There’s not a huge amount of detail available in the video below, and no build log per se. But [Electron Dust] has a few shots in the video that explain what’s going on, as well as a brief description in a reddit thread about the device. The idea is to spin a ball up to a steady speed and release it the same way every time. The rig itself is made of wood and spun by plain brushed DC motors – [Electron Dust] explains that he chose them over PWM servos to simplify things and eliminate uncertainty in the release point. The ball is retained by a pair of arms, each controlled by a pair of hobby servos. An Arduino spins along with everything else and counts 50 revolutions before triggering the servos to retract and release the ball. A glass positioned at the landing spot captures the ball perfectly once everything is dialed in.
Though Python 3 was released in 2008, many projects are still stuck on Python 2.
It’s understandable that porting large existing codebases to a new version is a prospect which sends a shiver down many a developer’s spine. But code inevitably needs to be maintained, and so when all the shiny new features that would fix everything are in a new version, is it really worth staying rooted in the past?
We’ll take you through some of the features that Python 2 programs are missing out on, not only from 3.0 but up to the current release (3.7).
Used for general purpose programming, data science, website backends, GUIs, and pretty much everything else; the first programming language for many, and claimed to be the fastest growing in the world, is of course Python. The newest version 3.7.0 has just recently been released.
Naturally any release of Python, no matter how small, undergoes meticulous planning and design before any development is started at all. In fact, you can read the PEP (Python Enhancement Proposal) for Python 3.7, which was created back in 2016.
What’s new in 3.7? Why should you upgrade? Is there anything new that’s actually useful? I’ll answer these questions for you by walking through some examples of the new features. Whilst there’s not much in this release that will make a difference to the Python beginner, there’s plenty of small changes for seasoned coders and a few headline features you’ll want to know about.
What’s an ADSR envelope generator? If you are a big music hacker, you probably know. If you are like the rest of us, you might need to read [Mich’s] post to find out that it is an attack-decay-sustain-release (ADSR) envelope generator. Still confused? It is a circuit used in music synthesis. You can see a demo of the device in the video below.
Before the Altair–which was sort of the first hobbyist computer you could actually buy–electronics magazines were full of music synthesizer projects that had a lot in common with the analog computers of old. A lot of people took that very seriously and then computers took over the collective consciousness and we found musical hackers started working with (digital) computer-based synthesizers. But the old analog synth designs just won’t die. [Mich’s] ADSR is based on an ancient design, and the amount of information and additions he provides makes it worth a read, even if you don’t fancy building one.
We’ve been watching the development of the ESP32 chip for the last year, but honestly we’ve been a little bit cautious to throw all of our friendly ESP8266s away just yet. Earlier this month, Espressif released version 2.0 of their IoT Development Framework (ESP-IDF), and if you haven’t been following along, you’ve missed a lot.
We last took a serious look at the IDF when the chips were brand-new, and the framework was still taking its first baby steps. There was no support for such niceties as I2C and such at the time, but you could get both cores up and running and the thing connected to the network. We wanted to test out the power-save modes, but that wasn’t implemented yet either. In short, we were watching the construction of a firmware skyscraper from day one, and only the foundation had been poured.
But what a difference eight months make! Look through the GitHub changes log for the release, and it’s a totally new ballgame. Not only are their drivers for I2C, I2S, SPI, the DAC and ADCs, etc, but there are working examples and documentation for all of the above. Naturally, there are a ton of bugfixes as well, especially in the complex WiFi and Bluetooth Low Energy stacks. There’s still work left to do, naturally, but Espressif seems to think that the framework is now mature enough that they’ve opened up their security bug bounty program on the chip. Time to get hacking!
Depending on your opinion of these little critters, that could be a good thing or a bad thing. We don’t deny that mice are cute as all get-out, but when they do damage to foodstuffs that you’ve put an entire summer’s effort into growing, harvesting and preserving, cute isn’t worth much.
Our preference for taking care of rodent problems is either bioremediation or rapid cervical dislocation, but if you’re more of the catch-and-release type, this trap is for you. It’s just a 2-liter soda bottle on a wire pivot and mounted to a scrap wood frame; when the offending critter unwisely enters the neck of the bottle, its weight flips the bottle down and blocks the exit. Release is as simple as removing the bottle from the frame and letting Monsieur Jingles wiggle free. The questions of where to release and how many times you’ll keep catching the same mouse are left as an exercise for the reader.
Remember – a live catch trap is only humane if it’s checked regularly. To that end, maybe something like das Katzetelegraf could be added to this trap.
I’m writing a series of articles on resin casting as an extension to my experiences with the instructions found in the wonderful Guerrilla Guide. However, mistakes were made. Having run out of my usual mold release I went to a back-up jar that was lying around from a casting project long, long ago in a workshop far, far away.
I’m refining a technique of making a mold the quick and dirty way. Everything was going well, the sprues looked good and the master released from the silicone. It was time to do the second half of the mold. As usual I applied a generous amount of mold release. Since it was the first time this mold was to be used I went ahead and did all the proper steps. Rubbing off the dried release and applying a few more coats just to be sure.
I was completely unaware that I was applying mold release designed for urethane molds only. In other words I thoroughly covered my silicone mold in silicone bonding agents. I remained unaware until trying to separate the halves of the mold and found them thoroughly joined. After going through the stages of grief I finally figured out where it all went wrong.
Oh well. I’m ordering some of my regular pick, Stoner A324, and that should do the trick. There’s also Mann- Ease Release 200. While having probably the best name a release agent can have, it doesn’t work as well and needs approximately 100 years to dry. After this setback I’d rather just, grudgingly, learn my lesson and order the correct thing.
So now that we know the right way to fix this is to order the right product, is there a hack to get around it? Does anyone have a homebrew trick for release agent that can be used in a pinch? Leave your comments below.