DIY Thermal Imager Uses DIY Gaussian Blur

September 29, 2019 by Donald Papp 18 Comments

Under the right circumstances, Gaussian blurring can make an image seem more clearly defined. [DZL] demonstrates exactly this with a lightweight and compact Gaussian interpolation routine to make the low-resolution thermal sensor data display much better on a small OLED.

[DZL] used an MLX90640 sensor to create a DIY thermal imager with a small OLED display, but since the sensor is relatively low-resolution at 32×24, displaying the data directly looks awfully blocky. Gaussian interpolation to improve the display looks really good, but it turns out that the full Gaussian interpolation isn’t a trivial calculation write on your own. Since [DZL] wanted to implement it on a microcontroller, the lightweight implementation was born. The project page walks through the details of Gaussian interpolation and how some effective shortcuts were made, so be sure to give it a look.

The MLX90640 sensor also makes an appearance in the Open Thermal Camera, one of the entries for the 2019 Hackaday Prize. If you’re interested in thermal imaging, don’t miss this teardown of a thermal imaging camera.

Hello: A Mini Badge For CCCamp

August 21, 2019 by Jenny List 1 Comment

Badgelife culture is our community’s very own art form, with a plethora of designs coming forth featuring stunning artwork, impressive hardware, and clever software tricks. But sometimes a badge doesn’t need a brace of LEDs or a meme-inspired appearance to be a success, it just needs to be very good at what it does.

A perfect example is [Gavan Fantom]’s Hello mini badge. The hardware is fairly straightforward, it’s just a small square PCB sporting a LPC1115 microcontroller, 8Mb Flash chip, piezo speaker, and an OLED display. Its functionality is pretty simple as well, in that it exists to display text, images, or short animations. But the badge hides a very well-executed firmware that provides a serial terminal and zmodem file upload capability as well as an on-device interface via a small joystick. Power comes from a 500 mAh lithium-polymer cell, for which the badge integrates the usual charger and power management hardware.

There’s a variety of possibilities for the badge, but we’d guess that most owners will simply use it to display their name with perhaps a little animation. A bit of nifty processing of some video could perhaps get something approaching watchable video on it though, opening up the entertaining possibility of displaying demos or other video content.

[Gavan] will have some of the Hello badges at the upcoming CCCamp hacker camp in Germany if you’re interested, and should be easy enough to find in the EMF village.

A Tiny Train Departure Board, Just Like The Real Thing

August 5, 2019 by Jenny List 8 Comments

If you travel on the British rail system, you’ll be familiar with the ubiquitous orange dot-matrix departure display boards. At a glance they tell you the expected arrival times of the next few trains, where they are headed, and at the bottom the current time. [Chris Crocker-White] was inspired by a Tweet to recreate one of these displays in miniature and hang it under his monitor.

The hardware is a Raspberry Pi Zero with an OLED screen, in a custom 3D-printed case. A soldered USB cable takes power from the monitor’s USB ports. Software wise it’s a demonstration vehicle for the Balena cloud service that pulls its data from their transport API, but the choice of dot matrix typeface is perfect and absolutely looks the part.

There is some question as to whether a project such as this one should need a cloud service as its backend, and of course it serves as a demonstration piece rather than a definitive way to enact a departure board. It does however bring a ready-packaged API for transport data, which given that many data sources can be opaque, is a useful feature.

Train time displays seem to be a popular choice on the Eastern side of the Atlantic, here’s another British one, and one from Ireland.

Thanks [Pyrofer] for the tip.

Tiny Game System Is An Experiment In Minimalism

July 25, 2019 by Tom Nardi 22 Comments

Many people assumed the smartphone revolution would kill the dedicated handheld game system, and really, it’s not hard to see why. What’s the point of buying the latest Nintendo or Sony handheld when the phone you’re already carrying around with you is capable of high-definition 3D graphics and online connectivity? Software developers got the hint quickly, and as predicted, mobile gaming has absolutely exploded over the last few years.

But at the same time, we’ve noticed something of a return to the simplistic handheld systems of yore. Perhaps it’s little more than nostalgia, but small bare-bones systems like the one [Mislav Breka] has entered into the 2019 Hackaday Prize show that not everyone is satisfied with the direction modern gaming has gone in. His system is specifically designed as an experiment to build the most minimal gaming system possible.

In terms of the overall design, this ATMega328 powered system is similar to a scaled-down Arduboy. But while the visual similarities are obvious, the BOM that [Mislav] has provided seems to indicate a considerably more spartan device. Currently there doesn’t seem to be any provision for audio, nor is there a battery and the associated circuitry to charge it. As promised, there’s little here other than the bare essentials.

