Pi-Powered Robot Plays Puzzle & Dragons

Have you heard of the iPhone game Puzzle & Dragons? We understand it’s big in Japan. The puzzle part is all about rearranging colored orbs and grouping them together so they disappear and give you points. It’s also part RPG—each color is linked to a little guy, and every combo makes the matching-colored guy a little stronger. Then you fight monsters and take loot.

A YouTube user named [Junya Sakamoto] built a robot to play the game for him. It analyzes the board to come up with the best possible series of moves and then executes them using a Raspberry Pi. You can see what the robot is planning on the screen of a connected laptop. A couple of motors controlled with a Gertbot move a stylus up and down the screen and the phone itself back and forth.

There are two videos after the break. The first one is a combination build and demo video that proves this robot can do a lot more than just while away the hours playing Puzzle & Dragons. The second video demonstrates just how awesome it is at playing Puzzle & Dragons.

We like game-playing robots quite a bit around here. Here’s a Legoduino robot that plays Jurassic Park Builder. This other robot was built to test apps, but it plays Angry Birds in its spare time.

Continue reading “Pi-Powered Robot Plays Puzzle & Dragons”

A Wireless Wood Stove Monitor

[Michel] has a wood stove in his basement for extra heat in the winter. While this is a nice secondary heat source, he has creosote buildup in the chimney to worry about. [Michel] knows that by carefully monitoring the temperature of the gases in the chimney, he can hit the sweet spot where his fire burns hot enough to keep the creosote under control and cool enough that it doesn’t burn down the house. To that end, he built a wireless wood stove monitor.

The first version he built involved an annoying 20 foot run between the basement and living room. Also, the thermocouple was mounted on the surface and made poor contact with the chimney. Wood Stove Monitor 2.0 uses a probe thermometer on an Exhaust Gas Temperature (EGT) thermocouple to measure the temperatures. The intel is fed to a thermocouple amplifier to provide a cold-compensation reference. This is shielded so that radiant heat from the stove doesn’t compromise the readings. An nRF24L01+ in the basement monitoring station communicates with another module sitting in the living room display so [Michel] can easily find out what’s going on downstairs. When it’s all said and done, this monitor will be part of a bigger project to monitor power all over the house.

Interested in using a wood stove to help heat your house? Why not build your own?

Repairing Vintage Clock Movements

It’s obvious that [Matthew] cares a great deal for vintage electric clocks. He is especially fond of the bedside alarm variety, which in our experience cast a warm orange glow on the numbers and emitted a faint, gentle hum. [Matthew] has written up a thorough treatment of Sunbeam movements in particular that covers identification, disassembly, cleaning, and repair.

These workhorse timepieces are cheap and fairly plentiful if you work the estate sale or thrift store circuit. Sometimes there is a bit of trouble with motor pinions disintegrating or the teeth wearing down on the nylon gears. The decades-old petroleum lubricant combined with heat from the spinning rotor can eat away at the motor pinion, causing it to crumble if disturbed.

Wishing to save some of these clocks from landfills, [Matthew] designed motor pin replacements specifically for Sunbeam electric movements, the relatively  inexpensive alternative that graced many a mid-century household clock. He only had the shaft and a broken original to work with, but was able to design a sturdy acrylic replacement using this involute spur gear builder to generate a DXF file. Then it was just a matter of creating an STL file with Rhino 3D and shipping it off to Shapeways.

If you’ve ever wanted to get into clock or watch repair, this looks like a great way to get your feet wet unless you’re ready for some serious vintage watch repair. There’s no need to reinvent the pinion because [Matthew] sells them through his site. If you have a printer, the STL files await you.

Hard Drive Disassembly is Easy and Rewarding

Have any dead hard drives kicking around? Hackaday alum [Jeremy Cook] shows how easy it is to disassemble a hard drive to scavenge its goodies. The hardest part is having the patience and the tools to get past all those screws that stand between you and the treasure inside.

