Posts with «arduino hacks» label

Rock ‘n Roll With 3D-Printed Tonewheels

What can you do with ferromagnetic PLA? [TheMixedSignal] used it to give new meaning to the term ‘musicians’ gear’. He’s made a proof of concept for a DIY tone generator, which is the same revolutionary system that made the Hammond organ sing.

Whereas the Hammond has one tonewheel per note, this project uses an Arduino to drive a stepper at varying speeds to produce different notes. Like we said, it’s a proof of concept. [TheMixedSignal] is proving that tonewheels can be printed, pickups can be wound at home, and together they will produce audible frequencies. The principle is otherwise the same — the protruding teeth of the gear induce changes in the magnetic field of the pickup.

[TheMixedSignal] fully intends to expand on this project by adding more tone wheels, trying different gear profiles, and replacing the stepper with a brushless motor. We can’t wait to hear him play “Karn Evil 9”. In the meantime, put on those cans and check out the demo/build video after the break.

We don’t have to tell you how great Hammond organs are for making music. But did you know they can also encode secret messages?

Via the Arduino blog.

The Open Source Smart Home

[Tijmen Schep] sends in his project, Candle Smart Home, which is an exhibit of 12 smart home devices which are designed around the concepts of ownership, open source, and privacy.

The central controller runs on a Raspberry Pi which is running Mozilla’s new smart home operating system. Each individual device is Arduino based, and when you click through on the site you get a well designed graphic explaining how to build each device. The devices them

It’s also fun to see how many people worked together on this project and added their own touch. Whether it’s a unique covering for the devices or a toggle switch that can toggle itself there’s quite a few personal touches.

As anyone who’s had the sneaking suspicion that Jeff Bezos was listening in to their conversations, we get the need for this. We also love how approachable it makes hacking your own hardware. What are your thoughts?

Hack a Day 07 Nov 03:00

Godot Machine is the Project You’ve Been Waiting For

Are you waiting for something that may never happen? Maybe it’s the end of your ennui, or the release of Half Life 3. While you wait, why not build a Godot Machine? Then you can diversify your portfolio and wait for two things that could happen today, tomorrow, or at sunrise on the 12th of Never.

The Godot Machine is a functional art piece that uses a solar panel and a joule thief to charge a bank of capacitors up to 5V. Whenever that happens, the Arduino comes online and generates a 20-bit random number, which is displayed on an LED bar. If the generated number matches the super-secret number that was generated at first boot and then stashed away in EEPROM, the Machine emits a victory beep and lights a green LED. Then you can go back to complaining about whatever.

We like that [kajnjaps] made his own chaos-based random number generator instead of just calling random(). It uses a guitar string to collect ambient electronic noise and an entropy generator to amplify it. Then the four least significant digits are used to seed the logistical map, so the initial value is always different.

You don’t have to create your own entropy for truly random numbers, though it’s probably more fun that way. Did you know that someone wrote an Arduino entropy library?

Electricity Makes Soft Robotics More Like Us Meatbags

Building a future where robots work alongside humans relies heavily on soft robotics. Typically this means there will be an air compressor or a hydraulic system nearby, taking up precious space. But it doesn’t have to.

Engineers at the UC-San Diego Jacobs School have created a soft robotics system that uses electricity to control flexible actuators, much like our brains move our muscles. It works like this: sheets of heat-sensitive liquid crystal elastomer are sandwiched between two layers of standard elastomer. These layers are rolled into cylinders that can twist and bend in different directions depending on which of its six element(s) get electricity. Light up all six, and the tube contracts, forming the foundation for a good gripper. The team also built a tiny walker, pictured above.

The project is still in its infancy, so the actuators are slow to bend and even slower to return to their original shape, but it’s still a great start. Imagine all the soft robotic projects that can get off the ground without being shackled by the bulk and weight of an air compressor or fluid handling system. Watch it do various sped-up things after the break, like claw-machine gripping a bottle of chocolate rocks.

