Turntable Sequencer Scratches With Coins

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[tvst] has an interesting take on a sequencer. His design uses coins on a turn table to trigger midi events in a loop. There are four tracks available, each having its own sensor above the spinning platform. The sensors consist of an IR transmitter and receiver setup as a voltage divider. When something passes below the IR transmitter and reflects the infrared waves back up to the receiver, the output of the sensor moves to digital high. The four sensors are connected to an Arduino which is used in conjunction with ttymidi, which converts the Arduino data into midi events.

We like projects that provide a more tangible interface for the user. Coins work well for this setup. They reflect infrared enough to trigger the sensors, and they’re easy to pick up and move without upsetting the rest of the tracks. It would be great if this could be expanded to differentiate between coins (pennies versus dimes, etc.) in order to increase the resolution from four different events to eight or more. Check out the video after the break. Continue reading “Turntable Sequencer Scratches With Coins”

It Has Blades: Dyson’s Little White Lie

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‘There’s a sucker born every minute” -P.T. Barnum

This morning we’ve been having a heated discussion at the Hack a Day offices (read: legion of doom) over Dyson’s new offering, a “bladeless fan”. At first this seemed extremely exciting, but how is the air being moved? We were hoping for a device operating via ionic wind but that’s simply not the case. Some of us think the bladeless claim is an outright lie, others understand it from a marketing stance, but we all agree: a fan with blades is still moving the air.

Dyson’s own information page states that “an energy efficient brushless motor” draws the air in with similar technology used in “superchargers and jet engines”, both of which use blades! The fan blades are in the base of this unit, they take in air and blow it out the ring. Just because you can’t see a fan, can we call our computers bladeless, or an air conditioner bladeless?

Enter the P.T. Barnum reference. Known as a man who could sell anything, his legacy lives on in the Dyson corporation. At 200 british pounds (~$320) for a ten inch desk fan, what are you getting that’s better than a traditional fan?  The design supposedly amplifies the air movement fifteen times, but we’re skeptical about that figure as there’s no energy-saving claim to go along with such an incredible power boost. One thing is certain, you will NOT get a fan without blades for your sterling… just one with hidden blades plus a huge marketing campaign.

[Thanks Gareth]

DASH: Clever Construction And Resilience In Robotics

[youtube=http://www.youtube.com/watch?v=LsTKAtBBkfU]

Behold the Dynamic Autonomous Sprawled Hexapod (DASH). The video above was presented at the 2009 International Conference on Intelligent Robots and Systems. In it we see the toils of a team from UC Berkeley’s Biomimetic Millisystems Lab. They’ve developed a robot propulsion system that mimics some of the best aspects of cockroaches and other insect bodies: speed, economy of motion, ability to survive large falls without damage, and the capability to traverse obstacles. Let’s take a look at how they put this together after the break. Continue reading “DASH: Clever Construction And Resilience In Robotics”

Jamin’ To Bach, Commodore 64 Style

[youtube=http://www.youtube.com/watch?v=MOhzkWZHBfM]

[thrashbarg] missed the sounds of the Commodore 64 and longed to hear the great masters in 8-bit glory. To get his fix, he created a midi device using the original Sound Interface Device from those long-dead systems. He’s interfaced the MOS6581 SID with an Atmel AVR ATmega8 microcontroller. The receiving pin for the AVR’s UART is used as a MIDI-IN connection, with the microcontroller converting midi data into the proper sound generation specs for the SID. The result is the 10 minutes of [Bach]’s Brandenburg Concerto heard in the embedded video above.

We have no idea where he picked up this obsolete chip, but if you want to give this a try, perhaps you’ll have some luck emulating the MOS6581 by using another ATmega8.

OLPC Pedal Power

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A One Laptop Per Child group out of Afghanistan have come up with a way to power the XO using pedals. The system interfaces a set of pedals with the Freeplay hand-crank charger, freeing up both hands for typing. Although not as compact, using both legs makes power generation much easier. Apparently a child as young as 3rd grade is able to pedal this well enough to power the computer in real time.

We just hope this contraption is used for learning and betterment, and not in a pedal-for-porn scenario.

[via Gizmodo]

Halloween Props: Flying Crank Ghost

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[Jake’s] projects have become regular features here on Hack a Day. He keeps the Halloween hack-fest rolling with his Flying Crank Ghost. For the ghost he used a store-bought skull but sculpted some hands himself out of Styrofoam. The body is fashioned from coat hangers with a bit of creepy fabric draped over the hole thing to complete the look.

He added some very convincing motion to the ghoul using a salvaged microwave turntable motor. The motor is mounted in the center of a two crossed boards, and has an armature attached to it. Three strands of monofilament attach to the end of the armature, run through eyelets on the ends of the crossed boards, then attach to the head, and each arm. When the motor is turned on, the armature turns, moving the head and hands up and down at different rates. Take a look at the embedded video after the break to see the final product.

[Jake] does mention that the motor he used is a bit underpowered. We figure this only needs to hold up for one night, so dig through your junk bin and see if you can throw one of these together in a few hours.

Continue reading “Halloween Props: Flying Crank Ghost”