Drum machines may seem like one of the many rites of passage for hardware makers, they’re a concept you can implement simply or take into the extreme making it as complex as you want. [Matt’s] DrumKid is one of them, and its long development history is wonderfully documented in the project logs.

[Matt’s] original intention was to use the automatic drummer as part of his band, wanting “the expressiveness of a good drummer but without the robotic tendencies of a simple drum machine”. For that, he created the first iteration of the DrumKid, a web-based project using the Web Audio API. The interface consisted of bars showing levels for different settings which could be intuitively tweaked, changing the probability of a drum sound being played. This gave the “drummer” its unpredictability, setting itself apart from any regular old drum machine.

Fast forward a few years, and [Matt] now wants to recreate his DrumKid as a proper piece of musical gear, porting the concept into a standalone hardware drum machine you can plug into your mixer. He decided to go with the Arduino framework for his project rather than the Teensy platform in order to make it cheaper to build. The controls are simplified down to a few buttons and potentiometers, and the whole thing runs off of three AAA batteries. Also, targeting the project for hardware like this allowed for new features to be added, such as a bit-crush filter.

We already saw the first prototype here on Hackaday when it was featured in a Hackaday Prize mentor session, and it’s nice to see how the project evolved since. After a number of revisions, the new prototype takes design cues from Teenage Engineering’s “Pocket Operator” drum machine, using the main PCB as its own faceplate rather than a 3D printed case in a familiar way we’ve seen before. Unfortunately, the latest board is non-functional due to a routing mistake, but you can see the previous working prototypes in his project logs.

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You (hopefully) take regular showers or baths, but how much water do you use each time you step into your facilities? If you don’t know the answer, then this monitor by LiamOSM could be just what you need.

The device uses a flow sensor plumbed inline with a shower head, which transmits pulses to an Arduino Nano setup. This Nano, which resides in a nicely 3D-printed enclosure, measures these pulses and outputs the amount of water you’ve used to a 16×2 LCD screen, along with its cost calculated according to your particular utility rates. 

Using such a monitor would likely be an eye-opening experience, and the inexpensive flow sensor used here could be a great tool for other projects as well.

Which uses more water – a bath or a shower?

I was recently thinking about this question, and I realized that I don’t actually know how much water is used when I shower. I know when I’m in the shower sometimes my mind wanders, thinking about a cool new projects idea or trying to decide what to have for breakfast, while water is just gushing down the drain. It would be a lot easier to reduce my water consumption if I actually knew how many litres I was using each time!

I did a bit of research, and found that different shower heads can use anywhere from 9.5 litres (2.5 gallons) per minute to less than 6 litres (1.6 gallons) per minute, if you have a flow restrictor installed. A very old shower could use even more water. 

I decided to design and build a device that would display the total volume of water used per shower, the cost of the water, and the flow rate. I’ve had this device installed for a few weeks, and it’s really handy to have a live readout of the amount of water being used.

As seen in the videos below, Zeus is a metallic humanoid robot capable of moving its head and arms around, featuring a pair of hand grippers that should be quite useful when the time comes. For now, creator Luis appears to be focusing on its vocal skills, with plans to eventually teach it how to walk.

The robot can engage in conversation with its companion, whether it’s answering questions like “What’s your name?” with“My name is Zeus,” or “What’s your favorite movie?” with “I wasn’t that impressed with the special effects, also the plot was not deep.” Zeus even lets Luis know when he “has no idea what to say.”

Zeus’ communication and movement are accomplished through a variety of hardware, including an Arduino Mega and an AAEON UP board, as well as an Intel RealSense Camera SR300 for vision. Luis is also using CMUSphinx for voice recognition, eSpeak for text-to-speech and AIML chatbot for interactive responses.

Perhaps we’ll see this ~1/2-sized humanoid traipsing around on its own in the future, though hopefully its comment about “taking over the world” was just a joke!

Ramen noodles can be a quick snack or meal, but per this IoT ramen maker by Clem Mayer, you don’t even have to run to the microwave to prepare them. 