Speaking of delicious candy, edible soft robotics is totally a thing.

Via Arduino blog

Haptic Glove Controls Robot Hand Wirelessly

[Miller] wanted to practice a bit with some wireless modules and wound up creating a robotic hand he could teleoperate with the help of a haptic glove. It lookes highly reproducible, as you can see the video, below the break.

The glove uses an Arduino’s analog to digital converter to read some flex sensors. Commercial flex sensors are pretty expensive, so he experimented with some homemade sensors. The ones with tin foil and graphite didn’t work well, but using some bent can metal worked better despite not having good resolution.

The wireless communications set up was pretty easy thanks to the NRF24L01 modules. The hard part was sewing the flex sensors into the glove. We thought some of the circuitry looked precarious on the glove, too.

For the robot hand, he used balsa wood and hinges for each joint. Flexible thread provided the return power like a spring. The hand was surprisingly artistic in a primitive sort of way.

While this is a cool demo, the hand isn’t likely to be practical for much as it is. Nerve impulses are better but harder. The glove reminded us a little of one we’d seen before.

Hang Ten With Help From the Surf Window

Unless you live in a special, unique place like Hawaii or Costa Rica it’s unlikely you’ll be able to surf every day. It’s not easy to plan surf sessions or even surf trips to most locations because the weather conditions will need to be just right. Not only the wave height (swell) but also the wind speed and direction, tide, water and air temperature, and even amount and type of marine life present can all impact your surf session. You’ll want something which can easily tell you right away if conditions are good.

This project from [luke] is called the Surf Window shows the surf conditions at the local beach with just one glance. Made out of various pieces of wood, each part represents one of the weather conditions at the beach. A rotating seagull gives the wind direction, for example, and the wave height is represented by 3D, moving waves. All of the parts are connected with various motors and linkages to an Arduino Mega +WiFi R3 which grabs all of its information from Magicseaweed, a surf forecasting site.

The Surf Window can show the current conditions at virtually any surfable beach in the world, so if you really want to know how Jaws, Mavericks, or even Reef Road is breaking right now, you could use this to give you a more nuanced look. Don’t forget to take the correct board for the conditions!

Steering By Touch And Haptic Feedback

Scribble is a haptic interface lets you draw your way through traffic. In an environment where fully automated vehicles are becoming the expectation for the next step in transportation, Scribble provides a friendly alternative that allows you to guide your car around, while the automation makes decisions on how to actually steer the car around obstacles.

The driver is guided by haptic feedback that alerts them about the road conditions or obstacles ahead. The project was conceived by [Felix Ros] for his master’s thesis at Eindhoven University, featured a five bar linkage that moves with two lateral degrees of freedom, commonly used for drawing robots.

The code run on an Arduino DUE control over serial by a program made in Open Frameworks that communicates with a Unity 3D driving simulator over UDP. Fellow graduate student [Frank van Valeknhoef]’s Haptic Engines are used as the actuators, outputting the position and a variable force.

The forward kinematics algorithms were based on a clock and weather plotter by SAP, sharing the same servo and drawing arm assembly. The left and right actuators update based on the desired angle, calculating the proper angles needed to achieve the correct position.

While automated vehicles may be able to travel efficiently from one destination to the next, they can’t necessarily wander off course to explore new places. Scribble takes back some of that freedom and allows drivers to decide for themselves where they want to be. It’s an interesting take at inserting the human back into the driver’s seat in automated cars.

The Arduino IDE Finally Grows Up

While the Arduino has a very vocal fan club, there are always a few people less than thrilled with the ubiquitous ecosystem. While fans may just dismiss it as sour grapes, there are a few legitimate complaints you can fairly level at the stock setup. To address at least some of those concerns, Arduino is rolling out the Arduino Pro IDE and while it doesn’t completely address every shortcoming, it is worth a look and may grow to quiet down some of the other criticisms, given time.

