태그: raspberrypi

Raspberry Pi PoE HAT review

Power over Ethernet (PoE) has been a much requested Raspberry Pi feature from the community. The ability to access power and network along a single cable could prove tremendously useful in a range of deployments. Our Raspberry Pi PoE HAT (£18 / $20) review looks at the official solution from Raspberry Pi. Until now, third-party solutions have been available, most of which add a second Ethernet socket via the HAT and then pass power on to the USB power port. However, the Raspberry Pi 3B+ added four extra GPIO pins specifically to support PoE options and subsequently announced this PoE HAT, a Class 2 device for drawing power directly from a network. This is a more elegant solution that draws its power directly from the Ethernet connection on the Raspberry Pi 3B+ and transfers the power via the four new GPIO pins on the board, while simultaneously enabling a direct network connection. The PoE HAT board uses a custom-built isolation transformer (this is the small white circuit) to turn the 37–57 V DC from Ethernet to a Raspberry Pi-acceptable 5 V. The isolation transformer doesn’t need much space, and the designers have decided to double up with another oft-requested feature: a fan. All of this makes the PoE HAT an appealing addition to the Raspberry Pi, especially for industrial users.Being able to draw power from a network makes the Raspberry Pi easily deployable away from electrical sockets. And the presence of a fan provides a layer of security when using a Raspberry Pi long-term in a hot environment. Because the 3B+ is the only Raspberry Pi to feature these additional PoE pins, you must use this HAT with a Raspberry Pi 3B+ (no other model is currently supported). The Raspberry Pi PoE HAT Setting up the Raspberry Pi PoE HAT Connecting the Raspberry Pi PoE HAT to the Raspberry Pi 3B+ is a simple 30-second job. The HAT connects directly to the 40-pin GPIO header (and four-pin PoE header) on the 3B+ board. Four standoffs and eight screws are used to keep it in place. Then it’s simply a case of connecting a PoE-enabled Ethernet cable to the Raspberry Pi board. It then boots up without the requirement of the USB power cable. A slot for the Pi Camera Module enables you to feed its cable through. It is possible to add a riser to the HAT to extend the GPIO pins out,…
Source: Raspberry Pi PoE HAT review

Programming Minecraft Pi with Wolfram Language

If you are a gamer, you can use the richness of the Wolfram Language to programmatically generate all kinds of interesting structures in the game world of Minecraft, or to add new capabilities to the game. If you are a coder, then you can consider Minecraft just as a fun 3D rendering engine for the output of your code. First, make sure that your Raspberry Pi is up to date and then open Mathematica. Install the MinecraftLink Library by entering the following code, followed by SHIFT+RETURN to evaluate: PacletInstall[“MinecraftLink”] The MinecraftLink library adds a set of new commands to the Wolfram Language for connecting to a running Raspberry Pi Minecraft game. You will find basic documentation on them by searching for ‘Minecraft’ in the Wolfram Help system. Start by launching Minecraft on the Raspberry Pi, and then start a fresh game or open an existing one. In Mathematica, load the library by evaluating: << MinecraftLink Don’t overlook the grave accent (““) at the end.You can find the new commands in Figure 1. If you are connecting from a different computer, you must tell Mathematica the IP address of the Raspberry Pi: MinecraftConnect[“10.10.163.22″] You don’t need to do this if both programs are on the same machine, but if you need to reset the connection, you can use MinecraftConnect or MinecraftConnect[“localhost”]. Let’s test to see if that worked by evaluating: MinecraftChat[“Hello from the Wolfram Language”] You should see the message ‘Hello from the Wolfram Language’ appear briefly in the game. Figure 1 Adding the MinecraftLink library to the Wolfram Language extends it with these new commands Controlling Minecraft using Wolfram Language Minecraft uses a simple {x, y, z} co-ordinate system, where x and z are the horizontal directions and y is the vertical direction. You can see the co‑ordinates in the top-left corner of the screen, but to get them programmatically you can use: MinecraftGetPosition[] We can teleport the character to a new location (in this case, up in the air): MinecraftSetPosition[{0, 50, 0}] If we have just started a game, then 10 blocks in front of us is {0,10,0}. But depending on how mountainous the terrain is, that block might be above or below ground. We can find the surface level with: y = MinecraftGetHeight[{0, 8}] 2 We can test that by looking at the block at that position. It should be Air: pos = {0, y, 8} MinecraftGetBlock[pos] Now…
Source: Programming Minecraft Pi with Wolfram Language