The case screws are frequently of the Torx variety. Any self-respecting hacker probably has one or two of these already, but if you’re in the market, [Jeremy] recommends a nice set that looks way better than ours. Once the case is open, you can find rare earth magnets, bearings, and one or more platters.

Those terrifically strong magnets are good for all kinds of projects. Glue a couple of them to the back of an attractive piece of wood, mount it on the kitchen wall, and you have yourself a knife block. Keep a couple on the bench to temporarily magnetize tools. Use them to build a pickup to amplify a cigar box guitar or thumb piano. Or run the pickup into a small amplified speaker and wave it like a stethoscope near your electronics to hear them hum. As far as liberating the magnets goes, [Jeremy] resorted to clamping his in a vise and using a hammer and chisel to pry it away from the actuator hardware.

You’ve no doubt seen clocks made from old hard drives that were kept mostly intact. Many makers including [Jeremy] will extract the shiny platters to use as bases for clock faces and engrave the numbers, etch them, or glue them on. Those platters also make excellent chimes. Even if you just hang one platter off of a finger and tap it with a fingernail, it sounds really nice.

If simple chimes don’t really butter your muffin, there are all kinds of sonic projects for dead hard drives. How about making a microphone or speakers? Maybe an HDD MIDI controller or a synthesizer is more your speed. Speaking of synths, watch [Jeremy] take a hard drive apart to some sweet sounds after the break.

Continue reading “Hard Drive Disassembly is Easy and Rewarding”

Russian Rocket Tech Comes In From the Cold

Decades after the end of the space race, an American rocket took off from Cape Canaveral. This was a routine launch to send a communications satellite into orbit, but the situation was an historic first. The rocket in question was driven by a powerful Russian engine unlike any ever built in the States. Although this particular engine was new, the design dated back to the space age.

By the early 1960s, the Russians were leaps and bounds ahead of the United States in terms of space exploration. They had already launched Sputnik and sent Yuri Gagarin to orbit the Earth. All in all, the Russians seemed poised to send a man to the moon. Russian technology had the Americans worried enough to spy on them with satellites, and the images that came back revealed something spectacular. Out in the Kazakh desert, the Russians were building an enormous causeway and two launch pads. As it turns out, the US had every reason to be worried.

Continue reading “Russian Rocket Tech Comes In From the Cold”

One Hoss Shay and Our Society of Obsolescence

Legend has it that Henry Ford would send engineers out to junkyards all over the US looking for Fords. They were supposed to study each one they found and make note of any parts that had not failed. But it wasn’t so that he could start making all of those parts stronger. Instead, Ford allegedly used this data to determine where he could cut corners in future production runs so as not to waste money by making any part last longer than any other part.

Most things tend to break down rather than completely giving out. Usually it’s only one or two components that stop working and the rest of it is still serviceable. And this is a good thing. It’s what lets us repair PCBs or scavenge parts off them, drive our cars longer, and help save each other’s lives through organ donor programs. Can you imagine how different life would be if each part of every thing failed at the same time?

Continue reading “One Hoss Shay and Our Society of Obsolescence”

Bone Up on Your Multiplication Skills

John Napier was a Scottish physicist, mathematician, and astronomer who usually gets the credit for inventing logarithms. But his contributions to simplifying mathematics and building shorthand solutions didn’t end there. In the course of performing the many calculations he needed to practice these subjects in the 1500s, Napier invented a kind of computing mechanism for multiplication. It’s a physical manifestation of an old system known as lattice multiplication or gelosia.

Lattice multiplication makes use of the multiplication table in order to multiply huge numbers together quickly and easily. It is thought to have originated in India and moved west into Europe. When the lattice method reached Italy, the Italians named it gelosia after the trellised window covering it resembled, which was commonly used to keep prying eyes away from one’s possessions and wife.

Continue reading “Bone Up on Your Multiplication Skills”