His project used a vintage electric filter coffee machine to heat and dribble water into the waiting brick-o-food, then a stepper-driven pusher adds flavor powder. More seasoning can be dispensed via a servo-actuated syringe, and another stepper is used to stir everything.

The setup is controlled by a MKR WiFi 1010 board, giving Mayer the ability to start meals/mix in hot sauce from the convenience of his phone via a simple web app. Results are… edible-ish, but if you want to build your own, files and more info can be found here.

People love to talk about the weather. It’s the perfect small talk, whether you’re trying to start a conversation or keep one going by avoiding an awkward silence. In the same fashion, weather stations are an ideal starting point for any sort of sensor-related project ideas. You get to familiarizing yourself with communication buses, ADCs, general data acquisition, and you learn a lot in figuring out how to visualize it all.

What if your weather station didn’t visualize anything? [OttoNL] is answering that question with a MIDI-generating Weather Station that uses the mood of the music to convey the condition of the elements outside.

Using an ESP8266 programmed via the Arduino IDE, [OttoNL] hooked up a light dependent resistor, a rain sensor, and the all-round workhorse BME280 for temperature, barometric pressure, and humidity to it. Reading the sensors, the ESP will generate MIDI notes that are sent to a connected synthesizer, with each sensor influencing a different aspect of the generated MIDI signals. A sadder, slow tune will play during rain and a fast upbeat one during sunshine. While it doesn’t use the ESP’s WiFi functionality at all at this point, a future version could easily retrieve some weather forecast data from the internet and add it into the mix as well.

Connect this to your alarm clock, and you can start your day off in the appropriate mood. You can even customize your breakfast toast to really immerse your morning routine in abstract weather cues.

For years [Edward] has been building professional grade underwater sensing nodes at prices approachable for an interested individual without a government grant. An important component of these is temperature, and he has been on a quest to get the highest accuracy temperature readings from whatever parts hit that sweet optimum between cost and complexity. First there were traditional temperature sensor ICs, but after deploying numerous nodes [Edward] was running into the limit of their accuracy. Could he use clever code and circuitry to get better results? The short answer is yes, but the long answer is a many part series of posts starting in 2016 detailing [Edward]’s exploration to get there.

The first step is a thermistor, a conceptually simple device: resistance varies with temperature (seriously, how much more simple can a sensor get?). You can measure them by tapping the center of a voltage divider the same way you’d measure any other resistance, but [Edward] had discarded this idea because the naive approach combined with his Arduino’s 10 bit ADC yielded resolution too poor to be worthwhile for his needs. But by using the right analog reference voltage and adjusting the voltage divider he could get a 20x improvement in resolution, down to 0.05°C in the relevant temperature range. This and more is the subject of the first post.

What comes next? Oversampling. Apparently fueled by a project featured on Hackaday back in 2015 [Edward] embarked on a journey to applying it to his thermistor problem. To quote [Edward] directly, to get “n extra bits of resolution, you need to read the ADC four to the power of n times”. Three bits gives about an order of magnitude better resolution. This effectively lets you resolve signals smaller than a single sample but only if there is some jitter in the signal you’re measuring. Reading the same analog line with no perturbation gives no benefit. The rest of the post deals with the process of artificially perturbing the signal, which turns out to be significantly complex, but the result is roughly 16 bit accuracy from a 10 bit ADC!

What’s the upside? High quality sensor readings from a few passives and a cheap Arduino. If that’s your jam check out this excellent series when designing your next sensing project!

By taking advantage of persistence in human vision, we can use modest bits of hardware to create an illusion of a far larger display. We’ve featured many POV projects here, but they are almost always an exploration in two dimensions. [Jamal-Ra-Davis] extends that into the third dimension with his Volumetric POV Display.

Having already built a 6x6x6 LED cube, [Jamal] wanted to make it bigger, but was not a fan of the amount of work it would take to grow the size of a three-dimensional array. To sidestep the exponential increase in effort required, he switched to using persistence of vision by spinning the slight source and thereby multiplying its effect.