The Squirrel Cafe

Back in 2012, Carsten Dannat was at a science summit in London, during which a lecture inspired him to come up with a way of finding correlations between nature and climate. “Some people say it’s possible to predict changes in weather by looking at the way certain animals behave,” he tells us. “Perhaps you can predict how cold it’ll be next winter by analysing the eating habits of animals? Do animals eat more to get additional fat and excess weight to be prepared for the upcoming winter?” An interesting idea, and one that Germany-based Carsten was determined to investigate further. “On returning home, I got the sudden inspiration to measure the nut consumption of squirrels at our squirrel feeder”, he says. Four years later and his first prototype of the ‘The Squirrel Cafe’ was built, incorporating a first-generation Raspberry Pi. A squirrel enjoying a tasty treat at the Squirrel Cafe A tough nut to crack A switch in the feeder’s lid is triggered every time a squirrel opens it. To give visual feedback on how often the lid has been opened, a seven-segment LED display shows the number of openings per meal break. A USB webcam is also used to capture images of the squirrels, which are tweeted automatically, along with stats on the nuts eaten and time taken. Unsurprisingly perhaps, Carsten says that the squirrels are “focussed on nuts and are not showing interest at all in the electronics!” So, how do you know how many nuts have actually been eaten by the squirrels? Carsten explains that “the number of nuts eaten per visit is calculated by counting lid openings. This part of the source code had been reworked a couple of times to get adjusted to the squirrel’s behaviour while grabbing a nut out of the feeder. Not always has a nut been taken out of the feeder, even if the lid has been opened.” Carsten makes an assumption that if the lid hasn’t been opened for at least 90 seconds, the squirrel went away. “I’m planning to improve the current design by implementing a scale to weigh the nuts themselves to get a more accurate measurement of nut consumption,” he says. Follow along with the cafe’s tweets @TheSquirrelCafe Just nuts about the weather! The big question of course is what does this all tell us about the weather? Well, this is a complicated area too, as Carsten…
Source: The Squirrel Cafe

Beocreate 4-Channel Amplifier review

The Beocreate 4-Channel Amplifier enables you to upgrade classic speakers with a Raspberry Pi. Our Beocreate 4-Channel Amplifier review tests out this speaker upgrade kit. Somewhere, in the darkest recesses of your garage or loft, there may be speakers. Not speakers like today’s tiny, tinny Bluetooth excuses, but proper speakers: large, heavy, loud. Although these monoliths are still capable of outperforming today’s examples, they are becoming increasingly useless. Why? Well, unless you’re holding on to your vintage amplifiers, there’s nothing left to drive them. So your wonderful, expensive pieces of engineering excellence sit gathering dust, playing only John Cage’s 4′33″. Until now. This review first appeared in The MagPi 72 and was written by PJ Evans. Click here to download a free digital edition of The MagPi magazine. Beocreate 4-Channel Amplifier review Audiophile giant Bang & Olufsen has partnered with HiFiBerry to produce the Beocreate, a high-end digital sound processor and amplifier for the Raspberry Pi. Not so much a HAT as a full fedora, scarf, and cape, this monster upgrades your favourite tiny computer to audiophile quality. Four channels (a whopping 2×60 W and 2×30 W) can be configured to drive not only standalone speakers, but also their individual woofers and tweeters. The on-board DSP can be endlessly configured over the web, even in real-time as you’re listening, allowing for an incredible amount of tinkering that will have even the most dedicated perfectionist thinking ‘Oh, that’ll do’. The Beocreate also upcycles your classic speakers to work with 21st century music sources. Add a Pi, hook up the wires, install some software, and you’ve got a Bluetooth, Spotify, and AirPlay speaker like no other. Putting a new lease of life into vintage B&O speakers Band and Olufsen with Raspberry Pi B&O has targeted its classic CX50 and CX100 speakers, providing built-in profiles for the DSP to get the absolute best from them and guides to install everything inside the speakers. The good news is it also works with any passive speaker, providing a default ‘safe’ profile that you can then tweak if you see fit. For a rather breathtaking £149, you do get very good build quality. On board are a power input (which also powers your Pi), four speaker terminals, and TOSLink connectors for digital input and output, enabling multiple Beocreates to be chained together. Your Raspberry Pi plugs in upside-down, with thoughtfully provided posts to hold it firmly in place.…
Source: Beocreate 4-Channel Amplifier review

