PiNoculars – A Farseeing Pi Camera

The Raspberry Pi camera provides a 5 megapixel resolution with still images of up to 2592 x 1944 and multiple video modes including 2592 x 1944 at 15 frames per second. With it being mounted on a small board it is ideal for using in hacks. [Josh Williams] mounted the camera on the lens of binoculars to capture some startling images, including this squirrel.

The camera is installed on a custom, laser cut mount that fastens to one eyepiece of the binoculars. The Pi itself is mounted above the binoculars. An LCD touch screen from Adafruit allows [Josh] to select the image and adjust the focus. Snapping pictures is done using either the touch screen or switches that come with the screen.

The Instructable [Josh] wrote is extremely detailed and includes two different ways of mounting the Pi on the binoculars. The quick and dirty method just straps on with tape. The highly engineered method delves into Inkscape to design a plywood mount that is laser cut. For portable operation, [Josh] uses one of the ubiquitous battery packs meant for USB charging.

Basic setup of the Pi and camera are in a video after the break.

 

Filed under: digital cameras hacks, Raspberry Pi, video hacks

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Nixie Tubes Adorn Steampunk Solar Power Meter

The appeal of adding Nixie tube displays to a project seems to know no end. First it was Nixie clocks, now it’s Nixie power meters, with the latest addition being this Nixie-Steampunk hybrid solar power monitor.

We’re suckers for a project with a vintage look, and this one pushes all the buttons. Built on commission for a solar power company CEO’s office, [Paul Parry]’s build is based on a Depression-era Metropolitan-Vickers combined voltmeter and ammeter. The huge meters with mirrored scales and the rich wood of the case – our guess is that it’s mahogany – made a great starting point, and after some careful hole drilling, nine IN-18 Nixies were sprouting from the case. A strip of RGB LEDs below decks added the requisite backlighting of the envelopes, and a Raspberry Pi was enlisted to interpret data from the company’s solar farm and drive the tubes and the meters. The project was capped off with a new finish on the case and a couple of fancy brass plaques.

[Paul] sent us the tip for his build after seeing the last power meter we covered, and we have to say they’re both great looking and functional projects. Keep the Nixie projects coming!

Filed under: green hacks, Raspberry Pi

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Raspberry Pi Zero – Turning the Pi into a USB Gadget, over USB

[gbaman] has figured out a simpler way to program the new Raspberry Pi Zero over USB without modifying the board. Why is this useful? One example which appealed to us was setting the Zero’s USB port up as a mass storage device. Imagine plugging in your Pi powered robot, dragging and dropping a Python script into the mass storage device that shows up, and pressing a button on the robot to run the new script. Pretty fancy for $5.00.

You can get the PI to emulate a whole range of devices from a USB MIDI controller to a simple USB serial interface. We’re excited to see what uses people come up with. Unfortunately the Pi Zero is still out of stock most everywhere as we wait for the next production run to finish. Though if you’ve got one, why not check out a few of our thoughts and experiences with the device!

[gbaman] based his work off the work done by [Dave-0] and others over at the Raspberry Pi forums. [LadyAda] also has a version of this hack, which we covered, that involves soldering a header to the pi and using a UART adapter.

[via Hacker News]

Filed under: Raspberry Pi

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Ten Mile Raspberry Pi WiFi (with a Catch)

How would you like to have a WiFi connection that covers 10 miles? Or how about an even wider network made up of a mesh of multiple nodes? It is possible, but there is a catch: you probably need a ham radio license to do it (at least, you do in the United States).

What makes it possible is the realization that conventional WiFi channels 1-6 are inside an existing US ham band. That means (if you are a ham) you can elect to use FCC part 97 rules instead of part 15 that governs WiFi routers. That means you can use more power and–even more importantly–better antennas to get greater range.

Traditionally, hams have used custom firmware for Netgear routers or Ubiquiti hardware. However, [WZ0W] recently posted his experience using Raspberry Pi boards as mesh nodes. The code (which also works with some other single board computers) is available on GitHub (with details on the project blog). [WZ0W] points out that, unlike using a consumer router, using a Pi provides a reasonably powerful computer for hosting services as well as hosting the network.

