Easy To Build Solar Pool Heater Saves Money And Keeps You From Freezing

For those cool summer days it’s sometimes nice to have a heated pool — but usually pretty expensive too. Looking for a simpler solution [Martin] came up with his own solar pool heater for under $100!

He’s copied the basic design of a solar pool heater but managed to do it using fairly cheap parts from the hardware store. It consists of three 100′ lengths of 1/2″ drip irrigation hose, and the way he’s connected them is rather ingenious. Using a half inch piece of copper pipe and a blow torch, he was able to squeeze the pipe into one hose end and then the other for a permanent seamless connection. He then coiled the resulting hose into a large circle by interweaving string back and forth to keep its shape.

A 12V utility pump coupled with a timer allows water to sit in the hose under the sun for one hour, at which point it cycles the system for 10 minutes, pumping the warm water into the pool, and refilling itself with cool water from the bottom of the pool. This one is only made for a small above ground pool, but the design could easily be doubled or even tripled for larger pools. You could also throw in a PID temperature controller or even an Arduino to make it even better… but it sounds like it works quite well by itself with a timer.

Combine this with a compost-based hot water system for indoors and you’ll really be cutting the expense associated with your hot water needs!

Nerds Helping Sea Turtles

Sea Turtle Nest Monitoring Device

Life as a sea turtle can be rough. Not only are turtles trying to survive predators, destruction of habitat, fishing nets, and pollution, but only about 1% of hatchlings survive to face those challenges in the first place. Enter [Samuel Wantman] and a new volunteer hacker group called Nerds Without Borders, with their first order of business of creating an egg-shaped monitoring device for sea turtle nests.

Sea turtles are protected under the Endangered Species Act, which goes to great lengths to protect certain species from human activity. The ultimate goal of the project is to help people and sea turtles better coexist under this law by more accurately predicting hatching times. A suite of sensors and a cell network antenna are placed in a plastic “egg” that can be buried in a nest after a sea turtle lays the real eggs. The sensors detect vibrations within the eggs as the embryos grow, which is an indication that the tiny turtles are about to break free of their eggs and head for the open ocean!

Click past the break for more on this project.

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Dots And Dashes… On A Roll!

morse code device

Morse code was once a staple of the communications industry, but with advancing technology it has become relegated almost exclusively to movies and a niche group of ham radio operators. [Jan] has created a device which might not put a stop to this trend, but will at least educate children on the basics of how Morse code works by visually displaying Morse code as it’s generated.

The setup is fairly simple. An old momentary switch (which could easily be used in an actual Morse code setup) activates two pieces of circuitry. The first is a 555 timer circuit that creates an audible tone when the switch is pressed so the user can hear exactly what an operator would hear when decoding a real Morse code message.

The second piece of circuitry is where the real genius lies: a continuously spinning roll of glow-in-the-dark tape is placed in front of a white LED. When the switch is pressed, the LED turns on, which produces dots and dashes on the roll of tape as it passes by. This eliminates the need for rolls of paper or a more complicated moving pen/pencil setup to draw on the paper which might also be less child-proof.

While [Jan] built this as a toy, the children who used it thoroughly enjoyed it! They even decoded some Morse code messages and used the device to practice on it. After a while they’ll easily be able to master the Morse code trainer!

Parallax Propeller 1 Goes Open Source

OpenPropellerProjectOpenSourceProp1Banner

Parallax has embraced open source hardware by releasing the source code to its Propeller 1 processor (P8X32A). Designed by [Chip Gracey] and released in 2006, the 32-bit octal core Propeller has built up a loyal fan base. Many of those fans have created development tools for the Propeller, from libraries to language ports. [Ken, Chip], and the entire Parallax team have decided to pay it forward by releasing the entire source to the Propeller.

The source code is in Verilog and released under GNU General Public License v3.0. Parallax has done much more than drop 8-year-old files out in the wild.  All the configuration files necessary to implement the design on an Altera Cyclone IV using either of two different target boards have also been included. The DE0-Nano is the low-cost option. The Altera DE2-115 dev board is more expensive, but it also can run the upcoming Propeller 2 design.