For the record, we think the most meaningful critiques fall into three categories: 1) the primitive development environment, 2) the convoluted build system, and 3) the lack of debugging. Of course, there are third party answers for all of these problems, but now the Pro IDE at least answers the first one. As far as we can tell, the IDE hides the build process just like the original IDE. Debugging, though, will have to wait for a later build.

We were happy to see a few things with the new IDE. There’s some autocompletion support, Git is integrated, and there’s still our old friend the serial monitor. The system still uses the Arduino CLI, so that means there isn’t much danger of the development getting out of sync. The actual editor is Eclipse Theia. People typically either love Eclipse or hate it, however, it is at least a credible editor. However, Theia uses Electron which makes many people unhappy because Electron applications typically eat a lot of resources. We’ll have to see how taxing using the new Pro IDE is on typical systems with normal workloads.

On the future feature list is our number one pick: debugging. They are also promising support for new languages, third party plugins, and synchronization with the Web-based editor. All good features.

This is just an alpha preview release, but it is a great start. Our only question is will existing users really care? Most people already write code in another editor. Many use an external build system like PlatformIO. Eclipse already has a plug in for Arduino that supports debugging with the right hardware. So while new users may appreciate the features, advanced users may be wondering why this is so late to the party.

 

Hack a Day 21 Oct 12:00

Arduino Wire Bender Probably Won’t Kill All Humans

Do you want to make your own springs? Yeah, that’s what we thought. Well, blow the dust off of that spare Arduino and keep reading. A few months ago, we let you know that renowned circuit sculptor [Jiří Praus] was working on a precision wire-bending machine to help him hone his craft. Now it’s real, it’s spectacular, and it’s completely open source.

Along with that ‘duino you’ll need a CNC shield and a couple of NEMA 17 steppers — one to feed the wire and one to help bend it. Before being bent or coiled into springs, the wire must be super straight, so the wire coming off the spool holder runs through two sets of rollers before being fed into the bender.

[Jiří]’s main goal for this build was precision, which we can totally get behind. If you’re going to build a machine to do something for you, ideally, it should also do a better job than you alone. It’s his secondary goal that makes this build so extraordinary. [Jiří] wanted it to be easy to build with commonly-available hardware and a 3D printer. Every part is designed to be printed without supports. Bounce past the break to watch the build video.

You can also make your own springs on a lathe, or print them with hacked g-code.

Review: OSEPP STEM Kit 1, a Beginner’s All-in-One Board Found in the Discount Aisle

As the name implies, the OSEP STEM board is an embedded project board primarily aimed at education. You use jumper wires to connect components and a visual block coding language to make it go.

I have fond memories of kits from companies like Radio Shack that had dozens of parts on a board, with spring terminals to connect them with jumper wires. Advertised with clickbait titles like “200 in 1”, you’d get a book showing how to wire the parts to make a radio, or an alarm, or a light blinker, or whatever.

The STEM Kit 1 is sort of a modern arduino-powered version of these kits. The board hosts a stand-alone Arduino UNO clone (included with the kit) and also has a host of things you might want to hook to it. Things like the speakers and stepper motors have drivers on board so you can easily drive them from the arduino. You get a bunch of jumper wires to make the connections, too. Most things that need to be connected to something permanently (like ground) are prewired on the PCB. The other connections use a single pin. You can see this arrangement with the three rotary pots which have a single pin next to the label (“POT1”, etc.).

I’m a sucker for a sale, so when I saw a local store had OSEPP’s STEM board for about $30, I had to pick one up. The suggested price for these boards is $150, but most of the time I see them listed for about $100. At the deeply discounted price I couldn’t resist checking it out.

So does an embedded many-in-one project kit like this one live up to that legacy? I spent some time with the board. Bottom line, if you can find a deal on the price I think it’s worth it. At full price, perhaps not. Join me after the break as I walk through what the OSEPP has to offer.

What’s Onboard?