There is a video tour of the software in the video below. If you aren’t licensed, you may still be able to use the mesh network firmware, but you’ll have to stick to the stock radios and antennas. If you are not in the US, your laws may be different, so be sure you understand the laws in your jurisdiction.

If you just want a mesh network, there are other options. You can even rip off a conference badge design if you like.

Filed under: Network Hacks, Raspberry Pi, wireless hacks

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Raspberry Pi + Wolfram Data Drop

When you think of Mathematica and Wolfram, you probably think high-power number crunching. You might not think embedded systems. Wolfram runs on the Raspberry Pi, however, and there is a recent video (below) showing a Raspberry Pi, controlling I/O devices, and interacting with the Web using Wolfram data drop.

The second video, below, shows some older example projects including a simple home alarm with a PIR sensor. Not the kind of thing that Wolfram is known for, but fine as a “hello world” project. There is even a project that uses an Arduino for more I/O. Between the two videos, you can get a good idea of the sort of things you can accomplish using a Pi with the language.

The real strength in Wolfram is the specialized features it has for things like sound generation and solving differential equations, neither of which will come into play for a simple example. The data drop examples show off these features to visualize PIR data, for example. Also, the language has excellent documentation.

We looked at Wolfram on the Pi a few years ago. These examples, though, go a long way to showing the value gained from interfacing with the Pi’s camera and an Arduino, or from visualizing sensor data in meaningful ways. There’s even IFTTT integration.

Filed under: Raspberry Pi

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A Raspberry Pi Tidy Tide Tracker Predicts Propitious Promenades

The whims of the tides can make walking near the ocean a less than pleasant experience. A beautiful seascape one day may appear as a dismal, mucky, tidal flat the next. Frustrated over these weary walks, [Average Man] created a tidy tide tracker to predict propitious promenade periods.

A Raspberry Pi A+ pulls tide timing information off the web by scraping a web page using Python code. The time for the high tide, when the estuary will be full of water, is shown on a 4-digit 7-seg display. It’s all sandwiched between two smoked black panels to provide a neat case while still letting the LEDs show through.

The code comes from two projects [Average] recalled from a kickstarter timing project and a 7-seg display project. As he points out:

It’s great to learn programming from others, but it’s even better if you learn them well enough to remember, re-use and combine that code later on as well.

The display chips are mounted on a product of his own, the no longer available ProtoPal board. This is a Pi A+ size board with 288 prototyping holes and the standard connector for mounting on the Pi GPIO header. It keeps the project neat and clean.

Filed under: clock hacks, Raspberry Pi

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Home Made Half Life 2 Turret Powered By Pi

To help expand his inter-dimensional empire, [Solderchips] has decided to build his own Half Life 2 turret. This, he hopes, will automatically track and shoot anyone who hinders the work of Our Benefactors. He’s documenting the process, and has just published his first step: creating a 3D model of the turret and printing it out. The final project will use a Raspberry Pi and a webcam to track rebels and fire on them automatically, especially those with crowbars.

He’s made a promising start, using a papercraft model of the turret to build the 3D model, then modifying it to accommodate the brains (the Raspberry Pi) and the brawns, a couple of small servos that will move the top of the turret around. The next step will perhaps be to add a tilt switch so that the whole thing falls asleep if it falls over. The thing to learn from this project, is that at some point you just have to stop thinking about it and actually make something. This paper model is a big step toward success compared to carrying around the dream in your head.

We’ve seen a few Portal Turret builds and a very nice Wheatley build, but not a decent Half Life 2 turret build, so hopefully [Solderchips] will see this through to completion and release all of his files.

Filed under: home entertainment hacks

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Art for Planespotters

We don’t know art, but we know what we like. And this gizmo by [Johan Kanflo] is right up our alley.

First, [Johan] gutted an old Macintosh Classic computer and stuffed a Raspberry Pi inside. Now this is not really a new idea, but [Johan] did a very nice job with the monitor and his attention to detail shows in the rebuilt floppy-drive eject mechanism. He gives it back that characteristic “schlurp” noise.