Nemo-Pi

Nemo-Pi is an underground weather station powered by Raspberry Pi. Discover how Raspberry Pi computers are being used to protect coral reefs from climate change. For the past two years, the Save Nemo Foundation has worked hard to protect coral reefs off the coast of Thailand and Indonesia. Its members have been sinking concrete blocks next to the reefs, allowing diving and snorkelling boats to safely moor by using them as anchor points. In doing so, they’ve eased the problem of boat crews dropping anchor directly into the reefs, which has already caused significant damage. But while that has had a positive effect on the creeping destruction, the organisation spotted another opportunity. “We realised we could do more by making these moorings smart,” says its CEO Diemo Niemann. “So we created a plan to collect underwater physical and chemical data that is not only essential for science, but helpful for local people and their business.” The result? Nemo-Pi, a device able to measure temperature, visibility, pH levels, and the concentration of CO2 and nitrogen oxide at each anchor point. The Nemo-Pi project, which won a Google Impact Challenge 2018 award,needs volunteer programmers. Interested? Email [email protected] Nemo-Pi: Underwater weather station Every one of the concrete moorings has a buoy attached on top and, as it bobs in the water, it shows boat crews where they can anchor. The idea behind Nemo-Pi is to put an encased Raspberry Pi into the buoy, attach it to a solar panel for power, include a GPS device so that its location can be determined, and run an array of sensors from the computer into the sea that can then feed back vital information. A team of programmers has been busy coding in Python and C++ on a slimmed Debian environment to create the Nemo‑Pi itself. Meanwhile, much testing has been carried out to ensure the project is saltwater resistant and able to withstand high levels of UV irradiation. It is important that the entire setup is simple, sustainable, affordable and reliable, not to mention energy-efficient. Monitoring climate change with Raspberry Pi “The Nemo-Pi has a modified real-time clock and GPRS/GPS hub,” Diemo explains. “With this, the device is powered up and down to save energy and send its data direct to our server, which takes care of the visualisation and processing. During the night, Nemo-Pi is automatically powered off and we have developed a library to…
Source: Nemo-Pi

Robot Glockenspiel

This robot Glockenspiel uses Raspberry Pi to bash out its own tunes. Robots have already blown their own trumpet: Toyota developed a humanoid in 2004 which could play When You Wish Upon a Star by clasping the instrument in its hands and blowing air through its mouth. Since then, we’ve seen robots play the drums and guitar; even going as far as recording an album. But now we’ve heard the results of a Raspberry Pi playing a glockenspiel and it’s been music to our ears. It’s all thanks to Robin Newman whose love of computers and music goes way back. In the 1980s, Robin networked 24 BBC Micros and had them play parts of a Bach Brandenburg Concerto. “Today, 80 percent of my work with Raspberry Pi boards involves Sonic Pi,” he says. Robot Glockenspiel controlled by Raspberry Pi Robin got the idea for a Sonic Pi-controlled glockenspiel after seeing similar projects online that used an Arduino. “Version 3.1 was a game changer because it allowed Sonic Pi to communicate with the outside world using either MIDI signals or Open Sound Control messages,” he explains. “It enables Sonic Pi to interact with Python-controlled devices and to interact easily with signals to and from the Pi’s GPIO pins. I wanted to use the fact that it could control a glockenspiel and play itself at the same time to accompany the instrument.” Setting up Robin already had a glockenspiel. A 30-year-old gift to his son, it was languishing in his attic. As such, he sought to produce an easily constructed project that could be added to the instrument. The Pi, he envisaged, would control hammers to strike the glockenspiel’s metal bars and he decided to use solenoids as the actuators. “I bought a 5 V, Adafruit-sourced solenoid and I already had a suitable power supply to hand,” he recalls. “I also had a power transistor and projection diode from an Arduino starter kit. I was able to connect them up to a GPIO pin and use the GPIO Zero LED command to switch it on and off. Hitting the keys This worked fine and so the question was how could this small movement be used to hit the keys.” It was then that he turned to LEGO. Hammer time Before the Pi was launched, Robin had spent a few years working with the LEGO EV3 system, mainly producing colour-sorting robots. “After some experimentation, it turned…
Source: Robot Glockenspiel

