If you were to paint a few stereotypes surrounding our community, where would you start? Maybe in apparel habits: the t-shirt from a tech conference, or the ubiquitous hoodie. Or how about leisure pursuits: gaming, or even D&D? There’s one thing I can think of that unites most of us, we have a curious affinity for caffeine. Is it a propensity for working into the dark of the night that’s responsible, or perhaps those of us with ADHD find the alertness helpful, but whatever it is we like our coffee and energy drinks. Rare is the hackerspace without a coffee machine and a fridge full of energy drinks, and I have lost count of the times I have been derided by the coffee cognoscenti among my peers for my being satisfied with a mug of mere instant. Deprived of my usual socialisation over the festive period by the pandemic, and contemplating my last bottle of Club-Mate as I drank it, I took a while to ponder on our relationship with this chemical.
Day: March 10, 2021
High-Altitude Balloon Tracker Does Landing Prediction With Pi Pico
[Dave Akerman]’s ongoing high altitude balloon (HAB) work is outstanding, and we’re all enriched by the fact that he documents his work like he does. Recently, [Dave] wrote about his balloon tracker based on the Raspberry Pi Pico, whose capabilities brought a couple interesting features to the table.
In a way, HAB trackers have a fairly simple job: read sensors such as GPS and constantly relay that data to someone on the ground so that the balloon’s location can be tracked, and the hardware recovered when it ultimately returns to Earth. There are a lot of different ways to do this tracking, and one thing [Dave] enjoys is getting his hands on a new board and making a HAB tracker out of it. That’s exactly what he has done with the Raspberry Pi Pico.
Nothing builds familiarity like actually using a part, and the Pico had some useful things to contribute to a HAB tracker application. For one thing, the Pico has an onboard buck-boost converter that allows it to be powered from a relatively wide voltage range (~1.8 V to 5.5 V), so running it directly from batteries is both possible and desirable from a tracker perspective. But a really useful feature was possible thanks to the large amount of memory on the Pico: dynamic landing prediction.
[Dave] does landing prediction prior to launch based on environmental conditions, but it’s always better if the HAB tracker can also calculate its own prediction based on actual observed events and conditions. A typical microcontroller board like an Arduino doesn’t have enough memory to store the required data upon which to do such calculations, but the Pico does so easily. [Dave]’s new board transmits an updated landing site prediction along with all the rest of the telemetry, making the retrieval process much more reliable.
Want to see a completely different approach to HAB recovery? Check out a payload guided by steerable parachutes.
ESP8266-Powered Receipt Printer Puts RESTful API On Dead Trees
Taking his digital information into the real-world, [Davide Gironi] has built his own note transcriber from a point-of-sale receipt printer and an ESP8266.
You’ve seen these receipt printers at the order window of restaurants. A server puts in an order from any of the machines throughout the restaurant and a paper summary spits out for the chef line to start in on (and even cuts itself off from the roll). Why shouldn’t we have this convenience in our own lives?
The printer communicates using a variant of the Epson Standard Code for Printers, for which [Davide] has written a library and thankfully shared the code. Adding an ESP8266 using a couple voltage regulators and some passive components makes this wireless, except for power. It has all the fun bells and whistles to set up the WiFi credentials and once running, just push the button on the base and it’ll spit out your data.
But wait, where is that data coming from? The web-based settings page lets you configure a URI to the RESTful source of your choosing. (XKCD has one, don’t they?) It also lets you configure header, footer, error messages, and of course your
company hacker logo.
One of our favorite receipt-printer moments was when Hackaday editor of yore [Eliot Phillips] brought a selfie receipt printer to Supercon. We couldn’t find any pictures of that one, so we’ll leave you with the excellent hack [Sam Zeloof] pulled off by cramming one of these into a Polaroid camera.
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