A DSLR Shutter Cable For Android

May 21, 2012 by Mike Szczys 4 Comments

Here’s a very easy way to trigger your DSLR camera using an Android device. It’s a similar method used with IR triggered cameras, in that all you need to do is assemble some simple hardware to plug into the headphone jack. The app that triggers the camera simply plays back a well crafted audio file to do so. The thing that this cable adds is the ability to use the focus feature, since the cable has two data lines.

The hardware is dead-simple. A pair of NPN transistors and a pair of resistors are hosted by this small chunk of strip board. The audio jack for Android uses left and right audio channels to drive the base of these transistors. On the camera side of things the transistors are pulling the focus, and shutter contacts to ground. Once this is covered with shrink tubing it’ll be pretty rugged, and ready to be thrown in your camera bag for use on short notice.

[Thanks Hannes]

Hacking IPod Headphone Controller For Use With Android

May 18, 2012 by Mike Szczys 5 Comments

[Buddhra] wanted to use a set of ear buds that also had a controller built into the wire. The headset he chose to go with is meant for use with iPod, but he figured it should be possible to make it work with Android too. He was right, and managed to alter the controller for Android use and still fit it into the original case.

He had already made a custom control module that has fast forward and rewind features and play/pause events. The signals used for the controls are based on resistive dividers. The play/pause button on the iLuv headset already worked, so he cracked the controller open to see why the forward and back buttons didn’t work. It turns out all he needed to do was add the right resistors to those buttons. Here you can almost see the 0603 surface mount packages he used to add a 220 Ohm resistor to the back button, and a 600 Ohm resistor to the forward switch.

Building Sensors For The Scratch Programming Language

May 17, 2012 by Mike Szczys 8 Comments

[Kevin Osborn] is making it a bit easier for young programmers to write programs that interact with the physical world. The device he’s holding in the picture is an Arduino based accelerometer and distance sensor meant for the Scratch language.

Scratch is a programming language developed at MIT. It has kids in mind, and focuses on graphical building blocks. This can make it quite a bit easier to introduce youngsters to programming concepts without the roadblocks and gotchas that come with learning syntax.

As you can see in the clip after the break, [Kevin’s] Arduino sketch includes hooks that automatically pull the accelerometer and distance data into the Scratch environment. We figure his example provides everything you need to get just about any type of sensor up and running, be it a magnetometer or LDR (both of which would make a nice burglar-alarm type project). Give it a try with your own hardware and see what you can accomplish.

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Self-Powered USB Host Mode On The HP Touchpad

May 16, 2012 by Mike Nathan 7 Comments

touchpad-usb-host-power

[ften] was having plenty of fun running Android on his HP Touchpad, but he soon discovered that the tablet’s micro USB port didn’t provide enough juice to his peripherals when running in host mode. He started digging around and found the perfect means of providing the extra power while maintaining the device’s stock appearance.

He pried the tablet apart and installed a small DC step up converter in an empty space located behind the Touchpad’s dummy SIM slot. After wiring the converter to the battery terminals, he installed a micro USB adapter in the empty slot, which fit perfectly after a bit of sanding.

He hacked together a USB Y-cable to pull power from his new USB jack, while retaining the existing data connection through the original USB interface. You can see the results of his work in the video below, and while [ften] hasn’t said how much his mod affects the Touchpad’s battery life, he has confirmed that it will still shut down gracefully once you inevitably sap the battery dry.

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Visible Kitteh Project Keeps Mice Out Of The House

April 21, 2012 by Brian Benchoff 28 Comments

[Aaron] and his wife have a wonderful cat that likes to contribute to the household by bringing field mice, shrews, and voles into the house as a ‘present.’ Obviously, this leads blood, fur, and viscera staining the carpet, and chasing around mortally wounded rodents isn’t [Aaron]’s idea of fun. To stop the cat from bringing small mammals into the house, [Aaron] is now preventing the cat from entering the house when it has an animal in its mouth.

[Aaron]’s project is inspired by this facial recognition cat door that refuses entry of all cats holding a small rodent in their mouth. To get his system working, [Aaron] started researching object recognition and built an Android app using the OpenCV libraries. To detect if his cat has a rodent in his mouth, [Aaron] is using Harr cascades – a proven object detection system that will detect and differentiate between a cat and a cat plus mouse.

Right now, the project is only about half done. [Aaron] is currently training his object recognition system, a process that can take days. Still, anything that keeps mouse guts out of the carpet is an awesome project in our books.

Android App Review: ADSdroid Gives You Every Datasheet, Ever

April 18, 2012 by Brian Benchoff 34 Comments

A few months ago when I reviewed the Android electronic reference app ElectroDroid, I made the offhand remark that a front end app for alldatasheet.com would be a killer mobile electronic reference app. [András Veres-Szentkirályi] accepted my challenge and built ADSdroid, the unofficial Android app for alldatasheet.com. You can check out my complete review after the break.

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Full Linux Distro On A Nook Color

April 17, 2012 by Mike Szczys 20 Comments

We should have included a footnote in the title. You can say that [Thomas Polasek] installed a full version of Arch Linux on his Nook Color, but there’s one caveat. It’s running on top of the Android kernel and his proof-of-concept uses a second computer to get it up and running. But there’s potential for that to change moving forward.

Unlike previous attempts to run a Linux distro on Android, this does away with using a VNC to show the desktop. [Thomas] is commandeering Android’s frame buffer so that it can be used by the X desktop without needing to set up display drivers. To start off he installed a ROM based on CM7. A couple of Android apps give him the functionality needed to get the Arch Linux distro running from the SD card. This is accomplished by tunneling into the tablet via SSH, and using the ‘chroot’ command to make it active. The hope is that this can somehow be automated by a script.

A female to female USB coupler was used to connect the keyboard and mouse to the Nook. It looks like LXDE would be useless without them; touch control is not yet implemented. Those shortcomings aside, everything seems to be running pretty fast in the video after the break.

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