Keep In Touch With Grandma, With This Lo-Tech Interface

We have so many options through which to communicate with our friends and relatives during the lockdown, thanks to our smartphones and the number of apps that serve all possible needs. Impressive as they are though, a smartphone is not suitable for everyone. In particular older people can find them less easy to use, and the consequent loss of communication ability is addressed by [Manu] with the Yayagram, described in a thread of Spanish-language Tweets and later the thread was translated into English.

On the top of the box is a microphone with push-to-talk switch, a small thermal printer, and a set of 1/4″ jack sockets with associated jump lead. Each socket corresponds to a relative, and an audio message to that relative can be posted via Telegram simply by speaking into the microphone with the button pressed. Replies are then printed through the thermal printer. Meanwhile behind the scenes is a Raspberry Pi holding it all together.

We like the simplicity of the interface, and who wouldn’t want to ensure that their older relatives were able to keep in touch! But while the jump lead is a neat touch, we hope it’s not too difficult for extremely frail hands. It’s certainly not the first accessibility project for older people that we’ve seen.

Small Open Source Vehicle Hacking Platform

[Florian] and his engineering team at Munich-based bmc::labs has developed a clever set of prototyping boards for vehicle hacking and rapid product development, collectively called the bmc::board or bmc::mini. These stackable development boards were initially designed for in-house use. The team took a general purpose approach to the design so the boards could be used across a wide range of projects, and they should be useful to anyone in the field. [Florian] decided to release the boards to the community as open-source and certified by OSHWA (Open Source Hardware Association).

There are four boards currently defined, with several more in the works:

  • mini::base — Main microcontroller board, STM32F103-based
  • mini::out — I/O board with CAN bus, JTAG, etc.
  • mini:: grid — RF board providing GPS and GSM capability
  • mini::pit — local wireless connectivity, WiFi and Bluetooth, and 2nd CAN bus

At 54 x 42.5 mm, these boards are pretty small; a form-factor they describe as “exactly half a credit card”. We like the Wurth WR-MM family of stacking connectors they are using, and the symmetrical pinout means you can rotate the cards as needed. But at first glance, these thru-hole connectors seem to limit the stack to just two boards, although maybe they plan move to an SMT flavor of the connector in future designs permitting taller stacks.

If you’re into vehicle electronics and/or vehicle hacking, definitely take a look at these. You can check out [Florian]’s bmc::board Hackaday.io project page and the team’s GitHub repository for more details. Here’s another project by team member [Sebastian] using one of the future bmc::bike modules to eavesdrop on ECU communications, where he sensibly advises the reader “First, pull over and get off the bike. Never hack a two-wheeled vehicle while riding it!”.

No discussion of vehicle CAN bus tools should omit the work of Craig Smith, who literally wrote the book on hacking your car, and whose talk along with Hackaday’s own Eric Evenchick of CANtact fame we covered back in 2016. [Florian] has started a CrowdSupply campaign where you can see some more details of this project and a short promotional video.

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Hackaday Links: April 25, 2021

There’s much news from the Jezero Crater on Mars this week, and all of it was good. Not only did the Ingenuity helicopter make history by making the first powered, controlled flight of an aircraft on another planet, it made a second longer, more complex flight just a couple of days later. This time, the autonomous rotorwing craft flew to a higher altitude than the maiden flight, hovered for a bit longer, and made a lateral move before landing safely again on the surface. Three more flights of increasing complexity (and risk) are scheduled over the next two weeks, with the next set to happen early Sunday morning. I have to admit that even though the Ingenuity tech demonstration seemed a little like a publicity stunt when I first heard about it, especially when compared to the Perseverance’s main mission of searching for evidence of life on Mars, the Ingenuity team’s successes have made a believer out of me.

Speaking of technology demonstrations, NASA fired up the MOXIE experiment aboard Perseverance for the first time. Intended to explore the possibility of producing oxygen from the thin carbon dioxide-rich Martian atmosphere, the Mars Oxygen In-Situ Resource Utilization Experiment made about 5.4 grams of oxygen total at a rate of about 6 grams an hour. We detailed the technology MOXIE uses, called solid-oxide electrolysis, which depends on a scandium-stabilized zirconium oxide ceramic electrolyte to strip the oxygen from superheated carbon dioxide using an electric current. Should the technology prove itself over the planned total of ten MOXIE runs over the next few months, a scaled up version of the device could someday land on Mars and produce the estimated 55 metric tons of oxygen needed to fuel a return trip from a crewed mission.

