This Is Not A Laptop, It’s A KVM Combo

August 19, 2024 by Donald Papp 67 Comments

A spare monitor and keyboard are handy things to have around, but they’re a bit of a hassle. They are useful for hardware development, plugging in to headless servers, or firing up a Raspberry Pi or similar single-board computer (SBC). If that’s something you do and portability and storage space are important to you, then you may be interested in the CrowView Note.

I got an opportunity to test and provide feedback on an early version of this unusual device, which is functionally a portable spare monitor plus keyboard (and touchpad) without the bulk and extra cables. Heck, it’s even giving me ideas as the guts of a Cyberdeck build. Let’s take a look.

What It Is

It really looks like a laptop, but it’s actually a 14″ 1920 x 1280 monitor and USB keyboard in a laptop form factor.

There is also an integrated trackpad, speakers and mic, and a rechargeable battery. That makes it capable of providing its own power, and it can even function as a power bank in a pinch. There’s an HDMI input on one side, and on the other is a full-featured USB-C port that accepts video input via the DisplayPort altmode.

Pictured here is a Raspberry Pi 5 with optional PCB adapter to eliminate cables. The three ports (HDMI in, USB-C 5 V out, and USB-A for peripherals) provide all the board needs.

The CrowView Note is a pretty useful device for a workbench where one is often plugging hardware in for development or testing, because there’s no need to manage a separate monitor, keyboard, and mouse.

It is not a laptop, but attaching an SBC like a Raspberry Pi makes it act like one. The three ports conveniently located on the left-hand side (HDMI in, USB-C out for power to the SBC, and USB-A in for peripherals like keyboard and trackpad) are all that are needed in this case. Elecrow offers a “cable eliminator” PCB adapters to make the process of connecting a Raspberry Pi 5 or a Jetson Nano as simple as possible. The result is something that looks and works just like a laptop.

Well, almost. The SBC will still be a separate piece of hardware, whether connected by cables or by one of Elecrow’s PCB adapters. The result is OK for bench work, but especially in the case of the PCB adapter, not particularly rugged. Still, it’s a nice option and makes working on such boards convenient and cable-free.

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Meta Doesn’t Allow Camera Access On VR Headsets, So Here’s A Workaround

August 18, 2024 by Donald Papp 13 Comments

The cameras at the front of Meta’s Quest VR headsets are off-limits to developers, but developer [Michael Gschwandtner] created a workaround (Linkedin post) and shared implementation details with a VR news site.

The view isn’t a pure camera feed (it includes virtual and UI elements) but it’s a clever workaround.

The demo shows object detection via MobileNet V2, which we’ve seen used for machine vision on embedded systems like the Raspberry Pi. In this case it is running locally on the VR headset, automatically identifying objects even though the app cannot directly access the front-facing cameras to see what’s in front of it.

The workaround is conceptually simple, and leverages the headset’s ability to cast its video feed over Wi-Fi to other devices. This feature is normally used for people to share and spectate VR gameplay.

First, [Gschwandtner]’s app sets up passthrough video, which means that the camera feed from the front of the headset is used as background in VR, creating a mixed-reality environment. Then the app essentially spawns itself a Chromium browser, and casts its video feed to itself. It is this video that is used to — in a roundabout way — access what the cameras see.

The resulting view isn’t really direct from the cameras, it’s akin to snapshotting a through-the-headset view which means it contains virtual elements like the UI. Still, with passthrough turned on it is a pretty clever workaround that is contained entirely on-device.

Meta is hesitant to give developers direct access to camera views on their VR headset, and while John Carmack (former Meta consulting CTO) thinks it’s worth opening up and can be done safely, it’s not there yet.

Lunar Lander Game Asks You To Write A Simple Autopilot

August 16, 2024 by Donald Papp 28 Comments

Everyone likes a good lunar landing simulator, and [Dominic Doty] wrote a fun take on the idea: your goal is to write an autopilot controller to manage the landing. Try it out!

Virtual landers are far cheaper than real ones, thank goodness.

[Dominic] was inspired in part by this simple rocket landing game which is very much an exercise in reflex and intuition, not to mention being much faster-paced than the classic 1979 video game (which you can also play in your browser here.)

[Dominic]’s version has a similar classic look to the original, but embraces a more thoughtful approach. In it, one uses plain JavaScript to try to minimize the lander’s angle, velocity, and angular velocity in order to land safely on the generated terrain.

