Build Your Own Class AB Audio Amplifier

[Dino Segovis] wrote in to tell us about his “hack”, making an AB Audio Amplifier. The advantage of this particular amp is that the transistors never turn off, which would cause distortion. A full schematic is given in the article as well as a parts list. A complete “bill of materials” makes any circuit building project easier, especially for the beginner.

Although this is by no means a new circuit design, (a similar setup is used in car audio equipment) [Dino] does a great job of explaining how things work in the article itself and in the video after the break. He also gives some great tips about transferring your drawn circuit to a breadboard in a neat and organized way at around 5:00 in the video. Continue reading “Build Your Own Class AB Audio Amplifier”

Obama-1 Desk Spy Satellite Aims For High Approval Ratings

This miniature “spy satellite” may not gain the ire of the Chinese People’s Army, but it will certainly look rad on your desk.  Besides looking cool, this “satellite” is able to transmit video up to 300 feet away and has sun tracking solar panels for battery recharging. Additionally, it has a LED “thruster” and speakers.

One cool thing about this build is that the body was made out of a lamp from Goodwill. Recycled/thrift store enclosures always make a good addition to your project as they won’t break the bank. Additionally, they may yield some other bonus parts when taken apart. In this case, the lamp fit into the project scope perfectly, but anyone trying to duplicate it might not be so lucky.

Creative use of other household materials rounds out this build, with solar panels taken off home garden lights, and part of a nose hair trimmer used as the “thruster” body. This well-build project is a great example of how to convert household items into something totally different and unique.

[youtube http://www.youtube.com/watch?v=pGqTmnSP71U&w=470&h=349%5D

An “Earthcore” Hexapod With Minimal Mechanical Parts

Although hexapod robots have been featured on [HAD] many times, this one features a really cool minimalistic design. With few mechanical parts to support the three servos, the “Earthcore Hexapod Robot” has a unique gait, tending to quickly slide the driving legs rather than picking the whole robot up. Although it would probably have trouble on rough terrain, for use on a smooth floor or counter, this ‘bot is perfectly suited.  Check out the video of it after the break.

Another thing that really stands out on this bot is the blue LED “eyes” and it’s tubing “hat.”  The “hat” hides the wiring for the three servos, while most of the circuitry looks to be in between the eyes. The main controller is a PICAXE 18M2 micro-controller. 3 AAA batteries seen behind the tubing power the unit.

As for the name “Earthcore”, it’s based on a book by [Scott Sigler]. If there is a movie version in the works, we hope he calls [onefivefour] to help with the special effects! Continue reading “An “Earthcore” Hexapod With Minimal Mechanical Parts”

A Robotic Turtle Platform To Buy Or Build

This electric turtle bot instructable describes a fairly simple turtle-style robot meant to be laser cut out of acrylic (although other materials such as aluminum, MDF, or polycarbonate should work just as well). This frame is also optionally for sale, which should appeal to those that would like a mechanical robotics platform to play with, but don’t have access to machine tools. The build instructions include a detailed bill of materials which should come in handy.

As displayed in the video after the break, the robot uses a sonar sensor to navigate. This sensor is set up on a servo in order to scan the terrain, and, depending on how it’s programmed, hopefully avoid obstacles. As of when the video was taken, the little robot appears to sense an obstacle then scan with the servo left and right to see what the best way to turn is.

[youtube http://www.youtube.com/watch?v=vA_kIY3MvTE&w=470&h=349%5D

If this little turtle robot doesn’t have enough power for your taste, check out this autonomous ATV sentry.

Programming The Kinect To Work With Android

The Kinect has been hacked for many purposes, but this Android implementation tutorial is the first we’ve heard of it being used on a mobile phone platform. Although not a finished product at this point, [Raymond’s] tutorial is a good starting point for those wanting to experiment with fusing these two technologies.

The Kinect programming for this tutorial has been done with the Tegra Ventana development kit for Android 3.0. An Ubuntu-Linux installation is used, but this technique should be portable to any Linux system according to the author.

The procedure given is pretty straightforward, and the author even provides an example of the results in a video after the break. It’s interesting to note that, when connected, the Kinect is seen as two devices, “Xbox NUI Camera” and “Xbox NUI audio”. We look forward to new hacks to come out for this device, possibly using this set of tools. Continue reading “Programming The Kinect To Work With Android”

The DIY Nuclear Reactor

“Wednesday, I was arrested and sent to jail,” is what your blog might say if you decide to try and duplicate this project.  You may, however, be fortunate to be still writing your blog, as ATTEMPTING TO BUILD YOUR OWN REACTOR can be quite dangerous. That’s what [Richard] did using household items such as clock fingers for Radium, and smoke detectors for Americium. After the radioactive elements were separated from their household “containers” and melted down, they created a small explosion on his stove.

This attempted experiment is based on one that was done by [David Hahn], AKA, “The Nuclear Boyscout”, in order to obtain his nuclear energy badge.  For what it’s worth, [David] did attain the rank of Eagle Scout, however, he turned his parent’s house into a Superfund EPA cleanup site in the process.

The video after the break describes the process of making a reactor from household materials. This video may be entertaining, but duplicating it is not recommended (and would be somewhat expensive). Continue reading “The DIY Nuclear Reactor”

The Lego Synchro Drive

[M-byte] wrote in to tell us about the Lego Synchro Drive. Although not a new hack, this autonomous vehicle is quite amazing in it’s simplicity.  Using only one motor turning at a constant speed, this device is able to navigate obstacles by simply turning.

As [m-byte] was quick to point out, this is a simple task using modern electronics, but this drive is made using only Lego Technic parts. The machine’s motion is quite pleasing. When it hits an obstacle, the outer rotating ring stops, allowing the casters on the bottom to switch direction. One could see this invention coming out of Leonardo da Vinci’s notebook (minus the Legos).

Check out either of the embedded videos after the break to see this device in action. If you’d like to build one yourself, follow this link for very well illustrated directions. Continue reading “The Lego Synchro Drive”