Problem: build a combined anemometer and wind vane where the pivots for both sensors are coaxial. Solution: turn an old universal motor into a step-wise potentiometer for the wind vane, and then pull a few tricks to get the whole thing assembled.
We have to admit that when we first saw [Ajoy Raman]’s Instructables post, we figured that he used a universal motor to generate a voltage from the anemometer. But [Ajoy]’s solution to the coaxial shafts problem is far more interesting than that. A discarded universal motor donated its rotor and bearings. The windings were stripped off the assembly leaving nothing but the commutator. 1kΩ SMD resistors were soldered across adjacent commutator sections to form a series resistance of 22kΩ with taps every 1k, allowing 0 to 2.2V to be read to the ADC of a microcontroller depending on the angle of the vane.
As clever as that is, [Ajoy] still had to pull off the coaxial part, which he did by drilling out the old motor shaft from one end to the other using just a drill press. The anemometer shaft passes through the hole in the shaft and turns a small DC motor to sense wind speed.
There might have been other ways to accomplish this, but given the constraints and the low cost of this solution, our hats are off to [Ajoy]. We’re a little concerned with that motor used for the anemometer, though. It could result in drag when used as a generator. Maybe a better solution would be a Hall-effect sensor to count rotations of a hard drive rotor.
Continue reading “Old Motor Donates Rotor for Coaxial Wind Vane and Anemometer”
A frequent early project for someone learning to use a microcontroller such as an Arduino board involves hooking up a temperature sensor and an LCD display to make a digital thermometer. Not many components are involved, but it provides a handy practical introduction to interfacing peripherals. Once you’ve passed that step in your tech education, do you ever return to thermometers? Probably not, after all what can you add to a thermometer but a sensor and a display?
Perhaps if you have asked yourself that question you might be interested in [Richard Stevens]’s thermometer project, as he refers to it, a Comfort Thermometer Display. It takes the form of an Ikea Ribba frame inset with 517 LEDs arranged as a central set of seven segment displays, a ring of bar graphs, and an outer ring of RGB LEDs. Behind the scenes is a mass of cabling, and four shaped pieces of stripboard to fit the area around the LEDs. The display cycles through readings for temperature, heat index, and humidity.
Powering it all are a brace of microcontrollers: an ATMega328 for the 7-segments and a range of PICs controlling the bar graphs and RGB LEDs. Another PIC handles RF communication with the sensors, which are housed in a remote box. We’ve embedded the video of the device in operation below the break, and we’re sure you’ll agree it’s an impressive piece of work.
Continue reading “Comfort Thermometer With Impressive LED Display”
The Weatherclock is more than just a clock sporting Nixie tubes and neon lamps. There is even more to it than the wonderful workmanship and the big, beautiful pictures in the build log. [Bradley]’s Weatherclock is not only internet-connected, it automatically looks up local weather and sets the backlights of the numbers to reflect current weather conditions. For example, green for roughly room temperature, blue for cold, red for warm, flashing blue for rain, flashing white for lightning, scrolling white for fog and ice, and so on.
The enclosure is custom-made and the sockets for the tubes are seated in a laser-cut plastic frame. While seating the sockets, [Bradley] noticed that an Adafruit Neopixel RGB LED breakout board fit perfectly between the tube leads. By seating one Neopixel behind each Nixie indicator, each number could have a programmable backlight that just happened to look fabulous.
With an Electric Imp board used for WiFi the capabilities of the Weatherclock were rounded out on the inside. On the outside, a custom enclosure ties it all together. [Bradley] says his family had gotten so used to having the Weatherclock show them the outside conditions that they really missed it when it was down for maintenance or work – which shouldn’t happen much anymore as the project is pretty much complete.
It’s interesting to see new features in Nixie clocks. Nixie tubes have such enduring appeal that using them alone has its own charm, and at least one dedicated craftsman actually makes new ones from scratch.
[Petru] seems to have designed his weather ticker project with beginners in mind. Leveraging the inexorable forces of both the Raspberry Pi and cheap online auction house modules, it’s nearly the Hackaday equivalent of painting by numbers. But not everyone is a Picasso, and encouraging beginners to get their feet wet by painting happy little trees is a good cause.
Behind the simplicity is actually a clever architecture. An installation script makes installing the right Raspbian distro simple, and installs a few scripts that automatically update the user code from a GitHub repository. To change the code running on the machine, you can upload a new version to GitHub and press the reset button. (We would also want a way to push up code changes locally, for speed reasons.) Something like this is a great idea for a permanent Pi-based IoT device.
But as a first project, the hope is that something like this will encourage folks who find code too abstract, but who are nonetheless drawn by the allure of blinking lights, to play around with code. And unsurprisingly, this has already been entered in our Enlightened Raspberry Pi Contest which focuses on the simple-yet-impressive stuff you can do with a tiny computer and some electronics.
When you hear “gravity waves” or “sprites”, you’d think you would know what is being discussed. After all, those ripples in space-time that Einstein predicted would emanate from twin, colliding, black holes were recently observed to much fanfare. And who doesn’t love early 8-bit computer animations? So when we were browsing over at SpaceWeather we were shocked to find that we were wrong twice, in one photo (on the right). Continue reading “Two Words That Don’t Mean What You Think They Do”
Before the information age, it wasn’t quite as easy to glean information about the weather. Sure, there were thermometers and barometers and rhymes about the sky, but if you lived in or near Germany back then you might have also had access to something called a “weather house” which could help predict rain. [Moritz] aka [Thinksilicon] found one of these antequated devices laying around, and went about modernizing it. (Google Translate from German)
A traditional weather house is essentially a hygrometer housed in an intricate piece of artwork. Two figures, typically a man and woman, are balanced on a platform that is suspended in the middle by a small section of horsehair. When the humidity is low, the hair tightens up and turns the platform one way, and when humidity is high — suggesting rain is coming — it turns the other way. When the man comes out of the house, it predicts rainfall.
To get the weather house upgraded, [Moritz] outfitted the front with an OLED display which replaced the traditional thermometer. Instead of using horsehair to spin the figures he installed a small servo on the platform. The entire house is controlled by an ESP8266 which pulls data from the Open Weather API and spins the figures based on the information it receives.
Much like unique clocks, we enjoy interesting weather indicating/forecasting builds. This one’s right up there with using squirrels to predict the weather, or having a small weather-recreation right on your bookshelf.