Want to see if you have the right stuff? Here’s a direct link to Lunar Pilot. Don’t get discouraged if you don’t succeed right away, though. Moon landings have had plenty of failures, and are actually very hard.

Robust Speech-to-Text, Running Locally On Quest VR Headset

August 16, 2024 by Donald Papp 3 Comments

[saurabhchalke] recently released whisper.unity, a Unity package that implements whisper locally on the Meta Quest 3 VR headset, bringing nearly real-time transcription of natural speech to the device in an easy-to-use way.

Whisper is a robust and free open source neural network capable of quickly recognizing and transcribing multilingual natural speech with nearly-human level accuracy, and this package implements it entirely on-device, meaning it runs locally and doesn’t interact with any remote service.

It used to be that voice input for projects was a tricky business with iffy results and a strong reliance on speaker training and wake-words, but that’s no longer the case. Reliable and nearly real-time speech recognition is something that’s easily within the average hacker’s reach nowadays.

We covered Whisper getting a plain C/C++ implementation which opened the door to running on a variety of platforms and devices. [Macoron] turned whisper.cpp into a Unity binding which served as inspiration for this project, in which [saurabhchalke] turned it into a Quest 3 package. So if you are doing any VR projects in Unity and want reliable speech input with a side order of easy translation, it’s never been simpler.

Liquid (Reversibly) Solidifies At Room Temperature, Gets Used For 3D Prints

August 9, 2024 by Donald Papp 8 Comments

Researchers demonstrate sustainable 3D printing by using poly(N-isopropylacrylamide) solutions (PNIPAM), which speedily and reliably turn solid by undergoing a rapid phase change when in a salt solution.

This property has been used to 3D print objects by using a syringe tip as if it were a nozzle in a filament-based printer. As long as the liquid is being printed into contact with a salt solution, the result is a polymer that solidifies upon leaving the syringe.

What’s also interesting is that the process by which the PNIPAM-based solutions solidify is entirely reversible. Researchers demonstrate printing, breaking down, then re-printing, which is an awfully neat trick. Finally, by mixing different additives in with PNIPAM, one can obtain different properties in the final product. For example, researchers demonstrate making conductive prints by adding carbon nanotubes.

While we’ve seen the concept of printing with liquids by extruding them into a gel bath or similar approach, we haven’t seen a process that prides itself on being so reversible before. The research paper with all the details is available here, so check it out for all the details.

Forget Ship In A Bottle, How About Joule Thief In A Fuse Tube?

August 7, 2024 by Donald Papp 14 Comments

We love close-up pictures of intricate work, and [w] hits the spot with a tiny joule thief in a fuse case (social media post, embedded below) powered by an old coin cell from a watch. It’s so tiny!

Ethernet transformers contain tiny coils.

A joule thief is a sort of minimum-component voltage booster that can suck nearly every last drop of energy from even seemingly-drained batteries, and is probably most famously used to light LEDs from cells that are considered “dead”.

Many joule thief designs feature hand-wound coils, which is great for junk box builds but certainly becomes more of a challenge for a tiny build like this one.

We really like that [w] salvaged a miniscule coil from an Ethernet transformer, most of which look like blocky SMD components from the outside but actually contain tiny coils.

The joule thief has been the basis of plenty of hacks over the years, and it’s always nice to see new twists on the concept.

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Proof That find + mkdir Are Turing-Complete

August 5, 2024 by Donald Papp 10 Comments

Data manipulation is at the heart of computation, and a system is said to be Turing-complete if it can be configured to manipulate data in a way that makes implementing arbitrary computation possible. [Keigo Oka] shared a proof that find and mkdir together are Turing-complete, which is to say, a system with only GNU’s find and mkdir has access to enough functionality to satisfy the requirements of Turing completeness, which ignores questions of efficiency or speed.

[Keigo Oka]’s first attempt at a proof worked to implement Rule 110, an elementary cellular automata configuration that has been shown to be Turing-complete, or ‘universal’, but has been updated to implement a tag system as it’s proof, and you can see it in action for yourself.

Seeing basic utilities leveraged in such a way illustrates how computation is all around us, and not always in expected places. We’ve also seen Turing-complete origami and computation in cellular automata.