Then he outfitted the Raspberry Pi with an RTL dongle running dump1090 software to listen to the ADS-B radio signals. The data extracted from the SDR is piped off to an MQTT server with all sorts of data about the airplanes overhead. Another script subscribes to the MQTT topic and figures out which is the closest and runs an image search for the plane type in question, publishing the results back to another MQTT topic. One final script subscribes to this last topic and displays the relevant images on the screen. Pshwew!

The end result is a Macintosh Classic that’s continually updated with whatever planes are closest to being overhead. We’re not at all sure if this is fine art, or part of the useful arts, or maybe even none of the above. But we really like the nice case job and think that using MQTT as a back-end for coordinating multiple concurrent Python scripts (on the same computer) is pretty cool.

Filed under: computer hacks, radio hacks, Raspberry Pi

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Magic Mirror on the Wall, “Is Pi or ESP, Fairest of All?”

“What’s the weather like, honey?” “I don’t know. Let me check the mirror.”  The mirror?

Both [Dylan Pierce] and [Dani Eichorn] have mirror projects that display the weather. They took two different approaches which makes for an interesting comparison. [Dylan] uses a Rapsberry Pi with an actual monitor behind the mirror. [Dani] puts an OLED behind the mirror driven by a ESP8266.  It appears there is more than one way to hack a mirror, or anything, which is what makes hacking fun.

[Dani] started with a picture frame, adding tinting film to the glass so it would reflect. A small section of tint was removed to allow the OLED to be seen. The ESP8266 software connects to the Weather Underground to get the latest information.

The Raspberry Pi version by [Dylan] puts a 27″ monitor behind the mirror. That is either terribly impressive or way over the top but seeing Linux boot behind the mirror makes it worth the effort. The Pi generates a web page which makes this adaptable as a general purpose kiosk.

A video of [Dani’s] mirror in operation, after the break.

 

Filed under: misc hacks, Raspberry Pi, software hacks

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Yet Another Pi Zero USB Hub

The Raspberry Pi Zero was back in stock at Adafruit this week – for about eight minutes. That means a few more people get Pi Zeros, many more will put them up on eBay, and everyone is working on their own version of a Pi Zero USB hub. The latest version of a Pi Zero hub comes from [Nate], and he’s doing this one right. His Pi USB adapter adds four USB ports and features not found in other DIY USB hubs like fuses and ESD protection.

As with other Pi Zero USB hub add-ons, this build relies on a USB hub controller, a few passives, and not much else. The chip used in this hub is the FE1.1s chip, a highly integrated 4-port hub controller that can be found through the usual Chinese resellers. This hub controller doesn’t require much, just a 12MHz crystal, a few passives, and four USB jacks.

Of particular interest is how [Nate] is connecting this hub to the Pi Zero. He’s left the option open for using either a USB cable, or soldering the USB’s differential pairs directly between the Pi and the hub. In either case, the hub should work, and with the addition of the zeners, fuses, and other parts that keep the hub from frying itself, [Nate] might have a very nice project on his hands.

Filed under: Raspberry Pi

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Turning The Pi Zero Into A USB Gadget

The Raspberry Pi Zero is limited, or so everyone says, and everyone is trying to cram a USB hub and WiFi adapter on this tiny, tiny board. One thing a lot of people haven’t realized is that the Raspberry Pi Zero comes with a USB OTG port, meaning it can function as a USB device rather than a USB host. This means the Raspi can become a serial device with just a USB cable, an Ethernet device, MIDI device, camera, or just about anything else you can plug into a USB port. Adafruit has your back with a tutorial for using the USB OTG port as a serial and Ethernet interface, and the possible applications are extremely interesting.

The only requirement for using the USB OTG port for device applications is an update to the kernel. This is easily installed by dumping a few files on an SD card and a employing bit of command line wizardry. The simplest example is setting up the Pi Zero as a USB serial device, allowing anyone to log into a serial console on the Pi with just a USB cable.

A slightly more interesting application is setting up the Pi as an Ethernet gadget. This effectively tunnels all the networking on the Pi Zero through a USB cable and a separate computer. The instructions are extremely OS-specific, but the end result is the same: you can apt-get on a Pi Zero to your heart’s desire with a new kernel loaded onto the SD card and a USB cable.