There are plenty of input and output devices:

  • 7 Push Buttons
  • Potentiometers (3 rotary and 1 slide)
  • Passive Infrared Sensor (PIR)
  • Light Sensor
  • Sound Sensor
  • LM35 Temperature Sensor
  • 10 LEDs (various colors)
  • Servo Motor
  • Stepper Motor
  • DC Motor
  • LCD Display
  • Buzzer
  • Speaker
  • RGB LED

In addition, the kit comes with an ultrasonic distance sensor in a little bracket that can connect to the stepper motor. That’s the only part that needs power and ground that isn’t already wired up.

Because the heart of the board is an Arduino UNO clone, you can do anything you like to program it. However, OSEPP touts their visual block diagram language that is basically Scratch. You can use it for free on most platforms and there is even a Web-based version although it can’t download code. It looks like Scratch or other block-oriented systems you’ve seen before.

I’m not usually fond of the visual block languages, but this one at least shows you the actual Arduino code it generates, so that isn’t bad. But you can still use any other method you like such as the standard IDE or PlatformIO.

You can see a video about the board, below.

The Good and the Bad

The board feels substantial and able to withstand a good bit of abuse. There’s a good range of components, and I like that the arduino is a real daughter board and not just built onto the PCB. Despite using the block language, I do like the tutorial booklet. It is very slick and has projects ranging from an IR doorbell to a mini piano. You can see a page below — very colorful and clear.

Of course, the suggested retail price of $150 is a bit offputting. You might think a breadboard with a handful of LEDs and other parts would be a much lower-cost option but just look around for arduino kits for beginners and you’ll find prices are all over the place. On the other hand, with a parts kit you would have to know how to wire up things like stepper motors or DC motors, so there is some value to having it already done for you. There’s also value in not having a bag of parts to misplace.

The jumper wires in the kit have pins on one side and sockets on the other. The pins go into the Arduino’s connector and the sockets go over pins on the components. These aren’t quite as reliable as a spring clip and not as versatile either.

In my mind the worst part of the kit design is that the pins are right next to each of the components. That’s good for understanding, but it makes a mess of wiring. For instance, there are ten LEDs, and connecting them all means stretching jumper wires to both edges of the board The jumpers aren’t very long either, so any complex project is going to have wires crisscrossing the sensors and LCD.

Granted, in this image I could have removed some of the wires from the bundles but that wouldn’t help that much, either. If you need to hook up more than a few of the available components you will have a mess. I would have put some sort of spring clip or even screw terminals and put them all on the top and bottom of the board with clear color-coded marking about where they connect. Then the wiring would all be out of the way. There are probably a few other ways they could have gone, and at this price, they could afford the few extra inches on the PCB.

There are a few other things that would have been nice touches to finish off this kit. I would have enjoyed a short chapter in the booklet about using the Arduino IDE directly so that people know it exists. And having even a small breadboard attached for your own exploration would make sense, but would then call for a different type of jumper wire.

Short Example Using the Distance Sensor

I wanted to do something with the board so I decided to play with the distance sensor and the servo. The distance sensor is a bit annoying both because you have to wire it all up and it has a tendency to fall off when you transport the board.

The demo (you can find it online) won’t win any originality prizes. The program moves the servo to scan from 0 to 180 degrees in 5 degree increments. It measures the distance of what’s in front of it. When it completes a scan, if it saw something close (you could adjust the sensitivity), it moves the sensor back to that position and waits 30 seconds. Otherwise, it keeps scanning.

Really, this is no different from any other Arduino program. That’s kind of the point. Despite the emphasis in the book on the point-and-click language, this is really just an Arduino.

In Summary

For the deep sale price I found, the board will work well for its intended audience of students or anyone starting out with Arduino or microcontrollers. Even a more advanced audience who just wants a way to hammer out a quick prototype might find it worth the $30 or $40 you can sometimes pay. But at full price, it is hard to imagine this makes sense because of the mess of wire routing and limited expansion options.