My What A Large Capacitor Bank You Have

[Daniel Eindhoven] put together this 11,344 Joule capacitor bank that he says would be perfect for weapons such as a rail gun, coil gun, or electrothermal-chemical gun. He machined a couple of aluminum plates to act as a positive and negative bus. The two are separated by a denuded sheet of PCB (making us wonder how he got the copper to peel off like that). Once charged there’s the little problem of how to discharge the system without getting bit, which [Daniel] solved by building a pneumatic switch. We didn’t find the test-fire footage very interesting but we did embed the demonstration of his switch after the break.

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Building A Remote Control

Here’s a homebrew remote control that [Jad Berro] is developing. He’s using a tank robot to test it out but eventually he plans to use it to control an RC plane thanks the 434 MHz wireless module inside. There’s no shortage of input, with two analog sticks from a PlayStation controller, several momentary push buttons, and some toggle switches. Although it’s not shown in the picture above there is also a 16×2 character display that serves as part of the interface. With a navigable menu the only limit to what you can do is the programming space available on the ATmega168 that inhabits the homemade Arduino board at the heart of the system. It certainly would give the robot remote from Friday a run for its money.

Arm Mounted Light Cannon; Villains Beware

In a hack worthy of the flick Kick Ass, [Chein] built this arm-mounted light weapon. The lamp in the palm of your hand has a ring of LEDs for a nice glowing effect, but the real story is the xenon bulb at its center. The flash capacitor and charge circuit from a disposable camera are used to step up the battery voltage to 330V for an intense and slightly blinding discharge. The charging is started when you press a button on the back of the hand harness, with the flash coming when one of your fingers touches a conveniently positioned trigger. Check it out after the break.

This non-lethal weapon makes for a nice alternative to the dangers involve in playing with fire.

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Making Glow Sticks At Home


Even if you have no interest in making these yourself, you might enjoy this educational instructable about making your own glow sticks. Comprised of a very short list of chemicals, all available online, the process is fairly simple. If you’re feeling like you want to take on a little more complicated chemistry project, you can also make the TCPO component your self, possibly saving some money as the individual components are cheaper than the final product. As they note, it is just cheaper and easier to buy a glow stick, unless you are making mass quantities.

Servo Controller Board

This board is [Eric Seifert’s] venture into working with AVR microcontrollers. He has worked with PIC microcontrollers in the past and used the goal of developing a servo controller board as his motivation to try the grass on the other side of the fence. He found he likes the AVR line for its ease of development under Linux, a feature we also appreciate. What he ended up with is a tiny board that controls up to eight servo motors. If you’ve got a project that is spilling over with servo-controlled limbs, maybe this will save you some development time.