By now we’ve all heard about the global semiconductor shortage, or perhaps felt the pinch ourselves while trying to procure parts for a build. It’s easy to count the crunch as yet another follow-on from the COVID-19 shutdowns and the logistics woes the pandemic begat, so one might have hope that with lockdowns easing up around the world, the shortage will soon be over as manufacturers ramp up production. But not so fast — it looks like the machines needed to make the chips are the latest victims of the shortage. According to Nikkei Asia, wire bonding machines, wafer dicers, and laser drilling machines are all in short supply, with orders for new machines booked out for a year. Like toilet paper this time last year, chip makers are hoarding machines, ordering 50 or 100 of them at a time, in the hopes of having enough to meet production goals. And when machines are available, travel restrictions are making it difficult to get on-site installation and support from factory reps. The bottom line — this isn’t over yet, not by a long shot.

We all know the Stack Overflow memes, and few of us who are being honest haven’t squirmed a bit when thinking about just how screwed we’d be without being able to copy a bit of code to get us past that rough part in a project. But just how often do people copy code from Stack Overflow? Quite a lot, actually, if SO’s analysis of the use of copy commands on their pages is to be believed. For two weeks, SO monitored the number of times the Ctrl-C (or Command-C, if that’s your jam) key combination was pressed. They toted up over 40 million copies, most often from the answers to questions and almost always from the code blocks within them. We suppose none of this is exactly unexpected — memes are memes for a reason, after all — but what we found surprising is that one in four visitors to Stack Overflow copied something within five minutes of loading a page. Being charitable, we’d say the speed with which coders accept someone else’s work is an indication that maybe they were almost at an answer themselves and just needed a little reminder. On the other hand, it could be a sign of separation driving them to get something working.

And finally, while we know we’ve recommended videos from Grady at Practical Engineering recently, we couldn’t help but plug another of his videos as a must-watch. This time, Grady tackles the Suez Canal blockage, and he presents it in the same dispassionate, informed way that he previously handled the engineering roots of the Texas blackouts. If you think the Ever Given grounding was just a case of poor seamanship, think again — Grady makes a compelling case for possible hydrodynamic causes of the incident, including “squatting” and the bank effect. He also speculates on the geotechnical forces that held the ship fast, in the process of which he helpfully introduces the concept of dilatancy and how it explains the way your feet seem to “dry out” a zone around them as you walk across the beach.

Continue reading “Hackaday Links: April 25, 2021”

Arduino MKR Makes Nespresso Monitoring Easy

Monitoring an appliance with a microcontroller usually follows a well-worn path of diving inside and finding somewhere in the electrical circuitry that can be connected through some kind of interface to a microcontroller. For his Nespresso pod coffee machine, [Steadman] eschewed tearing into the device, and instead chose to monitor the sound it makes. A commodity sound threshold sensor board is hooked up to an Arduino MKR Zero, and this set-up logs coffee consumption. It’s important to note how this generation of Arduino is no longer one of the simple boards of old, instead it sports an RTC and SD card alongside its SAMD21 Cortex-M0+ processor so it is perfect for just such a datalogging project. The coffee data can be saved into a CSV file viewable by a spreadsheet, for which code is provided.

We like this project for its non-invasive simplicity, and we can see that there could be plenty of other similar machines that could benefit from an analagous technique for non-invasive monitoring. While the pages of Hackaday are full of coffee machine projects we see surprisingly few pod coffeemakers, perhaps because our readers are a canny bunch who balk at paying a premium for their caffeine. If you do happen to have a Nespresso machine though, perhaps you’d like some help identifying the capsules.

An ESP32 Development Board For Sailors

[Matti Airas] wanted to have a better electronics platform for making his boat smarter, more connected, and safer. He found traditional marine electronics expensive and not suited for hacking and tinkering. There was also the issue of lack of interoperability between device generations from the same supplier and between different brands. This led him to design the Sailor Hat with ESP32 — a marine specific, open source hardware development board.

Applications include all kinds of sensor and control interfaces for the boat, such as measurement of fuel or water level, engine RPM, anchoring chain length counter, or setting up smart lighting or smart refrigeration control. The board is designed to work with the traditional NMEA 2000 standard, as well as with Signal K. NMEA 2000 is standardized as IEC 61162-3, but isn’t open source or free. Signal K, on the other hand, is free and open source, and can co-exist alongside NMEA 2000.

