Light polarization is an interesting phenomenon that is extremely useful in many situations… but human eyes are blind to detecting any polarization. Luckily, [David] has built a polarization-sensitive camera using a Raspberry Pi and a few off-the-shelf components that allows anyone to view polarization. [David] lists the applications as:
A polarimetric imager to detect invisible pollutants, locate landmines, identify cancerous tissues, and maybe even observe cloaked UFOs!
The build uses a standard Raspberry Pi 2 and a 5 megapixel camera which sits behind a software-controlled electro-optic polarization modulator that was scavenged from an auto-darkening welding mask. The mask is essentially a specialized LCD screen, which is easily electronically controlled. [David] whipped up some scripts on the Pi that control the screen, which is how the camera is able to view various polarizations of light. Since the polarization modulator is software-controlled, light from essentially any angle can be analyzed in any way via the computer.
There is a huge amount of information about this project on the project site, as well as on the project’s official blog. There have been other projects that use polarized light for specific applications, but this is the first we’ve seen of a software-controlled polarizing camera intended for general use that could be made by pretty much anyone.
You’ve built the perfect robotic arm. How do you drive it? If you are [angrymop] you interface a 3D mouse from 3DConnexion via a few microcontroller boards. The Spacenavigator mouse is a staple anywhere professional CAD people are working, and it looks like it is a natural fit for a robot arm.
According to [angrymop], the Raspberry Pi can read the mouse’s commands via /dev/hidraw (that’s the raw human interface device). Each motion generates two lines of output. Each line has a unique identifying byte and values corresponding to the axis positions.
The Raspberry Pi then uses an SPI interface to talk to an ARM microcontroller and that drives the servos. The arm (the robot arm, not the processor) itself is well done, made from Lego Technic parts and common RC servos. Not that this is the most amazing thing we’ve ever seen built from Technic, but it is still pretty impressive.
You have to wonder if other 3D controllers might be useful for controlling robot arms or how the Spacenavigator would do controlling a bigger, more capable arm. Then again, maybe this arm would be the right size to build something inspired by Escher.
Continue reading “3D Mouse Drives Robot Arm”
Since 1998 we’ve been privileged to partake in an arcade game known as Dance Dance Revolution, but before that, way back in the 70’s, was the Simon game. It’s essentially a memory game that asks the player to remember a series of lights and sounds. [Uberdam] decided to get the best of both worlds and mixed the two together creating this giant foot controlled Simon game. (English translation.)
The wood platform that serves as the base of the project was fitted with four capacitive sensors, each one representing a “color” on the Simon game. When a player stomps on a color, a capacitive sensor sends a signal to a relay which in turn notifies the Raspberry Pi brain of the input. The Pi also takes care of showing the player the sequence of colored squares that must be stepped on, and keeps track of a player’s progress on a projector.
This is a pretty good way of showing how a small, tiny computer like the Raspberry Pi can have applications in niche environments while also being a pretty fun game. We all remember Simon as being frustrating, and we can only imagine how jumping around on a wooden box would make it even more exciting. Now, who can build a robot that can beat this version of Simon?
Continue reading “DDR-ing a Simon Game with a Raspberry Pi”
Many major companies (Intel, Oracle, Atmel, and IBM, for example) are competing to be the standard interconnect fabric for the Internet of Things. As a developer, it is hard to cut through the marketing hype and decide which platform is the best for you and your application. Luckily, there’s a plethora of projects on the web that showcase these frameworks. These project sites are an easy way to evaluate the strengths and weaknesses of IoT frameworks in practical applications without having to develop prototypes yourself.
[diyhacking], for example, posted a demo of using IBM’s Bluemix along with a Raspberry Pi, to do some simple home automation tasks. The project hardware is modest, using a PIR motion sensor and a relay to control an AC load. However, that’s good because it lets you focus on the Bluemix tools. The example client and server software is less than 200 lines of Python.
Bluemix looks like it has good integration with the Raspberry Pi and features a simulator so you can work without real hardware for development. Bluemix does offer a free plan (with limits), but the fee options may be a turn off to some IoT hackers.
Continue reading “Another IoT Platform in the (Blue)Mix”
This one’s crazy… literally one electronic device is talking to another. In spoken English. And it works.
We’ve covered several hacks for the Amazon Echo, but some might be surprised to learn that there is another piece of interesting hardware that comes along with it – a remote control. Wire in a Raspberry Pi to it, and you’ve given yourself a way to automate control of the Echo without ever taking the Echo itself apart. [Gamaral] did just this and gave his Echo some significantly enhanced capabilities.
He started off by identifying the power rails of the remote. Then he wires in a 3.3v voltage regulator and uses a 100 ohm resistor as a voltage divider to bring it down to the 1.8 volt logic level used by the Echo remote. A single wire runs from the Raspi GPIO to one of the tactile switches on the controller.
For software, the Raspi is running RPi buildroot with Espeak and a cron scheduler compiled in. This allows him to send commands to the Echo which makes it say just about anything he wants. But any voice commands accepted by the Echo should work. If you want to go outside of those boundaries check out the method of spoofing WeMo devices we saw the other day.
Be sure to check out the [gamaral’s] entertaining video below to see the hack in action.
Continue reading “Hacking Amazon Echo Through Its Remote”
FlightAware is the premier site for live, real-time tracking of aircraft around the world, and for the last year or so, Raspberry Pi owners have been contributing to the FlightAware network by detecting aircraft flying overhead and sending that data to the FlightAware servers.
Until now, these volunteers have used Raspis and software defined radio modules to listen in on ADS-B messages transmitted from aircraft. With FlightAware’s new update to PiAware, their Raspberry Pi flight tracking software, Mode S transponders can also be detected and added to the FlightAware network.
Last year, FlightAware announced anyone with a Raspberry Pi, a software defined radio module, and an Internet connection would earn a free FlightAware enterprise account for listening to ADS-B transmitters flying overhead and sending that information to the FlightAware servers. ADS-B is a relatively new requirement for aviators that transmits the plane’s identification, GPS coordinates, altitude, and speed to controllers and anyone else who would like to know who’s flying overhead.
Mode S transponders, on the other hand, are older technology that simply transmits the call sign of an aircraft. There’s no GPS information or altitude information transmitted, but through some clever multilateration in the new PiAware release these transponders and planes can now be tracked.
To get the location of these transponders, at least three other PiAware boxes must receive a signal from a Mode S transponder. These signals, along with a timestamp of when they were received are then sent to the FlightAware servers where the location of a transponder can be determined.
The end result of this update is that FlightAware can now track twice as many aircraft around the world, all with a simple software update. It’s one of the most successful applications of crowdsourced software defined radio modules, and if you’d like to get in on the action, the FlightAware team put together a bulk order of ADS-B antennas.
Unless you live way up in Canada, it’s not very likely that those gorgeous coronal mass ejections will collide with the atmosphere above your home. If they do, it’s a rare occurrence you wouldn’t want to miss. This is why [James] devised of a special alarm that would notify him when the Northern Lights may be visible in his neck of the woods. And what’s a better aurora alarm than a simulated aurora light show for your room?
[James] uses a Raspberry Pi to check data from Aurora Watch UK at Lancaster University for local activity. If the forecast reads that there may be some light above his home town in northern England, it triggers a NeoPixel LED strip to scroll through the color values of an actual aurora PNG image. This produces the same sporadic shifting of colors for a proximal ambient indoor lighting effect… though slightly less dramatic than the real thing. You can take a look at his Python script on github if you feel inspired.
Continue reading “LED Strip Notifies You Of The Light Show You’re Missing Outside”