Back in the late 1970s, comedian Steve Martin had a bit about “Let’s get small!” Over on Hackaday.io, [Daniel Grießhaber], has taken that call to heart. He’s been working on DIL-Duino, a minuscule form factor Arduino in an 8-pin DIP format.

Built with an ATtiny85, the board has an area of just under 75 square millimeters (less than 8 mm x 10 mm). If you add the USB port, it still comes in at just over 144 square millimeters. [Daniel] found other small Arduino boards like the Olimexino-85s and the Nanite are not as small as his design.

The module has a QFN CPU and castellated holes around the perimeter for mounting. With pin headers, this would easily fit into a breadboard (as [Daniel] shows) or you could mount it directly to another board like a surface mount device. In fact, that’s the reason for using castellated holes: you can inspect that the solder joint at the mating SMD pad is good. You sometimes hear the technique called half-vias or leadless chip carrier.

If you note, [Daniel] used an oversized board with full holes around the perimeter and then had the board maker score the board, so the holes are cut in half. This is a better technique than trying to drill half holes on the board edge, which is difficult to do.

Naturally, this isn’t the first tiny Arduino we’ve seen. If you are an ARM fan, there’s some little bitty cards for it, too, although not quite as small as DIL-Duino.

How do you make a robot hand? If you are [Robimek], you start with some plastic spiral tubing, some servo motors, and some fishing line. Oh, and you also need an old glove.

The spiral tubing (or pipe, if you prefer) is cut in a hand-like shape and fused together with adhesive. The knuckle joints are cut out to allow the tubing to flex at that point. The fishing line connects the fingertips to the servo motors.

The project uses an Arduino to drive the servos, although you could do the job with any microcontroller. Winding up the fishing line contracts the associated finger. Reeling it out lets the springy plastic pipe pull back to its original position.The glove covers the pipes and adds a realistic look to the hand.

Granted, this is probably more practical as a display piece than a working hand. We’d like to put it in our next Halloween project. We’ve seen some simple hand builds before, but the glove is a nice touch. For some reason, many of our robot hand projects like to make rude gestures. You can see a video of [Robimek]’s hand working below.

How do you make a robot hand? If you are [Robimek], you start with some plastic spiral tubing, some servo motors, and some fishing line. Oh, and you also need an old glove.

The spiral tubing (or pipe, if you prefer) is cut in a hand-like shape and fused together with adhesive. The knuckle joints are cut out to allow the tubing to flex at that point. The fishing line connects the fingertips to the servo motors.

The project uses an Arduino to drive the servos, although you could do the job with any microcontroller. Winding up the fishing line contracts the associated finger. Reeling it out lets the springy plastic pipe pull back to its original position.The glove covers the pipes and adds a realistic look to the hand.

Granted, this is probably more practical as a display piece than a working hand. We’d like to put it in our next Halloween project. We’ve seen some simple hand builds before, but the glove is a nice touch. For some reason, many of our robot hand projects like to make rude gestures. You can see a video of [Robimek]’s hand working below.

There’s an old saying that the nice thing about standards is there are so many of them. For digital voice modes, hams have choices of D-Star, DMR, System Fusion, and others. An open source project, the Multimode Digital Voice Modem (MMDVM), allows you to use multiple modes with one set of hardware.

There are some kits available, but [flo_0_] couldn’t wait for his order to arrive. So he built his own version without using a PCB. Since it is a relatively complex circuit for perf board, [flo_0_] used Blackboard to plan the build before heating up a soldering iron. You can see the MMDVM in action below.

The build includes an Arduino, of course, and the neat perf board wiring makes for a good-looking project. We’ve covered digital voice that uses PCs before and even some digital ham modes that use an Arduino. Or check out the MMDVM project for more info.

The traditional theremin is more or less an audio oscillator with two metal rods. Using proximity sensing, one rod controls the pitch of the oscillator and the other controls the volume. [Teodor Costachiou] apparently asked himself the excellent question: Why does the proximity sensor have to use capacitance? The result is an Arduino-based theremin that uses IR sensors to determine hand position.

[Teodor] used a particular type of Arduino–the Flip and Click–because he wanted to use Click boards for the IR sensors and also to generate sound via an MP3 board based around a VS1053. The trick is that the VS1053 has a realtime MIDI mode, and that’s how this Theremin makes it tones.

Of course, a real theremin is distinctly analog. A tiny change in hand position creates a small change in the output. With digital sensors and sound generation, the output is more in discrete steps, but according to [Teodor], the effect isn’t bad. We were hoping for a video (or, at least, an audio clip) but [Teodor] pleaded that he’s not a musician. He did include a video of a real theremin performance with his post, and you can see it below. But that’s a real analog theremin.

If you want to build something more traditional, have a look at Open Theremin. Or, if you want to get your exercise, how about trying a terpsitone. If you do, and can play the theme to The Day the Earth Stood Still, we’d love to see the video. Meanwhile, if you didn’t know the theremin had an espionage connection, you haven’t been staying current on Hackaday posts.

This was gonna happen – sooner or later. [matthewhallberg] built a “Smart” trash can that is connected to the Internet and can be controlled by its own Android App. We’re not sure if the world needs it, but he wanted one and so built it. He started it out on a serious note, but quickly realized the fun part of this build – check out his funny Infomercial style video after the break.

