A home-made vacuum pickup tool

Hackaday Prize 2022: Salvaged Pumps And Hoses Make A Neat Vacuum Pickup Tool

Anyone who’s ever assembled a PCB full of tiny SMD parts will have found that tweezers are not always the best tool when it comes to accurate positioning. Thin, flat components like microcontrollers can be awkward to pick up securely, while small resistors and capacitors have a tendency of snapping out of your tweezers’ grip and flying off into the sunset (or your carpet). Vacuum pickup tools can be a great help, but the most convenient models, with an electric air pump and a foot switch, can be a bit expensive. [sjm4306] shows that it doesn’t have to be that way: he built his “VacPen” mostly from reused components.

At the heart of the project is a little vacuum pump with a pen-like device hooked up to it through a flexible hose. The tip of the pen holds a pickup nozzle that came from a cheap manual pick and place tool. Both the pump and pen were salvaged from some gas analysis instrument that [sjm4306] tore apart a long time ago; the pen is especially convenient since it comes with a built-in brush-like filter that can trap any debris or tiny parts that might be accidentally swallowed.

The VacPen controller is housed inside a neat 3D printed enclosure that holds a custom PCB with an ATtiny microcontroller. The pump can be operated either through a foot switch, or by pressing on the touch-sensitive pad on top of the enclosure. [sjm4306] made this by soldering a wire to a copper penny and sticking it on the inside of the lid: simple, effective and cheap.

As you can see in the video embedded below, the VacPen is perfectly capable of picking up any kind of SMD component, and just as importantly, immediately releasing it at the desired moment. If you’re new to SMD technology, we can recommend this tutorial by [Bil Herd] that covers vacuum tweezers as well. If you’re more into automating vacuum pickup tools, this cool robot might be of your interest.

Continue reading “Hackaday Prize 2022: Salvaged Pumps And Hoses Make A Neat Vacuum Pickup Tool”

Can You Help NASA Build A Mars Sim In VR?

No matter your project or field of endeavor, simulation is a useful tool for finding out what you don’t know. In many cases, problems or issues aren’t obvious until you try and do something. Where doing that thing is expensive or difficult, a simulation can be a low-stakes way to find out some problems without huge costs or undue risks.

Going to Mars is about as difficult and expensive as it gets. Thus, it’s unsurprising that NASA relies on simulations in planning its missions to the Red Planet. Now, the space agency is working to create a Mars sim in VR for training and assessment purposes. The best part is that you can help!

Continue reading “Can You Help NASA Build A Mars Sim In VR?”

How The Roland 808 Cowbell Worked

Every generation has an instrument which defines its sound, and for those whose formative musical years lie in the 1980s, a very strong contender to the crown is the Roland TR-808 percussion synthesizer. Its sounds can be recognized across a slew of hits from that era and every decade since, and though the original instrument wasn’t a commercial success it remains accessible through sample packs, emulations, and clones. The 808 was an all-analogue device that didn’t use samples, thus [Mark Longstaff-Tyrrell] has been able to reproduce its distinctive cowbell sound with reference to some of the original circuitry.

It shouldn’t come as too much of a surprise to find that the circuit is refreshingly simple. The trigger pulse is converted into an envelope which controls a pair of oscillators. The mixed output passes through a bandpass filter to create the distinctive sound on the output which you can hear in the video below the break. The circuit is recreated on a breadboard with the only concession to modernity being a microcontroller taking the place of the Schmitt trigger oscillators in the original.

Altogether it provides a fascinating insight into the synthesis behind a classic sound, and gives us an increased appreciation for the design skills of those Roland engineers who created it. We’ve looked at the 808 before a few times, including an explanation of the famous faulty transistors which contributed to its sound.

Continue reading “How The Roland 808 Cowbell Worked”

With Rocket Lab’s Daring Midair Catch, Reusable Rockets Go Mainstream

We’ve all marveled at the videos of SpaceX rockets returning to their point of origin and landing on their spindly deployable legs, looking for all the world like something pulled from a 1950s science fiction film.  On countless occasions founder Elon Musk and president Gwynne Shotwell have extolled the virtues of reusable rockets, such as lower operating cost and the higher reliability that comes with each booster having a flight heritage. At this point, even NASA feels confident enough to fly their missions and astronauts on reused SpaceX hardware.

Even so, SpaceX’s reusability program has remained an outlier, as all other launch providers have stayed the course and continue to offer only expendable booster rockets. Competitors such as United Launch Alliance and Blue Origin have teased varying degrees of reusability for their future vehicles, but to date have nothing to show for it beyond some flashy computer-generated imagery. All the while SpaceX continues to streamline their process, reducing turnaround time and refurbishment costs with each successful reuse of a Falcon 9 booster.

But that changed earlier this month, when a helicopter successfully caught one of Rocket Lab’s Electron boosters in midair as it fell back down to Earth under a parachute. While calling the two companies outright competitors might be a stretch given the relative sizes and capabilities of their boosters, SpaceX finally has a sparing partner when it comes to the science of reusability. The Falcon 9 has already smashed the Space Shuttle’s record turnaround time, but perhaps Rocket Lab will be the first to achieve Elon Musk’s stated goal of re-flying a rocket within 24 hours of its recovery.

