OAK-D Depth Sensing AI Camera Gets Smaller And Lighter

October 15, 2021 by Donald Papp 9 Comments

The OAK-D is an open-source, full-color depth sensing camera with embedded AI capabilities, and there is now a crowdfunding campaign for a newer, lighter version called the OAK-D Lite. The new model does everything the previous one could do, combining machine vision with stereo depth sensing and an ability to run highly complex image processing tasks all on-board, freeing the host from any of the overhead involved.

Animated face with small blue dots as 3D feature markers. — An example of real-time feature tracking, now in 3D thanks to integrated depth sensing.

The OAK-D Lite camera is actually several elements together in one package: a full-color 4K camera, two greyscale cameras for stereo depth sensing, and onboard AI machine vision processing with Intel’s Movidius Myriad X processor. Tying it all together is an open-source software platform called DepthAI that wraps the camera’s functions and capabilities together into a unified whole.

The goal is to give embedded systems access to human-like visual perception in real-time, which at its core means detecting things, and identifying where they are in physical space. It does this with a combination of traditional machine vision functions (like edge detection and perspective correction), depth sensing, and the ability to plug in pre-trained convolutional neural network (CNN) models for complex tasks like object classification, pose estimation, or hand tracking in real-time.

So how is it used? Practically speaking, the OAK-D Lite is a USB device intended to be plugged into a host (running any OS), and the team has put a lot of work into making it as easy as possible. With the help of a downloadable application, the hardware can be up and running with examples in about half a minute. Integrating the device into other projects or products can be done in Python with the help of the DepthAI SDK, which provides functionality with minimal coding and configuration (and for more advanced users, there is also a full API for low-level access). Since the vision processing is all done on-board, even a Raspberry Pi Zero can be used effectively as a host.

There’s one more thing that improves the ease-of-use situation, and that’s the fact that support for the OAK-D Lite (as well as the previous OAK-D) has been added to a software suite called the Cortic Edge Platform (CEP). CEP is a block-based visual coding system that runs on a Raspberry Pi, and is aimed at anyone who wants to rapidly prototype with AI tools in a primarily visual interface, providing yet another way to glue a project together.

Earlier this year we saw the OAK-D used in a system to visually identify weeds and estimate biomass in agriculture, and it’s exciting to see a new model being released. If you’re interested, the OAK-D Lite is available at a considerable discount during the Kickstarter campaign.

The Compute Module Comes Of Age: Say Hello To The Real Cutting Edge Of Raspberry Pi

October 14, 2021 by Jenny List 66 Comments

If we wanted to point to an epoch-making moment for our community, we’d take you back to February 29th, 2012. It was that day on which a small outfit in Cambridge put on the market the first batch of their new product. That outfit was what would become the Raspberry Pi Foundation, and the product was a run of 10,000 Chinese made versions of their very first single board computer, the Raspberry Pi Model B. With its BCM2835 SoC and 512 megabytes of memory it might not have been the first board that could run a Linux distribution from an SD card, but it was certainly the first that did so for pocket money prices. On that morning back in 2012 the unforseen demand for the new board brought down the websites of both the electronics distributors putting it on sale, and a now-legendary product was born. We’re now on version 4 of the Model B with specs upgraded in almost every sense, and something closer to the original can still be bought in the form of its svelte stablemate, the Pi Zero.

How Do You Evolve Without Casualties?

The original Pi Model B+ from 2014. The form factor has had a few minor changes, but hardware-wise the Pi 4 follows this pretty closely. Lucasbosch, CC BY-SA 3.0.

The problem with having spawned such a successful product line is this: with so many competitors and copies snapping at your heels, how do you improve upon it? It’s fair to say that sometimes its competitors have produced more capable hardware than the Pi of the moment, but they do so without the board from Cambridge’s ace in the hole: its uniquely well-supported Linux distribution, Raspberry Pi OS. It’s that combination of a powerful board and an operating system with the minimum of shocks and surprises that still makes the Pi the one to go for after all these years.

Continue reading “The Compute Module Comes Of Age: Say Hello To The Real Cutting Edge Of Raspberry Pi” →

Front view of vintage radio, with small screen inset into tuner.

Vintage Radio Gets Internet Upgrade

October 12, 2021 by Donald Papp 14 Comments

There’s nothing quite like vintage hardware, and the way it looks and works is something that can be worth celebrating. [Old Tech. New Spec] did that with his loving modification of a 1964 Dansette portable radio, bringing it into the modern era by giving it the ability to play Internet radio stations while keeping all the original controls and appearance. As he says, you’d hardly know it has been modified unless you turned it on.

Internet radio station logos scrolling across small LCD screen — A full color LCD behind a convex lens matches the radio’s aesthetic.

A real centerpiece of this conversion is that the inner part of the tuning dial has been replaced with a full color LCD display that shows, among other things, the logo of whatever Internet radio station is currently playing. The combination of LCD and convex lens looks fantastic, and blends beautifully into the aesthetic.

Inside the device is a Raspberry Pi, some simple Python scripts, and a Pirate Audio board. Together, they handle the job of audio streaming and output, displaying album art, and accepting inputs for playback controls. A large power bank ensures the result remains portable, and as usual with vintage hardware, there’s no worry about fitting everything inside. Watch it in action in the video embedded below. (And if the name of the audio board got you excited, but you’re disappointed to discover there’s no actual pirate broadcasting happening? Well, the Raspberry Pi can do that, too.)

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A French Minitel terminal becomes a Raspberry Pi-powered mini laptop.

