A $4 Ultrasonic Theremin Looks Cheesy on Purpose

We don’t think [bleepbit] will take offense when we say the “poor man’s theremin” looks cheesy — after all, it was built in a cheese container. Actually, it isn’t a bad case for a simple device, as you can see in the picture and the video below. Unlike a traditional theremin, the device uses ultrasonics to detect how far away your hand is and modifies the sound based on that.

There are also two buttons — one to turn the sound off and another to cycle through some effects. We liked how it looked like a retro cassette, though. The device uses a cheap Arduino clone, but even with a real Arduino, the price wouldn’t be too bad. However, the price tag quoted doesn’t include a few connectors or the speaker that appears in the schematic. There’s a note that the model built uses a jack instead of a speaker, but it would be nice to include both and use the kind of jack that disconnects the speaker when you plug speakers or headphones in.

Continue reading “A $4 Ultrasonic Theremin Looks Cheesy on Purpose”

Yellow Robot Wheels Rolling Out

Small wheeled robots are great for exploring robotics and it’s easier than ever to get started, thanks to growing availability and affordability of basic components. One such component is a small motorized wheel assembly commonly shown when searching for “robot wheel”: a small DC motor mounted in a gearbox to drive a single plastic wheel (inevitably yellow) on which a thin rubber tire has been mounted for traction. Many projects have employed these little motor + gearbox + wheel modules, such as these three entries for 2018 Hackaday Prize:

BoxBotics takes the idea of an affordable entry point and runs with it: build robot chassis for these wheels out of cardboard boxes. (Maybe even the exact box that shipped the yellow wheels.) Cardboard is cheap and easy to work with, making cardboard projects approachable to any creative mind. There will be an audience for something like a Nintendo Labo for robotics, and maybe BoxBotics will grow into that offering.

Cing also intends to make a friendly entry point for robotics and they offer a different chassis solution. Instead of cardboard, they use a circuit board. The yellow gearbox is mounted directly to the main circuit board making it into the physical spine, along with its copper traces serving as the spinal cord of the robot. While less amenable to mechanical creativity than BoxBotics, Cing’s swappable modules might be a better fit for those interested in exploring electronics.

ROS Starter Robot caters to those who wish to go far beyond simple “make it move” level of robot intelligence. It aims to lower the barrier to enter the world of ROS (robot operating system) which has historically been the domain of very capable (but also very expensive) research-oriented robots. This project could become the bridge for aspiring roboticists who wish to grow beyond hobbyist level software but can’t justify the cost typical of research level hardware.

All three of these projects take the same simple motorized wheel and build very different ideas on top of them. This is exactly the diversity of ideas we want to motivate with the Hackaday Prize and we hope to see great progress on all prize contestants in the month ahead.

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? 

What’s the Best Way to Learn Electronics?

What’s the best way to learn electronics? It’s a pithy question to ask a Hackaday audience, most of whom are at least conversant in the field already. Those who already have learned often have just their own perspective to draw upon—how they themselves learned. Some of you may have taught others. I want to explore what works and what doesn’t.

Hobbyists Learn Differently Than Students

One thing I can say straight off is that students learn differently than people who learn at home. Hobbyists have the advantage of actually being interested, which is a quality a student may not enjoy. People have been teaching themselves electronics since the beginning, with analog projects–Heathkit models, BEAM robots, and ham radio sets–evolving into purely digital projects.

Let’s face it, Arduinos lower the bar like nothing else. There’s a reason why the Blink sketch has become the equivalent to “Hello World”. Dirt cheap and easily configured microcontrollers combined with breakout boards make it easy for anyone to participate.

However, ask any true EE and that person will tell you that following wiring diagrams and plugging in sensor boards from Sparkfun only teaches so much. You don’t bone up on terms like hysteresis or bias by building something from uCs and breakout boards. But do you need to? If you are truly interested in electronics and learn by making those Adafruit or Sparkfun projects, sooner or later you’ll want to make your own breakout boards. You’ll learn how to design your own circuit boards and figure out why things work and why they don’t. I don’t need to tell you the Internet has all the answers a neophyte needs–but the interest has to be there in the first place.

What’s the Best Way to Learn in the Classroom?

There is a product category within robotics kits that consists of “educational rovers” designed to be purchased in group lots by teachers so that each student or small group gets one. These rovers are either pre-built or mostly built—sure, you get to screw in motor mounts, but all the circuit boards are already soldered up for you, surface mount, no less. They come pre-configured for a variety of simple tasks like line following and obstacle avoidance. The Makeblock mBot is an example.

I think it’s part of that whole “learn coding” initiative, where the idea is to minimize the assembly in order to maximize the coding time. Insofar as soldering together a kit of through-hole components teaches about electronics, these bots mostly don’t do it. By all appearances, if there is a best way to learn electronics, this an’t it. However, regardless of what kind of project the teacher puts in front of the student, it still has to generate some sort of passion. What those robots provide is a moment of coolness that ignites the firestorm of interest.

I once led a soldering class that used Blinky Grids by Wayne and Layne as the focus. This is a fantastic kit that guides you through building a small LED matrix. It’s particularly cool because it can be programmed over a computer monitor with light sensors interacting with white and black squares on the company’s web site. When my students finished their grids, they all worked and had unique messages scrolling through. Now, that is a payoff. I’m not saying that any of those folks became hardware hackers as a result of my class, but it beat the hell out of a Christmas tree, am I right?

Getting back to that rover, what must be acknowledged is that the rover itself is the payoff, and that’s only as far as it goes if everyone loses interest. However, a lot of those rovers have expansion possibilities like bolting on another sensor or changing the method of programming–for instance, the mBot has both a graphic programming interface and can also be reflashed with a regular old Arduino bootloader.

Readers, share in comments your own perspective. How did you learn? How would you teach others?

Death, Taxes, and Laundry

There’s an old saying that the only two things that are certain are death and taxes. However, unless you live in a nudist colony, there’s probably also laundry. [Darpan Bajaj] and some friends were at a hackathon and decided to put their washing machine on the Internet.

Most of us here at Hackaday — and many Hackaday readers, judging by the comments — are a little suspicious about how much we really need everything attached to the Internet. However, a washing machine is probably not a bad idea: you use it often, you need to know when it is done, and you probably don’t want to just sit and watch it spin. Besides, the intended installation is in a hostel where there are multiple machines and many potential users.

Continue reading “Death, Taxes, and Laundry”