Bunnie’s Betrusted Makes First Appearance As Mobile, FPGA-Based SoC Development Kit

September 29, 2020 by Maya Posch 18 Comments

Recently, [Bunnie Huang] announced his Precursor project: a spiffy-looking case housing a PCB with two FPGAs, a display, battery and integrated keyboard. For those who have seen [bunnie]’s talk at 36C3 last year, the photos may look very familiar, as it is essentially the same hardware as the ‘Betrusted’ project is intended to use. This also explains the name, with this development kit being a ‘precursor’ to the Betrusted product.

In short, it’s a maximally open, verifiable, and trustworthy device. Even the processor is instantiated on an FPGA so you know what’s going on inside the silicon.

He has set up a Crowd Supply page for the Precursor project, which provides more details. The board features a Xilinx Spartan 7 (XC7S50) and Lattice iCE40UP5K FPGA, 16 MB SRAM, 128 MB Flash, integrated WiFi (Silicon Labs WF200-based), a physical keyboard and 1100 mAh Lio-Ion battery. The display is a 200 ppi monochrome 336 x 536 px unit, with both the display and keyboard backlit.

At this point [bunnie] is still looking at how much interest there will be for Precursor if a campaign goes live. Regardless of whether one has any interest in the anti-tamper and security features, depending on the price it might be a nice, integrated platform to tinker with.

The Screwdriver You Don’t Need, But Probably Want

September 4, 2020 by Danie Conradie 50 Comments

Screwdrivers are simple devices with a simple purpose, and there is generally little fanfare involved with buying yourself a new set. We’ve never seen one marketed as an object of desire, but we have to admit that [Giaco] managed to do precisely that. He created the Kinetic Driver, a ~~fidget spinner~~ precision screwdriver designed to use its rotational momentum to loosen and tighten screws.

The main difference between the Kinetic Driver and other screwdrivers is a big brass mass at the front end for high rotational inertia and a high-quality ceramic bearing at the back end for minimal drag. It uses 4 mm precision bits, so its utility will be limited to small screws, which makes it perfect for working on small electronics.

[Giaco] says the idea came after running a successful Kickstarter campaign for a utility knife, where he found that his favorite screwdriver for the many small screws was one with a fat metal body which allowed it to spin easily. In the video after the break, he gives an excellent insight into the development process. He started by creating a series of 3D printed prototypes to figure out the basic shape, before making the first metal prototype. [Giaco] also shows the importance of figuring out the order of operation for machining, which is often glossed over in other machining videos. Be sure to check out the beautiful launch video at 17:52. Continue reading “The Screwdriver You Don’t Need, But Probably Want” →

Vizy The AI Camera Aims To Ease Machine Vision

August 17, 2020 by Donald Papp 17 Comments

Cameras are getting smarter and more capable than ever, able to run embedded machine vision algorithms and pull off tricks far beyond what something like a serial camera and microcontroller board would be capable of, and the upcoming Vizy aims to be even smarter and easier to use yet. Vizy is the work of Charmed Labs, and this isn’t their first foray into accessible machine vision. Charmed Labs are the same folks behind the Pixy and Pixy 2 cameras. Vizy’s main goal is to make object detection and classification easy, with thoughtful hardware features and a browser-based interface.

Vizy can identify common birds with “Birdfeeder”, one of the several built-in applications that uses local processing only.

The usual way to do machine vision is to get a USB camera and run something like OpenCV on a desktop machine to handle the processing. But Vizy leverages a Raspberry Pi 4 to provide a tightly-integrated unit in a small package with a variety of ready-to-run applications. For example, the “Birdfeeder” application comes ready to take snapshots of and identify common species of bird, while also identifying party-crashers like squirrels.

The demonstration video on their page shows off using the built-in high-current I/O header to control a sprinkler, repelling non-bird intruders with a splash of water while uploading pictures and video clips. The hardware design also looks well thought out; not only is there a safe shutdown and low-power mode for the Raspberry Pi-based hardware, but the lens can be swapped and the camera unit itself even contains an electrically-switched IR filter.

Vizy has a Kickstarter campaign planned, but like many others, Charmed Labs is still adjusting to the changes the COVID-19 pandemic has brought. You can sign up to be notified when Vizy launches; we know we’ll be keen for a closer look once it does. Easier machine vision is always a good thing, because it helps free people to focus on clever ideas like machine vision-based tool alignment.

Open-Source 2 GHz Oscilloscope Probe

May 7, 2020 by Ted Yapo 8 Comments

If you do any work with high-speed signals, you quickly realize that probing is an art unto itself. Just having a fast oscilloscope isn’t enough; you’ve got to have probes fast enough to handle the signals you want to see. In this realm, just any old probe won’t do: the input capacitance of the classic RC probe you so often see on low-bandwidth scopes starts to severely load down a circuit well below 1 GHz. That’s why we were really pleased to see [Andrew Zonenberg’s] new open-source design for a 2 GHz resistive probe hit Kickstarter.

The design of this new probe looks deceptively simple. Known as a Z₀-probe, transmission-line probe, or resistive probe, the circuit works as a voltage divider, created from the 50-Ohm input impedance of a high-speed oscilloscope input and an external resistor, to reduce loading on the circuit-under-test. In this case, the input resistance has been chosen to be 500 Ohms, yielding a 10x probe. In theory, building such a probe is as simple as soldering a resistor to the end of a piece of coaxial cable. You can do exactly that, but in practice, optimizing a design is much more complex. As you can see in the schematic, just choosing a resistor of the right value doesn’t cut it at these frequencies. Even the tiny 0402-size resistors have parasitic capacitance and inductance that affect the response, and choosing a combination of parts that add to the correct resistance but reduce the overall capacitive loading makes a huge difference.