Ghost Detector built with Raspberry Pi

The truth is out there… At least that’s what they used to say on The X-Files. Well, if there is any paranormal activity around, Anthony DiPilato’s sensor-packed Ghost Detector aims to find it. While he built the device around two years ago, this top-secret project has only just been shared with the wider world. The idea stemmed from a desire to create a home-made present for his father. “My dad watches a lot of paranormal investigation shows,” says Anthony, “so I thought it would be a fun project to give as a Christmas gift.”

Ghost Detector and infrared camera While the project started off as a simple Arduino-based EMF (electromagnetic field) meter, it quickly evolved into something far more ambitious. “I saw Raspberry Pi offers an infrared camera,” recalls Anthony, “so I decided to build something that could record video with overlaid sensor data.” The Raspberry Pi records video, audio, and sensor data, then saves it to a USB flash drive. Mounted on top of the device, an official Raspberry Pi 7-inch touchscreen provides a user interface, while also displaying the data from the numerous sensors and a live video view from the infrared camera. Featuring a pistol-grip handle, the body of the detector was 3D-printed on Anthony’s newly acquired Monoprice Maker Select. He designed the enclosure using the Autodesk Fusion 360 CAD software, which offers a free licence for hobbyists. “Since it is a pseudoscientific instrument, I wanted to make it look as ridiculous as possible,” he tells us. “So I included rabbit-ear telescopic antennas [for the EMF sensors] and a Geiger tube. I thought the stained wood enclosure would match that aesthetic.” Anthony tested the electronics out before cramming them into the 3D-printed enclosure Sensory overload Continuing the theme of making it as ludicrous as possible, Anthony crammed the detector with “as many sensors as I could fit.” Along with the EMF sensors, there’s a magnetometer (compass), altimeter, temperature and barometric pressure sensor, microphone, and a Geiger counter to measure radioactivity. Most of the sensors and other electronics are mounted on stripboard, including two 5 V 3 A step-up power supplies, an Arduino Nano, and a logic level converter to interface the Nano to the Raspberry Pi. The Geiger counter is a separate board, while its Geiger tube is mounted on the front along with the camera and two lots of infrared LEDs either side. To power the…
Source: Ghost Detector built with Raspberry Pi

AI made easy in The MagPi #72

We’ve covered various AI projects here on The MagPi, most notable when we released issue 57 with the AIY Voice Projects Kit on the cover, however we’ve never gone deep into what AI on Pi actually means. In this issue we get into the nitty gritty, and give you the skills to make a magic seeing wand, an awesome automated robot, and an offline speech recognition system. Make music with Raspberry Pi We’re also excited to show off our complete guide to creating your own recording studio with a Raspberry Pi so that you can compose the music you’ve always wanted to make. All you need to do is supply your own MIDI keyboard and musical talent. Make music with the Raspberry Pi in issue 72 of The MagPi Also in this issue Build your own mini magic mirror. A bedside table-sized magic mirror project. Learn Pygame Zero – part 2. Continue learning about making games with Pygame Zero. Knit your own sensor in the Pi Bakery. This sensor will stretch the limits of your imagination. Hack Minecraft Pi with Mathematica. Change your Minecraft world entirely with code. Get to know the file manager on Raspbian. The humble file manager can do a lot. And much, much more. Grab your copy right now! The post AI made easy in The MagPi #72 appeared first on The MagPi Magazine.
Source: AI made easy in The MagPi #72