Vacuum fluorescent displays (VFDs) have a distinct cool blue-greenish glow, and were once used in a wide range of devices, from VCRs to microwave ovens and even car dashboards. Although extremely popular way back when, they can be more difficult to source today. In the video below, Scotty Allen of the Strange Parts YouTube channel takes on the challenge of getting a $600 ISE (now Noritake) display up and running with an Arduino Due.

The process starts with examining the datasheet to find that the Due’s 3.3V logic can indeed drive the 20×2 character display, then he constructs a custom adapter board to do just that. After more datasheet lurking, head scratching and hacking, he finally got it to show “Hello world!” toward the end of the clip, along with some simple animations. 

The VFD control is part of a larger build that will be revealed in the future, and a good reminder of just how much trial and error is needed to succeed in making something awesome.

If you fly drones for fun—or perhaps even for work—you know that piloting them can sometimes be a difficult tasks. Imagine, however, trying to control four drones simultaneously. While also “challenging,” researchers at the Skolkovo Institute of Science and Technology in Russia have come up with a new approach for commanding such a swarm using only arm movements.

SwarmTouch takes the form of a wrist and finger-mounted device, with an array of eight cameras tracking its position. When the operator moves their arm, the drones react to the hand motion and the other flying robots in the group, as if there was a mechanical system linking each one together. 

Feedback is provided by an Arduino Uno connected to the control station via an XBee radio, which tells the operator whether the swarm is expanding or contracting using vibration motors on a wearer’s fingertips. The setup is on display in the video below and its research paper can be found here.

We propose a novel interaction strategy for a human-swarm communication when a human operator guides a formation of quadrotors with impedance control and receives vibrotactile feedback. The presented approach takes into account the human hand velocity and changes the formation shape and dynamics accordingly using impedance interlinks simulated between quadrotors, which helps to achieve a life-like swarm behavior. Experimental results with Crazyflie 2.0 quadrotor platform validate the proposed control algorithm. The tactile patterns representing dynamics of the swarm (extension or contraction) are proposed. The user feels the state of the swarm at his fingertips and receives valuable information to improve the controllability of the complex life-like formation. The user study revealed the patterns with high recognition rates. Subjects stated that tactile sensation improves the ability to guide the drone formation and makes the human-swarm communication much more interactive. The proposed technology can potentially have a strong impact on the human- swarm interaction, providing a new level of intuitiveness and immersion into the swarm navigation.

Drowning is the third leading cause of accidental death in New Zealand, and the vast majority of lifeguard rescues are due to rip currents—hard to observe unless you’re already in peril. In order to help fix this problem, Victoria University of Wellington students Hannah Tilsley and Chamonix Stuart designed the “Nah Yeah Buoy” water safety system.

The system consists of a network of sensing buoys and a mobile app. The buoys feature a water flow sensor on their base to measure currents, and use an Arduino to control lights on the top to shine according to the water speed. Green means it’s safe to swim, yellow is for caution, and red indicates danger, in similar manner to how traffic lights. Additionally, two-way wireless communication sends alerts to lifeguards on the shore, who can override the lights to warn of danger when needed. 

As seen here, the project was named a runner-up in the 2019 New Zealand James Dyson Award.

The “Nah Yeah Buoy” is an adaptive system for water safety designed to identify rip currents near beaches, visualise their locations and movements, and provide interactive alerts and warnings for lifeguards and water users.

Our “Nah Yeah buoy” consists of a network of sensing buoys and a mobile app for lifeguards. Rip currents are characterised by a localised strong flow of water that moves away from the shore at a typical speed of 0.5 to 2.5 meters per second. Each buoy of the network has a customised fluid flow sensor at its bottom to measure the strength/speed of the water as it flows through, and the value is compared to a set of thresholds by a built-in microcontroller real time. A high-intensity light placed on top then indicates the level of danger in three colours: green for “Yeah” (good to swim); orange for an alert; and red for “Nah” (do not swim). The buoys also transmit the information wirelessly to an app on the lifeguards’ mobile devices which allows them to adjust the thresholds as needed. The buoys are lightweight, very easy to install and individually manageable and form a network automatically.