The build itself is uncomplicated and can be replicated with ease. A servo motor helps flip the lid open and close. This is triggered by an ultrasonic ping sensor, which responds when someone waves a hand in front of the trash can. A second ping sensor helps inform the user when it is full and needs to be emptied. A Leonardo with the Idunio Yun shield helps connect the trash can to the internet. An mp3 shield connected to a set of powered computer speakers adds voice capability to the trash can, allowing it to play back pre-recorded sound clips. Finally, a Bluetooth module lets him connect it to an Android phone and the companion app controls the trash can remotely.

For the IoT side of things, [matthewhallberg] uses a Temboo account to send an email to the user when the trash can is full. The Arduino sketch, a header file to configure the Temboo account, and the Android application can all be downloaded from his blog. If this project inspires you, try building this awesome Robotic trash can which catches anything that you throw near it  or read the barcodes off the trash being thrown out and update the grocery list.

[Neumi] has built a CNC Laser using CD-ROM drives as the X and Y motion platforms. The small 405nm laser can engrave light materials like wood and foam. The coolest use demonstrated in the video is exposing pre-coated photo-resist PCBs.

With $61 US Dollars (55 Euro) for the Arduino, stepper drivers, and a laser in the project, [Nuemi] got a pretty capable machine after adding a few parts from the junk bin. He wanted to avoid using existing software in order to learn the concepts behind a laser engraver. In the end, he has a working software package which can send raster scans to an Arduino mega. The mega then controls the sync between the stepper and laser firings. The code is available on GitHub.

The machine can do a 30x30mm PCB in 10 minutes. It’s not about to set a record, but it’s cool and not at all bad for the price. You can see the failed PCBs lined up in the video from the initial tuning, but the final one produced a board very equivalent to the toner transfer method. Video after the break.

Bicycle riders can never be too visible: the more visible you are, the less chance there is someone will hit you. That’s the idea behind the Arduibag, a neat open-source project from [Michaël D’Auria] and [Stéphane De Graeve]. The project combines a joystick that mounts on the handlebars with a dot matrix LED display in a backpack. By moving the joystick, the user can indicate things such as that they are turning, stopping, say thank you or show a hazard triangle to warn of an accident.

The whole project is built from simple components, such as an Adafruit LED matrix and a Bluno (an Arduino-compatible board with built-in Bluetooth 4.0) combined with a big battery that drives the LED matrix. This connects to the joystick, which is in a 3D printed case that clips onto the handlebars for easy use. It looks like a fairly simple build, with the larger components being mounted on a board that fits into the backpack and holds everything in place. You then add a clear plastic cover to part of the backpack over the LED matrix, and you are ready to hit the road, hopefully without actually hitting the road.

Like any good project, [Michaël] and [Stéphane] aren’t finished with it yet: they are also looking for ways to improve it. In particular, they want to reduce the number of batteries, as there is currently a large battery that drives the display and another smaller one that drives the Arduino.

App development is not fun for everyone, and sometimes you just want to control a device from your phone with minimal work. Blynk appears to be a fairly put-together library for not only hooking up any Arduino or esp8266 to a phone through WiFi, but also through the net if desired.

Install the app onto your iPhone or Android device. Install the libraries on your computer. Next, modify your Arduino source to either pass direct control of a pin to Blynk, or connect Blynk to a virtual pin inside your code for more advanced control. If you want to go the easy route, create an account, log into the app, and drag and drop the interface you’d like. If the idea of letting some corporation host your Arduino project sends shivers down your spine, there is also an option to host your own server. (Editorial snark: Yes, it requires a server. That’s the cost of “simplicity”.)

There have been a few times where we’ve wished we could add app control to our projects, but installing all the libraries and learning a new language just to see a button on a screen didn’t seem worth it. This is a great solution. Have any of you had experience using it?

The World War II German Enigma encoding machine is something of an icon in engineering circles not just for its mechanical ingenuity but for the work of the wartime staff at Bletchley Park in decoding its messages. Without it we would not have had Colossus, the first programmable digital electronic computer, and subsequent technological developments might have taken a slower pace towards what we take for granted today.

Sadly for the Enigma enthusiast though, real machines are now few and far between. Our grandparents’ generation saw to that through the chaos and bombing of the fight across Europe. If you want to handle one you will have to either have an outrageous amount of money, work for a museum, or maybe for the GCHQ archivist.

This has not stopped our community building Enigma replicas, and the latest one to come to our attention here at Hackaday shows some promise. [lpaseen]’s meinEnigma is an electronic Enigma driven by an Arduino Nano, with rotary encoders to represent the Enigma rotors and multi-segment alphanumeric displays standing in for the lighted letters in the original. It supports all the different variations of rotors from the original in software, has a physical plugboard, and a serial port over USB through which all machine functions can be controlled. The machine as it stands is a fully working prototype, the plan is that a final machine will resemble the original as closely as possible.

All the code used in the project can be found on GitHub, along with [lpaseen]’s Arduino library for the Holtek HT16K33 keyboard/display chip used to handle those tasks.

We’ve featured a few Enigma machines on Hackaday over the years. One was built into a wristwatch, another into a hacked child’s toy, but the closest in aim to [lpaseen]’s offering is this rather attractive replica also driven by an Arduino. It is also worth mentioning that should your travels ever take you to Buckinghamshire you can visit the Bletchley Park Museum and neighboring  National Museum of Computing, to get the Enigma and Colossus story from the source.