Minitel Terminal Becomes Mini Laptop

October 8, 2021 by Kristina Panos 17 Comments

In 1980, France took a step into the future when the telecom companies introduced the Minitel system — a precursor to the Web where users could shop, buy train tickets, check stocks, and send and receive electronic mail through a small terminal. Minitel still had 10 million monthly connections in 2009, but the service was discontinued in 2012.

So, you can imagine how many Minitel terminals must be floating around at this point. [Gautchh] picked one up at a garage sale a while back and converted it into a battery-powered laptop for taking notes in class. Luckily for us, [Gautchh] recently open-sourced this project and has given us a wiring diagram, STLs, BOM, and a good look into the build process.

[Gautchh] started by gutting the Minitel, but saved the power button and the très chic power indicator that looks like a AA cell. The new 10.4″ LCD screen is held in place with four 3D-printed corner blocks and a bit of hot glue, and the original keyboard (which we’d love to clack on) is now wired up to an Arduino Pro Micro. The main brain — a Raspberry Pi 3B — is easily accessible through a handy little hatch in the back. Well, it looks like we’ve got a new ebay alert to set up.

In the mood for more AZERTY goodness? Check out this gallery of French computers, or a more traditional take on a Minitel with a Raspberry Pi.

Raspberry Pi Plots World Wide Earthquakes

October 5, 2021 by Dave Rowntree 9 Comments

What do you do when you stumble across a website posting real-time earthquake data? Well, if you’re [Craig Lindley] you write some code to format it nicely onto a display, put it in a box, and watch it whilst making dinner.

[Craig] started off with coding in Forth on the ESP32, using ESP32Forth, but admits it didn’t go so well, ditching the ESP32 for a Raspberry Pi 3 he had lying around, and after a brief detour via C++, he settled on a Python implementation using Pygame.

A case was 3D printed, which he says worked OK, but needs a little tuning to be perfect. There is no shortage of casing options for the Pi with the official 7″ display, [Craig] suggests that it probably wasn’t worth the effort to 3D print the case and if he was building it again would likely use a commercially available option which had a better fit.

When developing the code, and watching it work, he noted clusters of earthquakes around Hawaii, then he found out Kilauea had just gone up. Wow.

For a similar take, check out this other recent build using an ESP32 and the same data source.

CO2 laser cutting ceramic sheet under water film

Water Is The Secret Ingredient When Laser Cutting Ceramics To Make Circuits

October 2, 2021 by Dave Rowntree 21 Comments

[Ben Krasnow] over at Applied Science was experimenting with cutting inexpensive ceramic sheets with his cheap CO2 laser cutter when he found that (just as expected) the thermal shock of the CO2 beam would cause cracking and breaking of the workpiece. After much experimentation, he stumbled upon a simple solution: submersion under a thin layer of water was sufficient to remove excess heat, keeping thermal shock at bay, and eventually cutting the material. Some prior art was uncovered, which we believe is this PHD thesis (PDF) from Manchester University in the UK. This is a great read for anyone wanting to dig into this technique a little deeper.

The CO2 laser cutter is a very versatile tool, capable of cutting and etching a wide range of materials, many of natural origin, such as cardboard, leather and wood, as well as certain plastics and other synthetic materials. But, there are also materials that are generally a no-go, such as metals, ceramics and anything that does not absorb the laser wavelength adequately or is too reflective, so having another string in one’s bow is a good thing. After all, not everyone has access to a fibre laser.

After dispensing with the problem of how to cut ceramic, it got even more interesting. He proceeded to deposit conductive traces sufficiently robust to solder to. A mask was made from vinyl sheet and a squeegee used to deposit a thick layer of silver and glass particles 1 um or less in size. This was then sintered in a small kiln, which was controlled with a Raspberry Pi running PicoReFlow, and after a little bit of scrubbing, the surface resistance was a very usable 2 mΩ/square. Holes cut with the laser, together with some silver material being pushed through with the squeegee formed through holes with no additional effort. That’s pretty neat!

Some solder paste and parts were added to the demo board, and with an added flare for no real reason other than he could, reflowed by simply applying power direct to the board. A heater trace had been applied to the bottom surface, rendering the board capable of self-reflowing. Now that is cool!

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Super 8 Camera Brought Back To Life

September 30, 2021 by Bryan Cockfield 32 Comments

The Super 8 camera, while a groundbreaking video recorder in its time, is borderline unusable now. Even if you can get film for it (and afford its often enormous price), it still only records on 8mm film which isn’t exactly the best quality of film around, not to mention that a good percentage of these cameras couldn’t even record audio. They were largely made obsolete by camcorders in the late ’80s and early ’90s, although some are still used for niche artistic purposes. If you’d rather not foot the bill for the film, though, you can still put one of these to work with the help of a Raspberry Pi.

[befinitiv] has a knack for repurposing antique analog equipment like this while preserving its aesthetic. While the bulk of the space inside of this camera would normally be used for housing film, this makes a perfect spot to place a Raspberry Pi Zero, a rechargeable battery, and a power converter circuit all in a 3D printed enclosure that snaps into the camera just as a film roll would have. It uses the Pi camera module but still makes use of the camera’s built in optics which include a zoom function. [befinitiv] also incorporated the original record button so that from the outside this looks like a completely unmodified Super 8 camera.

The camera can connect to a WiFi network and can stream live video to a computer, or it can record video files to an internal SD card. As a bonus, thanks to the power converter circuit, it is also capable of charging a cell phone. [befinitiv] notes that many of the aesthetic properties of 8 mm film seem to be preserved when using this method, and he has several theories as to why but no definitive answer. If you’d like to take a look at some of his other projects like this, check out this analog camera that is now able to take digital pictures. Continue reading “Super 8 Camera Brought Back To Life” →