Joop Brokking has been experimenting with a miniature candle-powered steam engine. It’s an amazing little device, able to push a piston over and over to turn a flywheel, releasing the steam via a mechanically-controlled valve. But just how fast does it go?

Of course, there are a plethora of ways to determine its speed, but Brokking chose to do so using an Arduino Uno, a potentiometer and an LED that’s arranged over the piston assembly. 

The light source is programmed to pulse on and off, with a frequency that can be adjusted using the potentiometer. He then aligned this pulsing with the piston’s cyclic rate, visually “freezing” the device in time. This frequency and RPM numbers are output over the serial monitor, giving him a speed of around 1850 RPM.

While the “M” in MIDI stands for “musical”, it’s possible to use this standard for other things as well. [s-ol] has been working on a VJ setup (mixing video instead of music) using various potentiometer-based hardware and MIDI to interface everything together. After becoming frustrated with drift in the potentiometers, he set out to outfit the entire rig with custom-built encoders.

[s-ol] designed the rotary-encoder based boards around an FPGA. It monitors the encoder for changes, controls eight RGB LEDs per knob, and even does capacitive touch sensing on the aluminum knob itself. The FPGA communicates via SPI with an Arduino master controller which communicates to a PC using a serial interface. This is [s-ol]’s first time diving into an FPGA project and it looks like he hit it out of the park!.

Even if you’re not mixing video or music, these encoders might be useful to any project where a standard analog potentiometer isn’t accurate or precise enough, or if you just need something that can dial into a specific value quickly. Potentiometers fall short in many different ways, but if you don’t want to replace them you might modify potentiometers to suit your purposes.

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.

YouTuber Oracid1 has developed a unique family of four-legged robots, dubbed “FiveBarQuads.”

The quadrupeds all feature ultrasonic sensing for navigation and a body made out of LEGO components — and as seen in the first video below, his latest (and largest) version is able to navigate quite nicely on its own. It’s even able to traverse a grate and maneuver around a potted plant, though chair legs are understandably a bit tricky.

The robots use an Arduino Uno for control along with a total of 16 micro servos in its shoulders (four each) in order to move the limbs. Two servos are employed to actuate each upper linkage for the legs, which are attached to bottom sections, and finally to the feet portion through a series of joints. This allows for an interesting locomotion capability that could be applicable in a variety of situations.

Non-profits can do great work, and in order to help others visualize the needs they serve and what they are doing, Jason Wolin came up with an amazing map for his organization.

The massive map stretches down 14 feet of a brick wall, with the continents cut out of MDF, and a pair of accompanying LCD TVs that show data about different areas.

Three computers are used for control, two of which are used to play videos on each screen. The third handles overhead map lighting controlled via the DMX protocol to illuminate the map in various configurations. Each of the PCs are coordinated using a trio of Arduino Nanos, allowing video and lighting effects to be displayed in perfect sync.

Richard of ARITH-MATIC had the idea to build a 4-bit computer based on 7400 series ICs (like the 74HC273, 74HC193, and 74HC125), but other responsibilities got in the way of this becoming a reality for quite some time. Finally, with the Retro Computer Festival at the Centre for Computing History in Cambridge, England held earlier this month, he went ahead and started the project in hopes of creating a working computer in under 30 days.

The resulting homebrew CPU is known as the ‘Cambridge-1,’ comprised mostly of 7400 series ICs, wiring, and an SRAM chip for storage carefully arranged on a set of breadboards. In addition to the other components, an Arduino Micro is also implemented. While not technically a retro device, the Arduino allowed him to “change the control logic on-the fly,” and gave him the flexibility to finish the project in his compressed time scale.

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.