Flash controller works with point and shoot cameras

Needless to say, there’s a world of difference between the expensive DSLR cameras professional photographers use and the point-and-shoot models carried by commoners. One such difference is the ability to use slave flashes – a second flash set off to the side of the subject for better illumination. Most of these slave flash units are triggered when they see a bright light, or when the on-camera flash goes off. Point and shoot models usually have a ‘pre-flash’ that cause a slave flash to trigger prematurely. [Kerry] built a really neat slave flash that is able to work with these point-and-shoot cameras, and is pretty easy to build as well.

There are two options when it comes to building a flash that can work with a point-and-shoot: First, measure the time between the pre-flash and real flash, and then simply delay the slave flash. This option has a few problems. Even when [Kerry] tested this technique on the same camera, the delay between the flashes were never consistant.

The second option is to simply ignore the pre flash and synchronize with the main flash. This is a little harder, but if done right this technique is nearly foolproof.

[Kerry] ended up building a small circuit out of a 556 timer chip and an LM339n comparator that turns itself ‘on’ just a little bit after it sees the pre flash. From there, the device looks for the main flash and triggers itself whenever it sees another bright source of light.

The finished product works beautifully, and is simple enough for just about anyone to build on a piece of perf board.

Making a touchless vibrator with reverse engineering

Here’s one for the ladies (and men, we guess) out there.

[Beth] recently bought a LELO Lyla vibrator for herself, but found operating this wireless vibrator to be an exercise in mood-killing awkwardness. Wanting a more natural interface, she decided to reverse engineer a remote control vibrator. Here’s a cache; [Beth]‘s blog has been up and down all day.

The LELO Lyla comes with a wireless control in the form of a neon pink remote. [Beth] thought this remote was a little clunky and felt like programming a VCR – something she doesn’t like in a sex toy. With the goal of improving this remote and allowing for a better user experience, [Beth] tore down this remote and began to build her own.

The new vibrator remote would have to be touchless – there’s nothing that kills the mood faster than mashing buttons. By using ultrasonic sensors, [Beth] would be able to control the intensity of her vibrator by simply waving her hand; a much more natural interface. With the control interface out of the way, the only thing left to do was to figure out how to control the business end of the vibrator.

The remote for a stock LELO Lyla comes with a MSP430 microcontroller and a 2.4 GHz CC2500 radio controlled over an SPI interface. Instead of disassembling the microcontroller and figuring out the firmware from scratch, [Beth] decided to sniff the SPI bus and make her own controller.

After attaching some 0.1″ headers to the stock remote and soldering a few wires to the microcontroller, [Beth] captured the SPI data with a Propeller dev board. By streaming the SPI traffic to a terminal, she was able to figure out exactly how the remote works and set out on building her own.

The new remote was built out of an Arduino Pro Mini, ultrasonic sensor, CC2500 radio and a four digit 7-segment display. After printing an enclosure, [Beth] had a very easy to use, hands free vibrator.

In the video after the break you can see [Beth]‘s vibrator in action. She’s still looking for a few more ways to improve it such as predicting the movements of her hand with a phase-locked loop, but for now we’ll just tip our hat to [Beth] for a very awesome hack.

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Beating a plowshare into an AK-47

[Boris] must have been a little bored over Thanksgiving. We’re guessing that’s the case; why else would he build an AK-47 out of a common garden shovel?

After buying an old shovel from an antique barn in Vermont, [Boris] cut off the handle an attached it to an old Bulgarian AK he had just lying around. The new stock proved to be very comfortable, and not wanting to waste the iron in the shovel head, decided to make an AK out of the remainder of his purchase.

After tossing the shovel head into the furnace and pounding it flat, [Boris] had a respectable piece of metal to construct an AK receiver from. A bit of plasma cutting, grinding, and drilling turned this former shovel into a future gun, and with the help of a blank barrel the shovel became an AK receiver that is twice as thick and twice as heavy as a ‘normal’ AK receiver. Yes, [Boris]‘s new gun is even more indestructible than a stock AK – something that really shouldn’t be possible.

In the end, [Boris] spent $2 on a shovel, $30 on a barrel, and $200 on a Romanian AK kit. The result is an actual, working gun that is legal for him to own (but not sell – see the comments for that discussion).