The release also includes sources for the mask ROM used for booting, running cogs, and the SPIN interpreter. [Chip] originally released this code in  2008. The files contain references to PNut, the Propeller’s original code name.

We’re excited to see Parallax taking this step, and can’t wait to see what sort of modifications the community comes up with. Not an Altera fan? No problem – just grab the source code, your favorite FPGA tools, and go for it! Starved for memory? Just add some more. 8 cogs not enough? Bump it up to 16.  The only limits are the your imagination and the resources of your target device.

Interested in hacking on a real Propeller? If you’re in Las Vegas, you’re in luck. A Propeller is included on each of the nearly 14,000 badges going to DEFCON 22 attendees. While you’re there, keep an eye out for Mike and The Hackaday Hat!

Rolly Bot Puts A New Spin On Independent Wheel Control

rolly bot

All of [Darcy]’s friends were making wheeled robots, so naturally, he had to make one too. His friends complicated theirs with h-bridges and casters for independent wheel maneuvering, but [Darcy] wanted something simpler. A couple of 9g servos later, the Rolly Bot was born.

Rolly Bot is self-balancing because of its low center of gravity. Should it hit a wall, the body will flip over, driving it back in the other direction. The BOM comes to a whopping $10, and that includes continuous rotation servos. It does not include the remote control capability he added later, or the cost of the CNC you would need to completely replicate this build. He even made a stand so he could test the wheels during programming.

[Darcy]’s code is on his site along with some pictures of another version someone else built. Watch Rolly Bot roll around after the jump.

How would you make this build even simpler? Tell us in the comments.

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Testing VR Limits With A Raspberry Pi

vrpi

Virtual Reality by function pushes the boundaries of what we perceive as existence, tricking the mind into believing that the computer generated environment that the user is thrust into actually contains a real place. So in the spirit of seeing what is possible in VR, a developer named [Jacques] hooked up a Raspberry Pi to an Oculus Rift. He used a computer graphics rendering API called OpenGL ES, which is much like any mobile platform found these days, to render a floating, rotating cube.

All his tests were done on a Release build which utilized the official vertex and fragment shaders. There was no attempt to optimize anything; not like there would be much to do anyways. The scene was rendered twice at 16 milliseconds per frame. From there, he attempted 27 ms per frame with texture, followed by 36 ms/frame, and then 45.

The code used can be found on [Jacques]’s Github account. A simple improvement would use a Banana Pi for better processing speed. However, don’t expect any spectacular results with this type of setup. Really, the project only proves that it’s possible to minimize a VR experience into something that could become portable. And in the same vein, the Pi + Oculus integration can produce an uncomfortable lagging effect if things are not lined up properly. But once the energy/computing power issues are addressed, VR devices could transform into a more fashionable product like Google Glass, where a simple flip of a switch would toggle the view between VR and AR into a something more mixed. And then a motion sensing input camera like this Kinect-mapping space experiment could allow people all over the world to jump into the perspectives of other reality-pushing explorers. That’s all far down the line though, but this project lays the foundation for what the future might hold.

To see [Jacques]’s full set up, view the video after the break.

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George Crowdsourcington: A 3D Printed, Community Built Statue

George Crowdsourcington and Distributed Ben Franklin

Macro 3D printing is some cool stuff — but it’s extremely time consuming and can be very expensive. Introducing We The Buildersa 3D printing crowd source site which creates large scale projects the whole country can enjoy.

Their first project was George Crowdsourcington — a 1:1 copy of the Baltimore George Washington statue made out of 110 individual pieces. They chopped the model up into 4″ cubes and created the website in order to organize and distribute the files. One of their sponsors, Tinkerine Studio, reimbursed the shipping costs for makers who helped print out parts! Since his creation, Crowdsourcington has traveled all over the country, making stops at 3D printing shows in New York, mini-Maker Faires, art galleries, science centers and more — he even did a short residency in the Adafruit office in Manhattan!

It was quite the success, so they’re starting a new statue called the Distributed Ben Franklin. This one has a whopping 198 pieces, and they hope to have it built in time for the Silver Spring and World Maker Faires.

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