Raspberry Pi

1836 Articles

IOT Pinball Puts Oktoberfest Fun On Tap

August 3, 2020 by 5 Comments

We don’t really miss going out to bars all that much, unless you’re talking about the one downtown with all the pinball machines. Don’t get us wrong — pinball emulators have gotten crazy good, and you can find exact digital replicas of most machines to play on your phone or whatever. But it just doesn’t compare to the thrill of playing a real cabinet.

Don’t despair, because for the next couple of weeks, you can queue up to play on a real Oktoberfest pinball machine that’s sitting in Espoo, Finland. The controls are hooked up to a Raspberry Pi 4 through a custom HAT, along with a camera pointed at the playfield and another focused on the backglass screen. The game development/video streaming company Surrogate is hosting a tournament over the internet, and will be giving prizes to the top ten high rollers.

We usually have to wait until the holiday season to come across these remote-reality gaming opportunities. Having played it several times now, we recommend spamming the flippers until you get a feel for the lag. Also, just holding the flippers up while the ball is in the upper half of the playfield will catch a lot of balls that you might otherwise lose due to flipper lag, and sometimes they end up back in front of the launcher to shoot again. After the break, check out a brief but amusing video of setting up the cameras and Pi that includes a taste of the Oktoberfest music.

The tournament runs until the end of August, which should be enough time for somebody to set up CV and a keyboard to play this automatically. Need inspiration? Here’s an open-source pinball machine that can play itself.

Continue reading “IOT Pinball Puts Oktoberfest Fun On Tap” →

The Internet Of Bubble Machines

July 31, 2020 by 15 Comments

Everyone loves a good bubble machine. These oddly satisfying novelty items have brought children and adults mindless entertainment since their inception. [8BitsAndAByte] had the same thought, but wanted to give their bubble machine a taste of the IoT-age.

First, they modified an off-the-shelf bubble machine with a Raspberry Pi and relay module. The Pi can easily trigger the bubbling mechanism by controlling power to the machine using the relay. Seems simple enough. The part of this project that might be a bit more unfamiliar to you is controlling the robot over the internet using remo.tv.

Remo.tv is a robot controller platform that’s both free and open-source, and we’ve seen [8BitsAndAByte] take advantage of this web controller before. Seems like they’re really getting the hang of it. Their writeup links to a detailed setup guide for configuring the Pi, so hopefully, that’s not too much trouble.

Couple the IoT setup with a Pi camera and you’ve got a live stream that’s admittedly oddly satisfying to watch with or without the bubbles.

Continue reading “The Internet Of Bubble Machines” →

Do You Know Where Your Children Are? Check The Weasley Clock

July 29, 2020 by 16 Comments

What’s the coolest thing you could build for a Harry Potter fan, aside from a working magic wand or Quidditch broomstick? We would have to say a Weasley clock that shows the whereabouts of everyone in the family is pretty high on the list, especially if that fan is a wife and mother.

Here’s how it works: they’ve set up geofences to define the boundaries of home, each person’s school or workplace, and so on. The family’s locations are tracked through their phones’ GPS using Home Assistant, which is hosted on a Raspberry Pi. Whenever someone’s location changes, the Pi alerts the clock over MQTT, and it moves the 3D-printed hands with servos.

The clock has some interesting granularity to it as well. As someone gets closer to home, their pointer’s distance reflects that in its proximity to the Home slice. And Home itself is divided into the main house and the shop and reflected by the pointer’s position.

We particularly like the attention to detail here, like the art poster used for the clock’s face that includes all the Weasley’s whereabouts in the background. It’s built into a thrift store grandmother clock, which is smaller than a grandfather clock but no less majestic. In the future there are plans to implement the clock’s chimes to announce that someone is back home.

No matter what you’re into, the whereabouts clock idea can probably fit that universe. For instance, here’s one that uses LEGO mini-fig heads to locate roommates.

RadioGlobe Takes The World Of Internet Radio For A Spin

July 27, 2020 by 26 Comments

There’s no denying that the reach and variety of internet radio is super cool. The problem is that none of the available interfaces really give the enormity of the thing the justice it deserves. We long for a more physical and satisfying interface for tuning in stations from around the globe, and [Jude] has made just the thing.

RadioGlobe lets the user tune in over 2000 stations from around the world by spinning a real globe. It works by using two absolute rotary encoders that each have a whopping 1024 positions available. One encoder is stuck into the South Pole, and it reads the lines of longitude as the user spins the globe.

The other encoder is on the left side of the globe, and reads whatever latitude is focused in the reticle. Both encoder are connected to a Raspberry Pi 4, though if you want to replicate this open-source project using the incredibly detailed instructions, he says a Raspberry Pi 3 B+ will work, too.

In the base there’s an LCD that shows the coordinates, the city, and the station ID. Other stations in the area are tune-able with the jog wheel on the base. There’s also an RGB LED that blinks red while the station is being tuned in, and turns green when it’s done. We totally dig the clean and minimalist look of this build — especially the surprise transparent bottom panel that lets you see all the guts.

There are three videos after the  break – a short demo that gives you the gist of how it works, a longer demonstration, and a nice explanation of absolute rotary encoders. Those are just the tip of the iceberg, because [Jude] kept a daily vlog of the build.