This experimentation is just scratching the surface of what is possible with the OTG port on the Pi Zero. MIDI devices are easy, and with a ton of GPIOs, the Pi Zero itself could become a very interesting musical instrument. Want the Pi Zero to be a storage device? That’s easy too. The USB Gadget will end up being one of the most exciting uses for the Pi Zero, and we can’t wait to see what everyone will come up with next.

Filed under: Raspberry Pi

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Let Alexa Control Your Life; Guide to Voice-Enable Everything

Let’s face it, automation doesn’t feel quite as futuristic unless you can just say what you want out loud and have the machines flawlessly obey. That is totally possible now — and on the cheap. Well, cheap as far as money goes. It can be an expensive learning curve to get it all working. This will help. [Lindo St. Angel] has put together a guide to navigate voice control of hardware using Amazon’s Alexa SDK.

We previously reported that Amazon’s AI had escaped its hardware prison in the form of the Alexa Skills Kit. Yes, calling it the Alexa SDK above is wrong it’s actually the ASK but nobody knows what that acronym is while most recognize the gist of an SDK. It gives you the hooks and the documentation necessary to leverage the functionality in your own applications. The core functionality of Alexa is voice recognition. Even so, it’s still a tall hill to climb.

[Lindo] has broken down the problem into a very manageable example. The Amazon Voice Service (part of ASK) is used for voice recognition and control. Amazon’s Lambda service connects the ASK to your piece of hardware; in this case he’s using a Raspberry Pi as the server. The final step is to connect your hardware to the Pi. [Lindo] is interfacing a keypad-based home automation system with the Pi but the sky’s the limit at this point.

With all the authentication and connectivity laid bare, this is a lot more approachable. The question is no longer can you connect everything to voice control. The question becomes should you give control of everything over to one single online service?

Filed under: home hacks, internet hacks

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Here Comes Santa Claws

Liberty Games in the UK was looking for a fun way to support charity for the holidays, and we think they succeeded. They decided to set up an arcade crane machine to run over the internet, with each type of toy snagged earning  a donation. Snag a bear, and they will donate £5 to St Mungos, a UK charity that works with homeless or at risk people. Snag one of the rarer Santa toys, and they will donate £20. It’s a great cause, and a nice hack. Behind the scenes, the Internet side of things runs on a Raspberry Pi connected to a PiRack and a couple of PiFace digital interface cards that are wired into the electronics of the crane machine so they could control the buttons on the machine from a Web interface. Unfortunately, it didn’t seem to be running when we tried it, but hopefully someone will give the machine a swift kick shortly to get it going until the Hackaday traffic invariably brings it down again.

One of the interesting thing that they discovered while working on these hacks: they have a pay-out ratio that is determined by the strength of the grabbing arm. The owner can tweak this so that the arm does not grab very firmly, which means a dropped bear. Want to torture your friends with hopes of snagging the best stuffed animals?. Follow the example of this claw machine build all from parts on hand.

Filed under: Holiday Hacks, Raspberry Pi

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POV Globe Display Spins up Full Color Tupac

Persistence of vision projects were once all the rage, judging by a quick review of the literature here on Hackaday. They’ve tapered off a bit lately, but this impressive full-color globe display might just kick-start some new POV projects.

Built as a final project for an EE course, [Evan] and [Kyle]’s project is more about the control electronics and programming than the mechanical end of the build. Still, spinning a 12″ ring of 1/4″ thick acrylic with a strip of APA102 LEDs glued to the edge takes some thoughtful engineering. While the build appears sturdy, [Evan] does admit to a bit of wobble under full steam, which was addressed by adding some weight to the rig. We wonder if mounting half the LEDs on each side of the ring to balance the forces wouldn’t have worked better. True, it would have complicated the coding for the display, but maybe that would have been good for extra points. In any case, the display turned out well and the quality of the images is great. And as an aside: how awesome is it that we live at a time when you can order a six-circuit slip-ring for a project like this for less than $20?

It’s the end of the semester and we love seeing the final projects that have just made it across the finish line. This globe is one, yesterday we saw a voice-controlled digital eye exam, and if you have or know of a final project, don’t forget send us the link!

