Do Bounties Hurt FOSS?

September 27, 2023 by 17 Comments

As with many things in life, motivation is everything. This also applies to the development of software, which is a field that has become immensely important over the past decades. Within a commercial context, the motivation  to write software is primarily financial, in that a company’s products are developed by individuals who are being financially compensated for their time. This is often different with Free and Open Source Software (FOSS) projects, where the motivation to develop the software is in many cases derived more out of passion and sometimes a wildly successful hobby rather than any financial incentives.

Yet what if financial incentives are added by those who have a vested interest in seeing certain features added or changed in a FOSS project? While with a commercial project it’s clear (or should be) that the paying customers are the ones whose needs are to be met, with a volunteer-based FOSS project the addition of financial incentives make for a much more fuzzy system. This is where FOSS projects like the Zig programming language have put down their foot, calling FOSS bounties ‘damaging’.

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Passive Components Get Better

September 27, 2023 by 40 Comments

When you want to talk about cool new components, you are probably thinking about chips or, these days, even modules. Passive components like resistors, capacitors, and inductors are a solved problem, right? [Darshill Patel] begs to differ. There is still innovation happening in the passive market, and he highlights some of the recent advances.

There are thick-film resistors that don’t need lead, for example. There are also supercapacitor modules with very low ESR. For inductors, at least one manufacturer is moving away from traditional wire loops and using flat wire windings instead. These have a larger cross-section, which reduces unwanted resistance. In addition, it offers more cooling area for heat dissipation.

Of course, passive components have never been as simple as people think. Picking a capacitor’s value is only half the battle. You also need to consider the material to optimize how it works in your design. Wirewound resistors are also inductors unless you get special non-inductive ones that use special wiring techniques to cancel much of the parasitic inductance.

It shows that you can never stop learning about even the simplest components. We are still waiting to figure out what we want to do with a memristor. While tiny surface mount components are good for some assembly reasons, they also have helped reduce unwanted component effects.

Will Nickel-Hydrogen Cells Be The Energy Storage Holy Grail?

September 27, 2023 by 38 Comments

You may have heard us here remarking in the past, that if we had a pound, dollar, or Euro for every miracle battery technology story we heard that was going to change the world, we would surely be very wealthy by now. It’s certainly been the case that many such pronouncements refer to promising chemistries that turn out only to be realizable in a lab, but here there’s news of one with a bit of pedigree. Nickel hydrogen batteries have a long history of use in space, and there’s a startup producing them now for use on the ground. Could they deliver the energy storage Holy Grail?

The cathode in a nickel-hydrogen battery is formed by nickel hydroxide, and the anode is formed of hydrogen. If a gas as an anode sounds far fetched, we’re guessing that their structure is similar to the zinc-air battery, in which zinc hydroxide forms in a paste of powdered zinc, and works against oxygen from the air over a porous conductive support. What gives them their exciting potential is their ability to take more than 30,000 charge/discharge cycles, and their relative safety when compared to lithium ion cells. Hydrogen in a pressure vessel might not seem the safest of things to have around, but the chemistry is such that as the pressure increases it reacts to form water. The cost of the whole thing is reduced further as new catalysts have replaced the platinum used by NASA on spacecraft.

We really hope that these batteries will be a success, but as always we’ll wait and see before calling it. They may well be competing by then with the next generation of zinc-air cells.

Dead E. Ruxpin Appears Alive And Well

September 26, 2023 by 12 Comments

What are you doing to scare trick-or-treaters this Halloween? Surely something, right? Well, Hackaday alum [CameronCoward] certainly has his holiday under control with Dead E. Ruxpin, a murderous, cassette tape-controlled animatronic bear.

Readers of a certain vintage will no doubt see the correlation to Teddy Ruxpin, an animatronic bear from the 1980s whose mouth moved as it read stories from cassette tapes. Cleverly, the engineers used one stereo channel for the story’s audio, and the other channel to control the bear’s mouth.

Dead E. Ruxpin takes this idea and expands it, using the same two channels to send audio and control three servo motors that move both arms and the mouth. How is this possible? By sending tones built from one or more frequencies.

