Paper Accelerometers For Pennies In The Works

Cheap paper accelerometers? Put us down for a dozen to start. They’re not quite ready for mass production yet but it looks like they’re on the way.

[George Whitesides] led a team to develop the new technology that uses simple manufacturing methods to produce the sensor seen above. Graphite and silver inks were screen printed onto heavy paper. The single limb sticking out from the body of the sensor is a separate piece of paper that bends the carbon area when force is applied. This changes the carbon’s resistance which is measured using a Wheatstone bridge constructed by gluing resistors to the device.

It sounds unsophisticated compared to most of the accelerometer modules we’re used to, but if you need a sensor that detects sudden motion this sounds like the perfect part. Now who wants to be the first person to replicate this in their basement?

[Thanks Fabien]

Imploding Vacuum Tubes For Science

The researchers at Brookhaven National Laboratory are looking for a way to harden photomultiplier tubes. In order to make a more durable tube the researchers decided it would be a good idea to first observe how the tubes are failing. So they got their hands on an old torpedo test bay and smashed some bulbs inside of it. Check in after the break for some high fps bulb smashing.

Photomultiplier tubes are used in massive quantities to detect the highly elusive neutrino particle. The problem is when you have 50,000 photomultipliers submerged in pressurized water the the collapse of just a single bulb can cause a shock wave of destruction. This is what happened in japan in 2001 when a maintenance worker unknowingly compromised a single bulb in a 11,000 bulb array. When the tank was repressurized that single compromised bulb caused them to lose 7,000 more.

[via wired]

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What Development Board To Use?

Here at Hackaday, we see microcontroller based projects in all states of completion. Sometimes it makes the most sense to design systems from the ground up, and other times when simplicity or a quick project completion is desired, pre-built system boards are a better choice. We have compiled a list of boards that we commonly see in your submitted projects, split up by price range and with a little detail for reference.

After reading our list, sound off in the comments or on this forum post, and we may include your board in a follow-up guide at a later date. We will also be giving away 10 Hackaday stickers to the most insightful, the most original, and most useful advice given on the forum, so if you haven’t registered yet, now would be a perfect time. Winners of the sticker giveaway will be selected from the forum thread, and the final decision for prizes will be judged by the wit and whim of the Hackaday writing team. More prize details to follow in the thread. Read on for our guide based on past project submissions.

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The OpenServo Project

When it comes to using servos in projects, there is a definite distinction between the cheap ones and the expensive high power and precision models. The OpenServo project gives you a couple options for enhancing your servo experience. By replacing the control board with a new one based on a familiar microcontroller, a whole new set of features can be attained. For those of you out there with a need for servos like these, you can buy the pre-built replacement board (unfortunately sold out right now), or build your own from the provided schematic, BOM, and source code.

Lessons In Electric Circuits

Are you looking for a good source of information to get started into making and hacking electric circuits? We would like to refer you to Lessons in Electric Circuits. Even if you have good knowledge of electronics, this is another tool you can use. The book is a work in progress and will have some incomplete and pending areas, but the basic theory parts to get started are all there. It has six volumes: DC, AC, Semiconductors, Digital, Reference, and Experiments. The DC and AC volumes are the most complete. If your eyes are already glazing over thinking you already know all of this stuff, then the most interesting volume for you may be the Experiments, which contains a number of sample circuits like transistor amplifiers and 555 timer circuits. The best part of this book it that it is free, but as with most free things, you can make it better by contributing.

Via Adafruit Industries.

Beginner Concepts: LEDs And Laws

Adafruit has a new LED tutorial for people wanting to get started with electronics. It is full of useful diagrams, pictures, and quizzes to help make sure you are understanding the concepts. This is the real basic stuff here: LEDs, resistors, and the laws from Kirchhoff, and Ohm. It starts out explaining the parts of an LED. Then variations of LEDs: illumination versus indication, clear versus diffused, brightness, color, and size. The mass of the tutorial covers how and why an LED’s brightness can be changed by a resistor and why a resistor is needed to keep an LED from burning out. Such as how Kirchhoff’s Voltage Law works with Ohm’s Law to help you determine the proper resistor for an LED. If you found useful the other beginner concepts posts about Analog Circuits and Electronics basics from the Giz, you should find this tutorial to be useful.

Making Point Contact Transistors

[youtube=http://www.youtube.com/watch?v=vmotkjMSKnI&w=470]

[Jeri Ellsworth] is back at it again. We seem to cover her work a lot here. Her latest video above covers how she created a point contact transistor from a 1N34 germanium cat whisker diode. After opening the glass casing on the diode, she uses sharpened phosphor bronze metal from common electrical connectors as the collector and emitter. A 330 microfarad capacitor charged to 20 volts and then discharged though a 680 ohm resistor to the base and collector leads forms the collector region. Her test jig is a simple oscillator circuit such that a properly formed transistor will start the circuit oscillating and make and audible sound. We look forward to more esoteric knowledge of electronic devices being brought to our attention.