The marine environment can be pretty harsh with extremes of temperature, rain, humidity, condensation and vibration. Boats, just like automobiles, have a notoriously noisy electrical environment and [Matti] has paid special attention to noise and surge suppression throughout the board. The board can work with either 12 V or 24 V bus systems since the on board DC-DC converter is rated up to 32 V input. Connections between the board and the outside world need to be very robust, so it is designed to accept various types of connectors depending on how robust you want it to be.

The Sailor Hat is based around a standard ESP32-WROOM-32 module. Interfaces include a CAN bus transceiver, opto-coupled input and output, I2C, 1-wire and QWIIC interfaces, USB Micro-B programming conector, plus a couple of buttons and LEDs. All of the ESP32 GPIO pins are terminated on a GPIO header, with jumper options to disable terminations to the standard interfaces and instead route them to the GPIO header as needed. Additionally, there’s a generous prototyping area to add additional hardware to the board. Hardware design files are hosted on the project repository on GitHub.

On the software side, there are several frameworks that can be used, with PlatformIO, SensESP, ESPHome and Visual Studio Code being the recommended choices. Or you could use any of the widely available SDK’s for the ESP32 platform — Espressif SDK, Arduino Core for ESP32, MicroPython, NodeMCU or Rust.

[Matti]’s NMEA 2000 USB gateway example is a good way to get a grip on hardware assembly and software installation required to build a practical project using the Sailor Hat. The board is designed to withstand a harsh electrical environment. But it’s mechanical installation obviously requires greater care if it has to survive marine applications. The Sailor Hat can be installed in commonly available, 100x68x50 mm or larger plastic waterproof enclosures, rated for IP65 or higher. The bulkhead connectors and cable glands also need to be appropriately rated, and the enclosure may possibly need a IP68 rated ventilation plug to take care of environmental cycling within the enclosure.

Forth Module The Size Of A Stick Of Gum

Australian engineer [John Catsoulis] developed a small module called the Scamp2 dedicated to running Forth. The focus of his Udamonic project was not only to highlight Forth, but to make a module which was easy to use and doesn’t require any IDE on your computer. According to the website, these modules have found their niche in education as well as rapid prototyping for product development. His site has some good resources, including several Scamp/Forth example applications such as a model train controller or adding a real-time clock module.

The core of the module is a Microchip PIC24F64GB202 MCU with 64K Flash and 8K RAM. Of this, Forth takes up only 20K of Flash and 2K of RAM. [John] is using FlashForth, a version of Forth which came from [Mikael Nordman] at the University of Queensland almost ten years ago. FlashForth has been implemented on a wide variety of PIC and AVR ATmega processors and has apparently developed quite a following in Australia and elsewhere.

We estimate from the photo that the Scamp is about 80 mm long, just slightly longer than a standard piece of MIL-A-A-20175A Type II chewing gum ( 73 mm ). You can use it as-is, or with the header pins installed, the Scamp can be plugged into a breadboard for easy hacking. Regarding the interfacing of Scamp to other equipment, [John] says “Writing software to use other hardware is very easy, and fun.” We like his attitude.

Here is some more information from his Hackaday.io project page, and he also has a Tindie site. If you want a good overview of using Forth in embedded systems, check out Forth: The Hacker’s Language by our own Forth-guru [Elliot Williams]. Thanks to [Stephen Walters] for sending in the tip.

Continue reading “Forth Module The Size Of A Stick Of Gum”

Fertilizing Plants With A Custom 3D-Printed Pump

For all but the most experienced gardeners and botanists, taking care of the soil around one’s plants can seem like an unsolvable mystery. Not only does soil need the correct amount of nutrients for plants to thrive, but it also needs a certain amount of moisture, correct pH, proper temperature, and a whole host of other qualities. And, since you can’t manage what you can’t measure, [Jan] created a unique setup for maintaining his plants, complete with custom nutrient pumps.

While it might seem like standard plant care on the surface, [Jan]’s project uses a peristaltic pump for the nutrient solution that is completely 3D printed with the exception of the rollers and the screws that hold the assembly together. With that out of the way, it was possible to begin adding this nutrient solution to the plants. The entire setup from the pump itself to the monitoring of the plants’ soil through an array of sensors is handled by an ESP32 running with help from ESPHome.

For anyone struggling with growing plants indoors, this project could be a great first step to improving vegetable yields or even just helping along a decorative houseplant. The real gem is the 3D printed pump, though, which may have wider applications for anyone with a 3D printer and who also needs something like an automatic coffee refilling machine.