The current version has six arms stacked vertically, each of which presents eight individually addressable APA102 LEDs. When spinning, those 48 LEDs create a 3D display with an effective resolution of 60x8x6.

We saw an earlier iteration of this project a little over a year ago at Bay Area Maker Faire 2018. (A demo video from that evening can be found below.) It was set aside for a while but has now returned to active development as an entry to Hackaday Prize 2019. [Jamal-Ra-Davis] would like to evolve his prototype into something that can be sold as a kit, and all information has been made public so others can build upon this work.

We’ve seen two-dimensional spinning POV LED display in a toy top, and we’ve also seen some POV projects taking steps into the third dimension. We like where this trend is going.

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Spending an hour or two around any consumer-level padlock or house deadbolt lock with a simple lockpicking kit will typically instil a good amount of panic and concern about security. While it’s true that any lock can be defeated, it’s almost comically easy to pick basic locks like this. So, if you’re looking for a level of security that can’t be defeated in two minutes with a tiny piece of metal, you might want to try something a little more advanced.

This project stemmed from an idea to use a YubiKey, a USB hardware token typically used for two-factor authentication, for physical locks instead. The prototype was built around an Arduino UNO, and all of the code and build instructions are available on the project’s site. The creator, [rprinz08], does not have one built inside of a secure enclosure so that would remain an exercise for the reader, but the proof-of-concept is interesting and certainly useful.

While digital keys like this can have their own set of problems (as all locks do), this would be a great solution for anyone needing to lock up anything where physical keys are a liability or a nuisance, where logging is important, or where many people need access to the same lock. The open source code and well-known platform make it easy for anyone to build, too.

As recently announced, the Arduino Certification Program : Arduino Fundamentals is a structured way for you to enhance and validate your Arduino skills. Although the exam has been available in the U.S. since May, we’re excited it to roll out to the EU and rest of the world (except Brazil).

Arduino Fundamentals provides you with the opportunity to gain official recognition for your knowledge in Arduino-related electronics, programming, and physical computing. If you pass the test, you will be rewarded with an Arduino Fundamentals certificate in your name containing a unique QR code to ensure authenticity. 

If you think you can answer 36 questions in 75 minutes, then you can become a fully certified member of the Arduino community and enhance your resume for just $30.

A free online demo is also available to help give you an idea of the types of queries you will be challenged with. Feeling confident in your Arduino abilities? Then what are you waiting for? Go ahead and give it a try!

Arduino Create, the integrated online platform that enables makers and professional developers to write code, access content, configure boards and share projects, now offers users the ability to upgrade their service by opting for the Create Maker plan to experience the Arduino IoT Cloud to the fullest.

Aside from no ad interruptions in their working space, for a monthly fee of $6.99 USD (plus applicable taxes), Create Maker plan subscribers will enjoy an array of extra features and benefits over the free Create plan.

Here’s a quick glimpse of what subscribers can look forward to:

• 250 sketches allowed in your sketchbook
• 200MB space to store sketches and libraries
• Unlimited compilation time to verify code and upload it to your board
• Five ‘things’ (connected objects) and 20 properties per each ‘thing’
• Access to set up and remotely control five of each cloud-enabled Arduino board type 
• Access to set up and remotely control three cloud-enabled Linux devices
• Access to set up and remotely control one cloud-enabled generic third-party board
• Custom library editing
• Web Editor support for third-party boards (ESP8266)
• Access to Arduino Create Chrome app

All of the above are in addition to the standard features that are available to all Arduino Create users, such as an always up-to-date online IDE and the option to tap into the power of the community on the Arduino Project Hub by browsing projects and making them their own. Users can sharetheir builds and receive feedback from others, while the in-depth guided flows make it easy to configure online services like the Web Editor and Cloud.

Ready to subscribe? If you’re fortunate enough to be one of the first 1,000 to do so, we’ll include a FREE MKR WiFi 1010 board with your monthly plan!