Unfortunately, the project is off to something of a rocky start. As [Mislav] explains in his writeup on Hackaday.io, there’s a mistake somewhere in either the board design or the component selection that’s keeping the device from accepting a firmware. He won’t have the equipment to debug the device until he returns to school, and is actively looking for volunteers who might be interested in helping him get the kinks worked out on the design.

Freeform ESP8266 Network Attached Data Display

May 31, 2019 by Tom Nardi 10 Comments

Like many of us, [Josef Adamčík] finds himself fascinated with so-called “freeform” electronic designs, where the three dimensional circuit makes up sections of the device’s structure. When well executed, such designs really blur the line between being a practical device and an artistic piece. In fact his latest design, an ESP8266 MQTT client, would seem to indicate there might not be much of a “line” at all.

The inspiration for this project actually comes from something [Josef] had worked on previously: an ESP8266-based environmental monitoring system. That device had sensors to pick up on things such as humidity and ambient light level, but it didn’t have a display of its own; it just pushed the data out onto the network using MQTT. So he thought a companion device which could receive this environmental data and present it to him in a unique and visually appealing way would be a natural extension of the idea.

As the display doesn’t need any local sensors of its own, it made the design and construction much easier. Which is not to say it was easy, of course. In this write-up, [Josef] takes the reader through the process of designing each “layer” of the circuit in 2D, printing it out onto paper, and then using that as a guide to assemble the real thing. Once he had the individual panels done, he used some pieces of cardboard to create a three dimensional jig which helped him get it all soldered together.

On the software side it’s pretty straightforward. It just pulls the interesting bits of information off of the network and displays it on the OLED. Right now it’s configured to show current temperature on the display, but of course that could be changed to pretty much anything you could imagine if you’re looking to add a similar device to your desktop. There’s also a red LED on the device which lights up to let [Josef] know when the batteries are getting low on the remote sensor unit; a particularly nice touch.

If you’d like to see more of these freeform circuits, we’d advise you to checkout the finalists for our recently concluded “Circuit Sculpture” contest. Some of the finalists are truly beyond belief.

Desktop Weather Monitor Leaves Nothing To Chance

May 19, 2019 by Tom Nardi 4 Comments

[Mirko Pavleski] has put together a little weather station for himself that combines Internet-sourced forecasts with physical sensor data to give him a complete view of his local conditions. There’s no shortage of weather applications for our smartphones and computers that will show us the current local conditions and the forecast for the next couple of days. It’s so easy to pull weather data from the various APIs out there that you even see the functionality “baked in” to different gadgets these days. Of course, you can dig through every weather API in the world and not find the temperature and humidity inside your office; for that, you need your own sensors.

[Mirko] took a somewhat unconventional approach by essentially building two totally separate weather devices and packing them into one enclosure, which gives the final device a rather unique look thanks to the contrasting display technologies used.

Local conditions are detected by an Arduino Nano connected to a BMP180 sensor and displayed on a Nokia 5110 LCD. The screen shows not only real-time temperature and barometric pressure, but the change in pressure over the last several hours. The three-day forecast, on the other hand, is provided by a NodeMCU ESP8266 development board connected to the increasingly ubiquitous 0.96 inch OLED.

If you’re not into the whole duality thing and would rather do it all on the same device, you might be interested in one of the ESP8266 weather monitors we’ve seen in the past.

Building An ESP8266 Game System With MicroPython

May 16, 2019 by Tom Nardi 6 Comments

After a seemingly endless stream of projects that see the ESP8266 open doors or report the current temperature, it can be easy to forget just how powerful the little WiFi-enabled microcontroller really is. In fact, you could argue that most hackers aren’t even scratching the surface of what the hardware is actually capable of. But that’s not the case for [Brian Wagner] and his students from the Kentucky Country Day School.

Their project, the GamerGorl, is a completely custom handheld game system running on a Wemos D1 Mini development board. The team’s PCB, which was developed over several iterations, is essentially a breakout board which allows them to easily connect up peripheral devices. Given the low total component cost of the GamerGorl and relative simplicity of its construction, it looks like a phenomenal project for older STEM students.

Beyond the ESP8266 board, the GamerGorl features a SSD1106 1.3″ OLED display, a buzzer for sound effects, two tactile buttons, and an analog joystick originally intended for an Xbox controller. Around the backside there’s a WS2812B RGB LED strip that’s at least partially for decoration, but it’s also actively used in some of the games such as the team’s take on Simon.

Even if you aren’t in the market for a portable game system, the GameGorl does provide an interesting case study for MicoPython applications on the Wemos D1 Mini. Browsing through the team’s source code as well as the helpful hints that [Brian] gives about getting the software environment up and running could be useful if you’re looking to expand your ESP8266 programming repertoire. We’d also love to see this device running the “ESP Little Game Engine” we covered recently.

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