Don’t be fooled: the relatively simple schematic belies the complexity of such a design. At these speeds, the PCB layout is just as much of a component as the resistors themselves, and getting the transmission-line and especially the SMA footprint launch correct is no easy task. Using a combination of modeling with the Sonnet EM simulator and empirical testing, [Andrew] has ended up with a design that’s flat (+/- 1 dB) out to 1.98 GHz, with a 10-90% rise time of 161 ps. That’s a fast probe.

The probe comes in a few options, from fully assembled with traceable specs to a DIY solder-it-yourself version. You probably know which of these options you need.

We really like to see this kind of knowledge and thoroughness go into a project, and we’d love to see the Kickstarter project reach its goals, but perhaps the best part is that the design is permissively open-source licensed. This is a case where having the board layout open-sourced is key; the schematic tells you maybe half of what’s really going on in the circuit, and getting the PCB right yourself can be a long and frustrating exercise. So, have a look at the project, and if you haven’t got probes suitable for your fastest scopes, build one, or better yet, support the development of this exciting design.

We’ve seen [Andrew’s] oscilloscope work before, like glscopeclient, his remote oscilloscope utility program.

Failed: Air Umbrella

January 25, 2020 by Al Williams 43 Comments

About five years ago, a Kickstarter popped up for the air umbrella. It wasn’t long before the project fell apart and the company made at least some refunds. Old news, we know. But [The Action Lab] recently explored the physics behind the air umbrella and why it wouldn’t be very practical. (Video, embedded below.)

Notice we said not very practical, not unworkable. It is possible to shoot rain away from you by using pressurized air. The problem is you need a lot of air pressure. That means you also need a lot of battery. In particular, [The Action Lab] used a leaf blower and even with that velocity, there was only minimal water deflection. In other words, you are still going to get wet.

Continue reading “Failed: Air Umbrella” →

Tales (and Advice) From Setting Up A Product Line

January 2, 2020 by Donald Papp 5 Comments

Making something that has to get into others’ hands involves solving a lot of different problems, many of which have nothing at all to do with actually building the dang things. [Conor Patrick] encountered them when he ran a successful Kickstarter campaign for an open-source USB security key that was not only shipped to backers, but also made available as an ongoing product for sale. There was a lot of manual and tedious work that could have been avoided, and so [Conor] laid out all the things he wishes he had done when first setting up a product line.

Turning these unprogrammed boards into finished products then shipping them is a big job.

If the whole process is a river, then the more “upstream” an issue is, the bigger its potential impact on everything that comes afterwards. One example is the product itself: the simplest and most easily managed product line is one that has only one product with no variations. That not only minimizes errors but makes supply, production, and shipping more straightforward. Striving for a minimum number of products and variations is also an example of something [Conor] didn’t do. In their crowdfunding campaign they offered the SoloKeys USB device — an implementation of the FIDO2 authentication token — as either USB-A or USB-C. There were also two types of key: NFC-capable (for tapping to a smartphone) and USB only. That is four products so far.

Offering keys in an unlocked state for those who want to tamper makes it eight different products. On top of that, they offered color choices which not only adds complexity to production, but also makes it harder to keep track of what everyone ordered. [Conor] also observed that the Kickstarter platform and back end are really not set up like a store, and it is clunky at best to try to offer (and manage) different products and variations from within it.

Another major point is fulfillment and in [Conor]’s opinion, unless the quantities are small, an order fulfillment company is worth partnering with. He says there are a lot of such companies out there, and it can be very time consuming to find the right one, but it will be nothing compared to the time and effort needed to handle, package, address, and ship several hundreds (or thousands!) of orders personally. His team did their own fulfillment for a total of over 2000 units, and found it a long and tedious process filled with hidden costs and challenges.

There’s good advice and background in [Conor]’s writeup, and this isn’t his first rodeo. He also shared his thoughts on taking electronics from design to production and the more general advice remains the same for it all: be honest and be open. Under-promise and over-deliver, especially when it comes to time estimates.

ATX2AT Makes Retrocomputing Safer, Heads To Kickstarter

November 25, 2019 by Donald Papp 21 Comments

It’s easy to take power supplies for granted in modern computing, but powering vintage hardware is not always so simple or worry-free. The power supplies for old electronics are themselves vintage, and the hardware being powered can be quite precious. A power problem can easily cause fried components and burned traces on a board. As [Doc TB] observes, by the time you hear crackling, it’s already far too late.

To address this, [Doc TB] designed the ATX2AT Smart Converter as an open source project and recently decided to make it available through a Kickstarter campaign. ATX2AT is a way to safely and securely replace some vintage power supplies with a standard PC ATX power supply, and adds a large number of protection features such as current monitoring and programmable reaction time for overcurrent protection. All of this can help prevent a retrocomputer enthusiast’s precious vintage hardware from being damaged in the event of a problem. It’s not just for powering known-good hardware; it can be invaluable when testing or repairing hardware that might be in an unknown state.

When we first came across [Doc TB]’s ATX2AT project we recognized it as a well-made device to address a specific niche, and to do it well. Assessing risk takes into account not only the probability of a problem occurring, but also just how bad things would be if it did happen. If your old hardware is precious enough to warrant the extra protection, or you are into repairing or assessing old hardware, then an ATX2AT might be just what you need. You can see it in action in the video embedded below.

Continue reading “ATX2AT Makes Retrocomputing Safer, Heads To Kickstarter” →