Essentially, [Cameron] assigned a frequency to each movement: mouth open/closed, and left and/or right arm up or down. These are all, of course, synced up with specific points in the audio so Dead E. doesn’t just move randomly, he dances along with the music.

The bear is actually a hand puppet, which leaves room for a 3D-printed skeleton that holds the RP2040 and the servos and of course, moves the puppet’s parts. We can’t decide if we prefer the bulging bloodshot eyes, or think the cutesy original eyes would have made a scarier bear. Anyway, check out the build/demo video after the break to see it in action.

Are you now into Teddy Ruxpin? Here’s a bit more about those scare bears. And don’t forget, Halloween Hackfest runs now until October 31st.

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Beating Apple’s Secret Lid Angle Sensor Calibration With Custom Tool

September 26, 2023 by 35 Comments

Among the changes made by Apple to its laptops over the years, the transition from a Hall sensor-based sleep sensor to an angle sensor that determines when the lid is closed is a decidedly unpopular one. The reason for this is the need to calibrate this sensor after replacement, using a tool that Apple decided to keep for itself. That is, until recently [Stephan Steins] created a tool which he creatively called the ‘nerd.tool.1‘. This widget can perform this calibration procedure with the press of its two buttons, as demonstrated on [Louis Rossmann]’s YouTube channel.

This new angle sensor was first introduced in late 2019, with Apple’s official reason being an increased level of ‘precision’. As each sensor has to be calibrated correctly in order to measure the magnetic field and determine the associated lid angle, this means that third-party repair shops and determined MacBook owners have to transplant the chip containing the calibration data to a replacement sensor system. Until now, that is. Although the nerd.tool.1 is somewhat pricey at €169 ($179 USD), for a third-party MacBook repair shop this would seem to be a steal.

It is however unfortunate that Apple persists in such anti-repair methods, with recently [Hugh Jeffreys] also calling Apple out on this during a MacBook Pro M1/M2 teardown video. During this teardown [Hugh] came across this angle sensor issue by swapping parts between two otherwise identical MacBook Pros, indicating just how annoying this need to calibrate one tiny lid angle sensor is.

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Feed Your Fasteners In Line, With A Bowl Feeder

September 26, 2023 by 30 Comments

If you spend much time around industrial processes, you may have seen a vibrating bowl feeder at work. It’s a clever but simple machine that takes an unruly pile of screws or nuts and bolts, and delivers them in a line the correct way up. They do this by shaking the pile of fasteners in a specific way — a spiral motion which encourages them to work to the edge of the pile and align themselves on a spiral track which leads to a dispenser. It’s a machine [Fraens] has made from 3D printed parts, and as he explains in the video below the break, there’s more to this than meets the eye.

The basic form of the machine has a weighted base and an upper bowl on three angled springs. Between the two is an electromagnet, which provides the force for the vibration. The electromagnet needed to be driven with a sine wave which he makes with an Arduino and delivers as PWM via an H-bridge, but the meat of this project comes in balancing the force and frequency with the stiffness of the springs. He shows us the enormous pile of test prints made before the final result was achieved, and it’s a testament to the amount of work put into this project. The final sequence of a variety of objects making the march round the spiral is pure theatre, but we can see his evident satisfaction in a job well done.

Oddly this isn’t the first bowl feeder we’ve seen, though it may be one of the most accomplished. We particularly like this tiny example for SMD parts.

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$13 Scope And Logic Analyzer Hits 18 Msps

September 26, 2023 by 31 Comments

We aren’t sure what’s coolest about [Richard Testardi’s] Flea-Scope. It costs about $13 plus the cost of making the PCB. It operates at 18 million samples per second. It also doesn’t need any software — you connect to it with your browser! It works as an oscilloscope, a logic analyzer, and a waveform generator. Not bad. The board is basically a little life support around a PIC32MK and the software required to run it.

Of course, for $13, you need to temper your expectations. One analog input reads from -6 to 6V (hint: use a 10X probe). The goal was for the instrument to be accurate within 2%.  There are also nine digital inputs sampled simultaneously with the analog sampling. The signal generator portion can output a 4 MHz square wave or a 40 kHz arbitrary waveform.

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