[Dominik’s] daughter had an old toy piano that she loved, but when the batteries started to die down, it played awful tones and sounded generally out of tune. While this is likely something our circuit bending friends might be interested in, [Dominik] preferred when things sounded more cheery.
He considered simply replacing the batteries, but it seemed like a far better idea to do away with them altogether. he hunted around for a solution, and eventually found one at the local IKEA store. He grabbed a LJUSA hand-powered flashlight and disassembled it, saving the crank and circuitry.
He installed the crank on the back side of his daughter’s piano, and mounted the electronic bits inside the toy’s shell. The crank spins a brushless motor, generating an AC current which is rectified to DC before being stored in a capacitor. He says that a 30 second crank will play just a few tunes, which isn’t ideal, though it is better than frequently replacing batteries.
[Nathan]’s son really loves numbers and counting, and one of his favorite things to do is add 1 to a calculator over and over again. Being the awesome dad that he is, [Nathan] built his son a counting box that has a 10-digit rotary switch and two arcade buttons to add and subtract.
One goal of the project was to have the counting box retain memory of the display while being powered off. The easiest way to do this is to write the display data to the ATmega’s EEPROM. This EEPROM is only rated for 100,000 write cycles (although in practice it’s much higher), so [Nathan] included a 24LC256 in a little spasm of over-engineering. All the electronics are laid out on perf board, and the case is constructed from bamboo that was laser cut by Ponoko. The quality of the case itself is fairly remarkable – we’re really impressed with the finish and the magnetic battery access door.
From experience, we know that playing with an HP-15C eventually leads to a broken calculator and having our Nintendo taken away. We’re really happy for [Nathan]’s son, and wish we had our own counting box at his age.
Why risk frostbite and altitude sickness when you can marvel at the view from atop your own mountain climbing game?
[Jeff] built this delightful piece which you can see in action after the break. he combined several very simple ideas and he did it really well. The climbers are both mechanical. They grip the mountain’s face (which is covered with of carpet) with a tack pointed downward on the end of each limb. Their motion is provided by two tiny servos that make up the body of the climber. The two potentiometers in each controller directly affect the movement of the top and bottom limbs. The game plays music during the contest, and precisely detects a winner by sensing when an arm comes in contact with the metal snow cap at the summit.
Obviously weight was an issue during the design process. After some hemming and hawing [Jeff] decided to tether the climbers in order to avoid rolling a battery into each. But he overcame the issue with weighted cable management on the inside of the mountain.
Continue reading “Head-to-head mountain climbing from the safety of your game room”
[Dino] is staying true to his goal of hacking one project every week. This time around, he’s working on a toy that will amuse and delight his cats. The project centers around a mouse house that has two holes where mice can stick their heads out. When they do, a little LED lamp illuminates their appearance in hopes to catch the eye of your lazy kitty.
The mechanism that automates this device is quite clever and reminds us of the most useless machine. That is, the armature that holds a mouse on either end actuates a limiting switch in the middle of the box when it moves to expose one of the mice. Each of those mice is attached with a rod, along side a leaf switch that makes the mouse retreat when boinked on the head by the cat.
It only takes [Dino] about six minutes to walk us through the build in the video after the break. What follows is a walk through of the wiring and some playtime with the family pets. Despite the intended purpose, it looks like the dog is much more interested than the cat. Either way, it’s a winner in our book.
Continue reading “Hacking for feline enjoyment”
Hackaday reader [Danukeru] sent us a video featuring a box-based robot with an interesting personality. The box is fairly simple and from the outside seems to consist only of a switch and an LED. When the switch is flipped however, the box comes to life.
When the box is activated, the lid opens, and a small arm reaches out to turn the switch off. We’ve seen that plenty of times, but this one turns out to be a little different. In the video, this process seems to repeat a couple dozen times before the robot gets angry and flips out. At first we thought that the end portion of the video was done with a bit of digital trickery, but after reviewing the creator’s blog, it looks like it could be legit. It is very hard to see the box’s innards in the video, but it does house a remote control car chassis that allows it to move around and spin out, as seen below.
It’s a pretty neat project, and if you can handle reading the creator’s site via Google translate, there is plenty of picture documentation of the build process for your perusal.
Continue reading “Don’t hit that switch!”
[Trav] was pondering virtual reality and decided it was no longer all that it was cracked up to be, so he created an experience in what he calls “Remote Reality”. While we have seen many installations over the years that allow people to remotely interact with objects across the globe, his Orbduino project consists of more than simply toggling lights on and off (though he’ll let you do that too).
In his house, he has set up a robotic playground of sorts that allows anyone who visits a chance to play around with the robotic arm he has installed there. The arm is situated in a pen filled with random objects which can be stacked and moved around. He also promises to show you something fun, provided you can guide the arm to pick up an object and hold it against the target positioned outside the pen.
He didn’t forget the obligatory remote light controls either. You can turn the overhead lights on and off, as well as control a multi-colored orb situated in the corner of the room. Most of the project’s interface is done with an Arduino Mega, which handles the robot arm interface, as well as messing with the light installations.
If you have some free time, swing by his site and give the robotic arm a try. It’s a fun little time waster that you will likely enjoy. Just make sure to take it easy on his web server!
A while back, [Dino] built an automatic ball launcher for his dogs, but he wanted to revise it to make it smaller and a bit more user-friendly. While watching an episode of “Prototype This”, he came across a great idea to improve his launcher, so off to the workshop he went.
He repurposed a power window motor from a car, and mounted it to some wood-reinforced aluminum sheeting in his garage. He added a piece of aluminum tubing to serve as a spring-loaded launch arm, which is drawn back by a small lever attached to the window motor.
When a ball is dropped onto a switch at the bottom of the launcher, the window motor starts turning, which pulls the launch arm back into place. Once the arm reaches the tipping point, the spring snaps it forward, launching the ball across the yard. The lever attached to the window motor eventually makes its way back under the launch arm, and is stopped by a switch that is also attached to the motor.
After the prototype was finished, he added some more wood to protect the mechanism from his dogs and vice versa. A hopper was added to the top of the structure to allow the dogs to load the launcher themselves, after a bit of training.
Now, some of you might wonder what is wrong with [Dino’s] arm. Truth be told, it works just fine. If you are a frequent Hack-a-Day visitor, you know that he spends plenty of time in the workshop, so this is an easy way to let the dogs entertain themselves until their owner is ready to play.
Check out the video embedded below for a demonstration of the launcher, as well as a detailed walkthrough of how the mechanism works.
Continue reading “Automatic ball launcher is for the dogs”