a game controller a la Trumpet Hero.

Continue reading “Robot + Trumpet = Sad Trombone.mp3” →

Laser Cut Cardboard Robot Construction Kit Eases Learning And Play

October 18, 2018 by Donald Papp No comments

It has never been easier to put a microcontroller and other electronics into a simple project, and that has tremendous learning potential. But when it comes to mechanical build elements like enclosures, frames, and connectors, things haven’t quite kept the same pace. It’s easier to source economical servos, motors, and microcontroller boards than it is to arrange for other robot parts that allow for cheap and accessible customization and experimentation.

That’s where [Andy Forest] comes in with the Laser Cut Cardboard Robot Construction Kit, which started at STEAMLabs, a non-profit community makerspace in Toronto. The design makes modular frames, enclosures, and basic hardware out of laser-cut corrugated cardboard. It’s an economical and effective method of creating the mechanical elements needed for creating robots and animatronics while still allowing easy customizing. The sheets have punch-out sections for plastic straws, chopstick axles, SG90 servo motors, and of course, anything that’s missing can be easily added with hot glue or cut out with a knife. In addition to the designs being open sourced, there is also an activity guide for educators that gives visual examples of different ways to use everything.

Cardboard makes a great prototyping material, but what makes the whole project sing is the way the designs allow for easy modification and play while being easy to source and produce.

Mechatronic Hand Mimics Human Anatomy To Achieve Dexterity

October 18, 2018 by Dan Maloney 8 Comments

Behold the wondrous complexity of the human hand. Twenty-seven bones working in concert with muscles, tendons, and ligaments extending up the forearm to produce a range of motions that gave us everything from stone tools to symphonies. Our hands are what we use to interface with the physical world on a fine level, and it’s understandable that we’d want mechanical versions of ourselves to include hands that were similarly dexterous.

That’s a tall order to fill, but this biomimetic mechatronic hand is a pretty impressive step in that direction. It’s [Will Cogley]’s third-year university design project, which he summarizes in the first video below. There are two parts to this project; the mechanical hand itself and the motion-capture glove to control it, both of which we find equally fascinating. The control glove is covered with 3D-printed sensors for each joint in the hand. He uses SMD potentiometers to measure joint angles, with some difficulty due to breakage of the solder joints; perhaps he could solve that with finer wires and better strain relief.

The hand that the glove controls is a marvel of design, like something on the end of a Hollywood android’s arm. Each finger joint is operated by a servo in the forearm pulling on cables; the joints are returned to the neutral position by springs. The hand is capable of multiple grip styles and responds fairly well to the control glove inputs, although there is some jitter in the sensors for some joints.

The second video below gives a much more detailed overview of the project and shows how [Will]’s design has evolved and where it’s going. Anthropomorphic hands are far from rare projects hereabouts, but we’d say this one has a lot going for it.

Continue reading “Mechatronic Hand Mimics Human Anatomy To Achieve Dexterity” →

Popup Notification Dinosaur

October 18, 2018 by Bryan Cockfield 1 Comment

There’s a lot going on our virtual spaces, and anyone with a smart phone can attest to this fact. There are pop-up notifications for everything you can imagine, and sometimes it’s possible for the one really important notification to get lost in a sea of minutiae. To really make sure you don’t miss that one important notification, you can offload that task to your own personal dinosaur.

The 3D-printed dinosaur has a rack-and-pinion gear set that allows it to extend upwards when commanded. It also has a set of LEDs for eyes that turn on when it pops up. The two servos and LEDs are controlled by a small Arduino in the base of the dinosaur. This Arduino can be programmed to activate the dinosaur whenver you like, for an email from a specific person, a reply to a comment on Reddit, or an incoming phone call to name a few examples. Be sure to check out the video below the break.

With this dinosaur on your desk, it’s not likely you’ll miss its activation. If you’d like something that has the same function but with less movement and more lights, there’s also a notification 3D cube made out of LEDs that’s sure to catch your eye as well. Continue reading “Popup Notification Dinosaur” →

The Crustacean Battle Bot Of Your Nightmares

October 11, 2018 by Tom Nardi 10 Comments

We’ve all seen a movie or TV show that got our imagination going, and the more studious of us might get fired up over a good book (one without pictures, even). You never know were inspiration might come from, which is why it’s so hard to track down in the first place. But one place we don’t often hear about providing many hackers with project ideas is the grocery store. But of course the more we learn about [Michael Kohn], the more we realize he’s got a very unique vision.

On a recent trip to the grocery store, [Michael] saw a two pack of frozen lobsters and thought they would make fine battling robots. You know, as one does. Unfortunately the process of taking a frozen lobster and turning it into a combat droid (which incidentally does include eating the thing at some point in the timeline) ended up being so disgusting that he only finished one of them. Whether that makes this poor fellow the winner or loser though…that’s a question that will require some contemplation.

The first step was cooking and eating the beast, and after that came cleaning the shell of as much remaining meat and innards as possible. He then baked it in a toaster oven for 40 minutes and let it sit for a couple of days to make sure it didn’t have any residual smell. Once he confirmed the shell was clean, he glued it back together and got started on mounting it to his hardware.

A wooden frame under the lobster holds the dual HD-1711MG mini servos that power the karate chop action of the claws, as well as the electronics. [Michael] used a ATtiny85 and NTD4963N MOSFETs to make a basic RC platform which responds to IR from a Syma S107 toy helicopter controller. He tried to power everything with AAA and then AA batteries, but found they just didn’t give him the juice he needed once the bot got going. So the final version utilizes a 5 V regulator and a standard RC 7.2v LiPO battery pack.

If you’re not big on shellfish, never fear. He’s created similar roving contraptions based around sausages and carrots too. One could say he’s truly a man of refined…taste.

Continue reading “The Crustacean Battle Bot Of Your Nightmares” →

Watch The Snappy, Insect-like Moves Of This DIY Quadruped Robot

September 30, 2018 by Donald Papp 28 Comments

Some legged robots end up moving with ponderous deliberation, or wavering in unstable-looking jerks. A few unfortunates manage to do both at once. [MusaW]’s 3D Printed Quadruped Robot, on the other hand, moves in rapid motions that manage to look sharp and insect-like instead of unstable. Based on an earlier design he made for a 3D printable quadruped frame, [MusaW] has now released this step-by-step guide for building your own version. All that’s needed is the STL files and roughly $50 in parts from the usual Chinese resellers to have the makings of a great weekend project.

The robot uses twelve SG90 servos and an Arduino nano with a servo driver board to control them all, but there’s one additional feature: Wi-Fi control is provided thanks to a Wemos D1 Mini (which uses an ESP-8266EX) acting as a wireless access point to serve up a simple web interface through which the robot can be controlled with any web browser.

Embedded below is a brief video. The first half is assembly, and the second half demonstrates the robot’s fast, sharp movements.

Continue reading “Watch The Snappy, Insect-like Moves Of This DIY Quadruped Robot” →