Continue reading “With Rocket Lab’s Daring Midair Catch, Reusable Rockets Go Mainstream”

Section from the ESP8266 datasheet, showing maximum input voltage as 3.6V, but not mentioning ESD diodes to VCC and only talking about a snap-back circuit set to 6V.

Is ESP8266 5 V Tolerant? This Curve Tracer Says Yes!

Some people state that ESP8266 is tolerant of 5 V logic levels on its GPIOs, while others vehemently disagree, pointing at the datasheet-stated 3.6 V maximum. Datasheets aren’t source code for compiling the chip, however, and aren’t universally correct and complete either. [Avian] decided to dig deeper into the claims, conduct an experiment with an actual ESP8266 chip, then share the results for all of us.

For the experiment, he used a curve tracer – a device capable of producing a wide range of voltages and measuring the current being consumed, then plotting the voltage-to-current relationship. This helps characterize all sorts of variables, from diode breakdown voltages to transistor characteristics. The curve tracer he uses is a capable and professional-looking DIY build of his, and arguably, deserves a separate write-up!

The reasoning behind [Avian]’s experiment is simple – if the pin, set to an input, starts consuming a higher amount of current at a certain voltage threshold, then there’s gotta be some chip-internal structure, intended or unintended, that would be damaged at this voltage. Curve tracer in hand, he set up an ESP-01 module to set a GPIO to input, and started increasing the voltage.

A curve tracer output graph, showing that there's no noticeable increase of current consumed across the range of 0V to 6.6V - current increasing from 0.2mA to 0.4mA in that range

The tests have shown that, while there’s a reverse biased ESD diode from GPIO pins to ground, there don’t seem to be diodes from the GPIO pin to the VCC rail – and those are the primary concern for 5 V tolerance. There does seem to be something functionally akin to a 6 V Zener diode internally, which should clamp the voltage before it gets too way high for the chip to handle. None of that should be a problem for 5 V compatibility, and it seems fair to interpret this as a confirmation of 5 V tolerance until someone shows otherwise.

[Avian] didn’t want to destroy an ESP8266, so the experiment was conducted with a 1 K series resistor between the curve tracer and the input – which might have biased the results a bit. On the other hand, adding series resistors in front of your inputs is an overall underappreciated practice, 5 V or otherwise. He also points out that, while the pins don’t seem to be adversely impacted by the higher input voltage, the bootloader might set some of them to 3.3 V outputs on boot-up, shorting your 5 V source to your 3.3 V rail — worth keeping in mind!

[Avian]’s research journeys are fun to follow, and we recommend you check his blog out; last time, we covered his research of an innocent-looking 3.5 mm jack hiding a devious audio compensation circuit. Since we first covered the ESP8266 in 2014, we’ve been researching all the things it’s really capable of, and we brought up the topic of GPIO 5 V compatibility way back in 2016 – it’s reassuring to finally put this question to rest!

We thank [Adrian] for sharing this with us!

Making A Concrete Pinhole Camera

A pinhole camera is a simple device that can be built out of virtually any simple closed chamber, and is a great way to learn about the basic principles of photography. [amuu] has created a version that can be readily made out of concrete, of all materials!

The photos captured by the camera featured some artifacts from light leaks and grit, but the results are enjoyable for their lo-fi, homebrew aesthetic!

The build starts with the creation of a mold for the concrete, using laminated sheets of foam. The foam is assembled with cut-up pieces of a ballpoint pen serving as cores in the mold. This provides a space for the film winders in the final product. The concrete is then mixed and poured into the mold, and allowed to set. Tapping or vibrating the mold is key to getting all the air bubbles out of the mixture.

Once set, the foam is mechanically removed from the concrete and the camera can be finished off. The internals are given a lick of black paint to improve the camera’s light-tightness. The shutter, pinhole, and film winder are then also fitted to allow the camera to function.

[amuu]’s first attempt to take photos with the camera lead to some results that were pleasingly lo-fi. There are overscan issues on the film and some other artifacts, but overall, the results are esoteric and fun. If you’re not a fan of the concrete camera, though, you can always consider making a 3D-printed pinhole camera instead!

Pitch Sequencer Turns Tascam Tape Deck Into Instrument

The cool thing about magnetic tape is that by varying the speed at which you play it back, you can vary the pitch of the output. [Issac] decided to take advantage of this, executing a fancy digitally-controlled pitch mod on his Tascam Porta 02 tape deck.

The build uses a Raspberry Pi Pico, which employs PWM to control the speed of the tape drive’s motor. This is achieved with the use of an NPN transistor driven by the PWM output of the Pico. This allows accurate control of motor speed, and thus pitch.

With that sorted out, the project was fleshed out with an OLED screen and a rotary encoder. These allow various patches or scripts to be run on the Pico, controlling the motor speed of the tape player in various ways. With a bit of work, [Issac] was also able to create a function that converted MIDI note values into PWM values that determine various motor speeds.

The natural thing to do next was to put in a tape with a looping sample at a set pitch, and then vary it in a sequence controlled by the Pico. The 8 steps of the sequence can be manually set with the rotary control, and in future, [Issac] even plans to add a real MIDI input, allowing the system to act as a monophonic synth.

If you prefer other routes to pitch shifting shenanigans, check out this project. Video after the break.

Continue reading “Pitch Sequencer Turns Tascam Tape Deck Into Instrument”