If POV globes are your thing, be sure to set the Hackaday WABAC machine a few years and check out this Death Star design from 2012 or this globe from 2010.

Filed under: led hacks, misc hacks

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Raspberry Pi Laser Beam Profiler

[Anthony] at UCLA needed to verify the shape of a laser beam. Commercial units for this, as you would expect, are expensive. But a Raspberry Pi with a Pi Noir camera easily handles the task. Not only is the use of the Pi cool but so is the task – they are using lasers to cool molecules to study quantum effects. The Pi camera without the IR filter captures a wide bandwidth making it suitable for use with non-visible lasers. [Anthony] captures the beam along two axes and plots both curves on the LCD touchscreen. That data, based on the pictures, is also available on a host PC. All this in a super compact package with a 7″ touch screen display.

One reason I find this fascinating is I did something similar 1977 at the University of Rochester Laboratory for Laser Energetics. My project was measuring the energy cross-section of a laser beam. The research goal of the Laboratory was the study of inertial confinement laser fusion. While [Anthony] uses an entire camera my project was limited to a 1 dimensional array of charge coupled devices (CCD). The output went to a Tektronix storage terminal and was printed on thermal paper for reference. He uses Python running on the target system. My work used a Z80 development system the size of a tower PC to write my program in assembly language which was then executed on a single board computer. We’ve come a long way. My code is long gone but you can get [Anthony’s] on GitHub.

Filed under: Raspberry Pi, software hacks

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Open Sesame Raspberry Pi Style

[Don] installed an Android tablet into his wife’s vehicle and realized he wanted to allow it to operate and monitor the garage door. His biggest challenge? Meeting the (what he refers to) as the WAF or Wife Acceptance Factor. He decided to use a Web app on a Raspberry Pi, along with a handful of switches and a relay. His list of goals were straightforward:

• Provide the status of the door (open/closed/unknown)
• Open and close the door
• Work across multiple platforms
• Secure enough to connect to the Internet
• Reliable and simple

The Pi uses two switches to determine the position of the door and relay to trigger the existing garage door opener’s operation button. This simple circuit could serve many different purposes, not just opening a garage door. It would be easy to replicate the relay driver, too, if you needed more than one switch for some other purpose.

The Web app is available on GitHub. There’s a cool SVG animation (see left) that shows the status of the door as it opens and closes–presumably to help get the WAF higher. This would be a great starter project for someone getting their feet wet with the Pi or with Web apps. We saw a lot of garage door openers earlier this year, including one for a cat. Still, we liked the simplicity of this one and the mesmerizing animation.

Filed under: Raspberry Pi

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Better Networking With A Macintosh Classic

While it may not be the case anymore, if you compare a Mac and a PC from 1990, the Mac comes out far ahead. PCs suffered with DOS, while the Mac enjoyed real, non-bitmapped fonts. Where a Windows PC required LANMAN to connect to a network, the Mac had networking built right into every single machine. In fact, any Mac from The Old Days can use this built-in networking to connect to the Internet, but most old Mac networking hacks have relied on PPP or other network to serial conversion. [Pierre] thought there was an incomplete understanding in getting old Macs up on the Internet and decided to connect a Mac Classic to the Internet with Apple’s built-in networking.

Since the very first Macintosh, Apple included a simple networking protocol that allowed users to share hard drives, folders, and printers over a local network. This networking setup was called LocalTalk. It wasn’t meant for internets or very large networks; the connection between computers was basically daisy chained serial cables and later RJ-11 (telephone) cables.

LocalTalk stuck around for a long time, and even now if you need to do anything with a Mac made in the last century, it’s your best bet for file transfer. Because of LocalTalk’s longevity, routers and LocalTalk to Ethernet adapters can be found fairly easily. The only problem is finding a modern device that speaks both TCP/IP and LocalTalk. You can’t use a new Mac for this; LocalTalk has been gone from OS X since Snow Leopard. You can do it with a Raspberry Pi, though.

With a little bit of futzing about with MacTCP and a few other pieces of software from 1993 or thereabouts, [Pierre] can even get his old Mac Classic online. Of course the browsers are all horribly outdated (making the Hackaday retro edition very useful), but [Pierre] was able to load up rotten.com. It takes a while with an 8MHz CPU and 4MB of RAM, but it does get the job done.

