This 5kV Induction Gun can shoot aluminum rings with some intense force. I have seen flying ring toys before which fly nice and straight. I wonder if the ring design is better than the typical bullet shaped projectiles we see on most of these guns.

"First portable induction accelerator in Russia. Capacitor energy 500j 5kV voltage, ring speed about 200m/s "

One way to learn lots about a protocol is by implementing a bit banged version. Openschemes shares with us his experimentation with the Arduino and the FT232 chip.

"We’ve been considering the synchronous bit bang mode of the FT232R for an upcoming project. The first steps towards something like this are always to build up a little debug board or test bench that can be used for debug and tweaking while the real boards are in fab. Luckily for us, the Arduino board contains an FT232R ripe for the hacking. For most users, all their dreams are fufilled by avrdude-jtag, which will allow them to reprogram the bootloader on the Arduino Atmega. As you may know, four of the FT232R’s GPIO pins are brought out to an unpopulated header on the Arduino board. The first (and easiest) job is to solder in a set of header pins for future connections."

Limitless Boredom has designed his own version of the Keepon Robot. There have been other Keepon clones out there but I must say that this one made with helicopter RC parts works quite good.

Thanks Ruyck.

PJMonty from SoCalHalloween sure knows how to rig up some great animatronics! The bird and talking skull are funny and spooky at the same time! This project was entered in the Halloween Project Contest, which by the way there is still time to enter.

Via: HG Forum

"The electronics consist of two custom circuit boards I designed. The bottom one (most of which is obscured) contains the micro-controller and memory. It talks to the host PC via a serial port and has animation moves streamed to it on the fly. The top board has another micro-controller and is responsible for handling the time critical work of controlling the actual RC servos. It also has some interface circuitry on it for things like the LCD. Partially visible on the right is the power supply which powers both the circuitry and the servos."

SoCalHalloween - "Small Candy" from SoCalHalloween on Vimeo.

Piezoelectric elements can be used to make sound or detect sound. Steve Hoefer has made a Knock Lock, which is a device that can listen to knocks on the door. If the sequence of knocks is the same as the recorded knock sequence it unlocks the deadbolt on the door. Steve was the guy who also made the Dice Reading Machine.

Via: Zedomax

"While working on another project I ran across the Arduino knock sensor tutorial. Sensing a single knock is a great little project for learning about microcontrollers, but what about sensing specific knocks? Seeeeecret knocks? And if we could detect a secret knock, shouldn’t it unlock a door? If you can’t tell by looking this was cobbled together from spare stuff around the lab, it’s not much more than a piezo speaker, a tiny gear reduction motor, and an Arduino. And PVC pipe."

AnotherCoilGun has been hard at work making his LED control board even smaller! His other tiny version looks huge in comparison.

Mitch Schoch from SimpleVoice.com built an interesting 4 axis DIY Foam Cutting CNC Machine. It has lots of control since all 4 motors can be driven independently. His design is modular, he has used phone jacks and 24 gauge phone cable to provide power the motors. Everything was purchased from the local hardware store so there are no exotic parts in the unit. From the video he looks to be using standard threaded rod and some big drawer slides to provide smooth motion with the use of the stepper motors.