Maybe you just long for a web radio that dials in vintage appeal. This antique internet radio has a lot of features, but you wouldn’t know it from the outside.

Continue reading “RadioGlobe Takes The World Of Internet Radio For A Spin” →

A Complete Raspberry Pi Power Monitoring System

July 24, 2020 by 59 Comments

As the world has become more environmentally conscious, we’ve seen an uptick in projects that monitor or control home energy use. At a minimum one of these setups involves a microcontroller and some kind of clamp-on current sensor, but if you’re looking for resources to take things a bit farther, this Raspberry Pi energy monitoring system created by [David00] would be a great place to start.

This project includes provides software and hardware to be used in conjunction with the Raspberry Pi to keep tabs on not just home energy consumption, but also production if your home has a solar array or other method of generating its own power. Data is pulled every 0.5 seconds from a MCP3008 ADC connected to up to five six current sensors to provide real-time utilization statistics, and visualized with Grafana so you can see all of the information at a glance.

While [David00] has already done the community a great service by releasing the hardware and software under an open source license, he’s also produced some absolutely phenomenal documentation for the project that’s really a valuable resource for anyone who wants to roll their own monitoring system. He’s even offering hardware kits for anyone who’s more interested in experimenting with the software side of things than building the PCB.

Home energy monitoring projects are certainly nothing new, but the incredible advances we’ve seen in the type of hardware and software available for DIY projects over the last decade has really pushed the state-of-the-art forward. With so many fantastic resources available now, the only thing standing between you and your own home energy monitoring dashboard is desire and a long weekend.

TinyPilot Provides KVM-over-IP, With Low Cost And Even Lower Latency

July 24, 2020 by 45 Comments

Remote access is great, but if the machine stops booting, ceases to connect to the network, or needs low-level interaction like BIOS settings or boot management, remote access is worthless because it’s only available once the host computer is up and running. The usual solution is to drag a keyboard and monitor to the machine in question for physical access.

Ubuntu laptop (right) being accessed over IP, via web browser on the left.

For most people, swapping cables in this way is an infrequent task at best. But for those who work more closely with managing hardware or developing software, the need to plug and unplug a keyboard and monitor into machines that otherwise run headless can get tiresome. The modern solution is KVM (keyboard, video, mouse) over IP, but commercial options are expensive. [Michael Lynch]’s TinyPilot on the other hand clocks in at roughly $100 of parts, including a Raspberry Pi and USB HDMI capture device. It does have to drop the ‘M’ from KVM (meaning it does not support a mouse yet) but the rest of it hits all the bases, and does it all from a web browser.

What exactly does TinyPilot do? It provides remote access via web browser, but the device is an independent piece of hardware that — from the host computer’s point of view — is no different from a physical keyboard and monitor. That means keyboard and video access works before the host machine even boots, so even changing something like BIOS settings is no problem.

[Michael] demonstrates his design in the video embedded below, but we encourage you to check out the project page for a fascinating exploration of all the challenges that were part of TinyPilot’s development.

Continue reading “TinyPilot Provides KVM-over-IP, With Low Cost And Even Lower Latency” →

Let’s Take A Closer Look At This Robotic Airship

July 22, 2020 by 30 Comments

It’s not a balloon, however shiny its exterior may seem. This miniature indoor robotic airship created by the University of Auckland mechanical engineering research group [New Dexterity] is an asymmetric system experimenting with the possibilities of an open-source helium-based airship.

Why a helium airship, as opposed to a fixed wing aircraft? The group wanted to experiment with the advantages of lighter-than-air (LTA) travel, namely the higher mobility and looser path planning constraints. Furthermore, LTA airships have a less obstructed field of vision and fewer locomotion issues. While unmanned aerial vehicles (UAV) may be capable of hovering in one place, their lift is generated by rotor thrust, which drains their batteries quickly in the order of minutes. LTA airships can hover for longer periods of time.

The design was created for educational and research purposes, focusing on the financial feasibility of manufacturing the platform, the environmental impact of the materials, and the helium loss through the balloon-like envelope. By measuring these parameters, the researchers are able to study the effects of circumstances such as the cost of indoor commercial balloons and the mechanical properties of balloon materials.

The airship gondola was designed and 3D printed in a modular fashion, then attached to the envelope with Velcro. The placement with respect to the horizontal symmetry of the gondola was done for flight stability, with several configurations tested for the side rotor angle.

The group open-sourced their CAD files and ROS interface for controlling the airship. They primarily use off-the-shelf components such as Raspberry Pi boards, propellers, a DC single brushed motor driver carrier, and LiPo batteries for a total cost of $90 for the platform, with an addition $20 for the balloon and initial helium filling. The price is comparable to the cost of indoor blimps like the Blimpduino 2.0.

You can check out the completed airship below, where the team demonstrates its path following capabilities based on a carrot chasing path finding algorithm. And if you’re interested in learning more about the gotchas of building lighter-than-air vehicles, check out [Sophi Kravitz’s] blimp talk from Hackaday Belgrade.

Continue reading “Let’s Take A Closer Look At This Robotic Airship” →