You can check out [Pierre]’s demo video below.

Filed under: classic hacks, macs hacks

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Maker Barn Organizer Creates Makerspace Access Control System

The MakerBarn is a new makerspace between The Woodlands and Tomball, TX (north of Houston). [George Carlson], one of the founders and a retired design engineer, wanted to make sure only members certified on a machine could use it. He worked with [Kolja Windeler] to create the MACS or Makerspace Access Control System. He has one video explaining MACS and, after the break, another explaining the browser based user interface for the system.

A control box, [George] calls them stations, controls the power to a machine. Member badges have an RFID tag that is read when inserted into the station’s reader. If the member is authorized to use the machine, the power is enabled. For safety, the member’s badge must remain in the reader to maintain power. The reader uses a Photon board from Particle with a WiFi link to a Raspberry Pi server.

[Kolja] developed a Pi system to maintain a database of member numbers and the machines they can use. The list is sent to the stations periodically or when updates occur. The user interface is browser based on the MakerBarn’s LAN so it can be maintained by a computer or smartphone in the space. Presently 21 MACS modules have been built with some going to Hanover University in Germany for their auto hobby shop.

Not only did [George] lead the effort on creating MACS but has been key to getting the construction done inside a pole barn to make the MakerBarn a reality.

Filed under: Hackerspaces, hardware, Raspberry Pi, tool hacks

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Turning a Pi Into a PDP

There’s no better way to learn how to program a computer than assembly, and there’s no better way to do assembly than with a bunch of blinkenlights and switches. Therefore, the best way to learn programming is with a PDP-11. It’s a shame these machines are locked up in museums and the garages of very cool people, but you can build your own PDP-11 with a Raspberry Pi and just a few extra components.

[jonatron] built his own simulated version of the PDP-11 with a lot of LEDs, a ton of switches, and a few 16-bit serial to parallel ICs. Of course the coolest part of any blinkenlight simulator are the front panel graphics, and here [jonatron] didn’t skimp. He put those switches and LEDs on a piece of laser cut acrylic with a handsome PDP11 decal. The software comes with a load of compiler warnings and doesn’t run anything except for very simple machine code programs. That’s really all you can do with a bunch of toggle switches and lights, though.

If this project looks familiar, your memory does not deceive you. The PiDP-8/I was an entry in this year’s Hackaday Prize and ended up being one of the top projects in the Best Product category. We ran into [Oscar], the creator of the PiDP-8, a few times this year. The most recent was at the Hackaday SuperConferece where he gave a talk. He’s currently working on a replica of the king of PDPs, the PDP-11/70.

Video below.

Filed under: classic hacks

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Raspberry Pi Communication Via LASER

[Nick Touran] wanted to make two Raspberry Pi’s communicate wirelessly. There are lots of options, but [Nick] used a LASER and a photoresistor, along with Morse code. If you don’t find Morse code fancy enough, you could always refer to it as OOK (on/off keying). The circuit uses a common LASER module and an ordinary photoresistor that varies in resistance based on light. A resistor forms a voltage divider with the photoresistor and an external A/D reads the resulting voltage.

The circuit works, but we couldn’t help but notice a few items. Not all photoresistors are as sensitive to the same light wavelengths, so for the maximum range you’d want to pick a particular photoresistor.  While the analog to digital converter is certainly workable, we couldn’t help but wonder if you couldn’t set up the divider to use the inherent threshold of the Raspberry Pi’s input pins for a simpler circuit. Of course, if you used the same technique with an Arduino, you could use the built-in A/D converter, and the A/D converter is probably easier to get working.

The prototype only uses one Pi that talks to itself, but if you had two, they could talk to each other using this scheme. The software uses some previous code [Nick] wrote to generate the code and looks to be easy to work with and modify.

Communicating with light isn’t a new idea. Bell had the Photophone, and we’ve covered LASER communications before. And just yesterday we ran a post on LiFi, which attempts to replace WiFi with light.

Filed under: laser hacks, Raspberry Pi

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