Better Sailing Computers With Wearable Electronics

March 19, 2016 by Brian Benchoff 2 Comments

Sailing – specifically small boats in regattas – is a hobby that requires a lot of skill. Like any hobby, there are devices and electronics to make the hobby easier. For sailing, its tactical sailing compasses and GPS units. Remember, you probably don’t want to sail in a straight line, and that means offloading decades of experience to electronics. Instead of spending hundreds of dollars on a sailing computer, [Brook] thought it would be a better idea to build his own robot sailor from a Raspberry Pi and a Pebble smartwatch.

The sensors required for a sailing computer are par for the course – a Ublox GPS unit, a magnetometer, an acceleratometer, and a gyro. Being used on a sailboat also means there’s an anemometer thrown into the mix. These parts are stuffed into a waterproof polycarbonate field box with a USB power bank battery and a Bluetooth USB dongle.

With the hardware in place, it was time to write the software. The UI for this device is a Pebble smartwatch, which means there was a lot of futzing around with C# and Mono. This device is also a sailing data recorder, meaning [Brook] can integrate this project with VisualSail, a desktop application he wrote a few years ago to create 3D replays of sailing races using GPS data.

The Raspberry Pi Zero contest is presented by Hackaday and Adafruit. Prizes include Raspberry Pi Zeros from Adafruit and gift cards to The Hackaday Store!
See All the Entries

Another Use For Old Hard Drive Parts: Anemometer

February 7, 2016 by Elliot Williams 39 Comments

So you’ve just taken apart a hard drive, and you’re looking at all the pieces on your desktop. You’re somehow compelled to use them all in different projects. Why not pull out that very high quality bearing that keeps the platters spinning at high RPMs and build this simple anemometer with it? That’s what [Sergei Bezrukov] did, and it looks like a perfect el cheapo project.

The build is fairly low-tech and entirely sufficient. The cups are made from plastic containers that used to contain pantyhose. A Hall-effect sensor and a magnet take care of measuring the rotations, feeding its signal into a PIC that calculates the wind speed from the revolution rate. The rest of the housing is PVC, with some other miscellaneous parts found at the hardware store.

To calibrate the device, [Sergei] made a second hand-held unit that he could (presumably) drive around in a car to get a baseline wind speed, and then note down the revolution rate. Once you’ve got a good reference, holding the portable unit up to the permanent one transfers the calibration.

But the star of the show, that lets the anemometer spin effortlessly, is the sweet bearing that used to spin a hard-drive platter. If you haven’t played with one of these bearings before, you absolutely should. We just ran a post on taking apart a hard drive for its spare-parts goodness so you have no excuse. If you’re feeling goofy, you can mount one onto a board, step on it with the ball of your foot, and spin. They’re quality bearings, and you’ll be surprised how quickly you can spin as you pull your arms in.

Thank [Matt] for the tip!

Old School Gauges Let You Know Which Way The Wind Blows

January 27, 2016 by Dan Maloney 14 Comments

When your passion is a sport that depends on Mother Nature’s cooperation, you need to keep a close eye on weather conditions. With this in mind, and not one to let work distract him from an opportunity to play, [mechanicalsquid] decided to build a wind-monitoring gauge with an old-school look to let him know when the wind is right for kitesurfing.

Being an aficionado of big engineering helped [mechanicalsquid] come up with a style for his gauge – big old dials and meters. We hesitate to apply the “steampunk” label to every project that retasks old technology, but it sure looks like a couple of the gauges he used could have been for steam, so the moniker probably fits here. Weather data for favorite kitesurfing and windsurfing locales is scraped from the web and applied to the gauges to indicates wind speed and direction. [mechanicalsquid] made a valiant effort to drive the voltmeter coil directly from the Raspberry Pi, but it was not to be. Servos proved inaccurate, so steppers do the job of moving the needles on both gauges. Check out the nicely detailed build log for this one, too.

For more weather station fun be sure to check out this meter-based weather station with a slightly more modern look. And for another build in the steampunk style, this vintage meter and Nixie power display is sure to impress.

Raspberry Pi Wind Measurement

January 16, 2016 by Rud Merriam 18 Comments

A well organized approach to a project is a delight to see. [Pavel Gesyuk] takes just that approach with the experiments on his blog. Experiment 13 is a multi-part series using a Raspberry Pi as the heart of a weather station. [Pavel] is looking at wind speed and direction, and temperature measurement, plus solar power for the station. One of his videos, there are many, is after the break.

The anemometer and direction sensors are stock units wired to a Raspberry Pi A+ using an analog to digital daughter board. The data from the temperature sensor is acquired using I2C. During one part of the experiment he uses an EDIMAX WiFi adapter for collecting the data.

Python is [Pavel’s’ language of choice for development and freely shares his code for others to see. The code collects the data and displays it on a monitor connected to the Pi. The experiment also attempts to use solar power to charge batteries so the station is not dependent on mains power.

The mechanical assembly shows attention to detail commensurate with his project presentation and we respect how well organized the work is.

Continue reading “Raspberry Pi Wind Measurement” →

Ultrasonic Anemometer For An Absurdly Accurate Weather Station

August 21, 2013 by Brian Benchoff 41 Comments

With his meteorological interests, [Carl] builds weather stations. Temperature and humidity sensors are a dime a dozen, but with his DIY ingenuity, [Carl] has built some very interesting and complicated devices. The latest of which is an ultrasonic wind sensor that uses the time of flight of ultrasonic pulses to detect how fast the wind is blowing.

[Carl]’s sensor uses four ultrasonic transducers aligned to North, South, East, and West to detect the wind speed. By measuring the time it takes an ultrasonic pulse to travel between the sensors indoors, Subtracting the in-situ measurement gives him the time of flight for each axis, and thus the wind speed.

It’s an impressive display of engineering that comes with an amazingly detailed design report. After three months of operation, [Carl] has found his ultrasonic anemometer is better than the traditional mechanical ‘egg-cup’ anemometer at measuring low wind speeds. The only real problem with the build is the fact the design makes a great bird perch, but some fine steel wire quickly corrected that problem.

Umbrella-based Windmills

August 29, 2012 by Mike Szczys 13 Comments

[Niklas Roy] is at it again. He’s applying wind power to his projects by using umbrellas. He was inspired by the shape of an anemometer, and umbrellas turned out to be a great choice because they’re cheap and easy to find.

Anemometers measure wind speed by capturing it with egg-shaped sails (in fact, we’ve seen them built from plastic Easter eggs before). The umbrellas have a much larger area and will capture more wind. Still it’s a big jump from measuring wind speed to generating energy. That’s why he’s not trying to generate electricity, but instead using the mechanical force directly. He took a page from one of last year’s projects and used the dual umbrella setup to power a music box, thereby reinventing the wind chime. The triple-umbrella unit seen above serves as a bubble machine, driving a series of plastic rings through a soapy solution and letting the wind do the rest. We’ve embedded his demo video after the break.

Continue reading “Umbrella-based Windmills” →