Author: Bryan Cockfield

1755 Articles

3D Printer Streaming Solution Unlocks Webcam Features

April 20, 2024 by 7 Comments

While 3D printer hardware has come along way in the past decade and a half, the real development has been in the software. Open source slicers are constantly improving, and OctoPrint can turn even the most basic of printers into a network-connected powerhouse. But despite all these improvements, there’s still certain combinations of hardware that require a bit of manual work.

[Reticulated] wanted an easy way to monitor his prints over streaming video, but didn’t have any of the cameras that are supported by OctoPrint. Of course he could just point a cheap network-connected camera at the printer and be done with it, but he was looking for a bit better integration than that. In the process, he demonstrates how to unlock some features hidden in inexpensive webcams.

He set about building something that wouldn’t require buying more equipment or overloading the limited hardware responsible for the actual printing. A few of his existing cameras have RTMP support, which allows a fairly straightforward setup with YouTube Live once Monaserver is set up to handle the RTMP feeds from the cameras and OBS Studio is configured to stream it out to YouTube. Using the OctoPrint API, he was able to pull data such as the current extruder temperature and overlay it on the video.

One of the other interesting parts of this build is that not all of [Reticulated]’s cameras have built-in RTMP support but following this guide he was able to get more of them working with this setup than otherwise would have had this capability by default. Even beyond 3D printing, this is an excellent guide (and tip) for getting a quick live stream going for whatever reason. For anything more mobile than a working 3D printer, though, you might want to look at taking your streaming setup mobile instead.

This Go-Kart Rides On A Pallet

April 17, 2024 by 16 Comments

Many beginner woodworkers, looking to offset the introductory costs of starting a hobby, will source their wood from pallets. Generally they’re easily found and can be low or no cost, but typically require a bit of work before they’re usable in a project. [Garage Avenger] is looking to do something a little outside of the box with his pallet project, though. He’s using raw pallets as a chassis for a four-speed go-kart, partially for the challenge and excitement and also to one-up a Pinterest post.

Almost immediately, though, the other major downside of working with pallets arose which is that they’re generally built out of low-grade pine which is soft and flexible. Flexibility is generally not a good thing to have in a vehicle frame so plenty of the important parts of this build were strengthened with steel tubing including the rear axle, steering mounts, and a few longitudinal supports to strengthen the overall frame. After working out some kinks with ordering a few of the wrong parts, and mounting the steering box backwards, it was time to test out the four-speed engine (and brakes) on the the go-kart, making it nearly ready for the road.

To complete the build, some tidying of wiring and fuel lines was done, along with improving some of the non-critical parts of the build like the bucket seat. Of course, adding pallet spoilers and body kit puts the finishing touches on the build and the go-kart is finally ready to tear up the local go-kart track and the less-inspiring Pinterest projects. [Garage Avenger] is no stranger to strange vehicle builds, either. Although it’s a bit out of season for most of our northern hemisphere readers now, his jet-powered street sled is still worth a view.

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Garage Door Automation With No Extra Hardware

April 11, 2024 by 10 Comments

Home automation projects have been popular as long as microcontrollers have been available to the general public. Building computers to handle minutiae so we don’t have to is one of life’s great joys. Among the more popular is adding some sort of system to a garage door. Besides adding Internet-connected remote control to the action of opening and closing, it’s also helpful to have an indicator of the garage door state for peace-of-mind. Most add some sensors and other hardware to accomplish this task but this project doesn’t use any extra sensors or wiring at all.

In fact, the only thing added to the garage door for this build besides some wiring is the microcontroller itself. After getting the cover of the opener off, which took some effort, a Shelly Uni was added and powered by the 12V supply from the opener itself. The garage door opener, perhaps unsurprisingly, has its own way of detecting when the door is fully open or closed, so some additional wire was added to these sensors to let the microcontroller know the current state. Shelly Uni platforms have a WiFi module included as well, so nothing else was needed for this to function as a complete garage door automation platform.

[Stephen] uses Home Assistant as the basis for his home automation, and he includes all of the code for getting this platform up and running there. It wouldn’t be too hard to get it running on other openers or even on other microcontroller platforms; the real key to this build is to recognize that sometimes it’s not necessary to reinvent the wheel with extra sensors, limit switches, or even power supplies when it’s possible to find those already in the hardware you’re modifying. This isn’t always possible, though, especially with more modern devices that might already be Internet-connected but probably don’t have great security.

Baseboard Heaters Get Automated

April 10, 2024 by 12 Comments

If you’re lucky enough to have central heating and/or air conditioning, with an automatic thermostat, you probably don’t have to worry too much about the outside temperature. But central HVAC is far from the only way of maintaining temperature in a home. From wood stoves to boilers there are many options depending on your climate and home type, and [Murphy’s Law] has a decentralized baseboard system instead of something centralized. An ESP8266 solution was found that was able to tie them all together.

There are other types of baseboard heaters, but in [Murphy’s Law]’s case the heaters were electric with a separate thermostat for each heater. Rather than build a control system from the ground up to replace the thermostats, turnkey smart wall switches were used instead. These switches happened to be based on the popular ESP8266 microcontroller, like plenty of other off-the-shelf automation solutions, which meant less work needed to be done on the line voltage side and the microcontroller’s firmware could be easily customized for use with Home Assistant.

While [Murphy’s Law] doesn’t live in the home with the fleet of electric baseboard heaters anymore, the new home has a single baseboard heater to keep a bathroom warm since the central heating system doesn’t quite keep it warm enough. This system is able to scale up or down based on number of heaters, though, so it’s still a capable solution for the single room and has since been updated to use the ESP32. All of the code for this project is available on GitHub as well, and for those of you attempting to add other HVAC components to a home automation system this project that loops in a heat pump is worth taking a look at as well.

2024 Home Sweet Home Automation Contest

Wozamp Turns Apple II Into Music Player

April 10, 2024 by 9 Comments

Besides obvious technological advancements, early computers built by Apple differed in a major way from their modern analogs. Rather than relying on planned obsolescence as a business model, computers like the Apple II were designed to be upgradable and long-term devices users would own for a substantially longer time than an iPhone or Macbook. With the right hardware they can even be used in the modern era as this project demonstrates by turning one into a music player.

The requirements for this build are fairly short; an Apple II with a serial card and a piece of software called surl-server which is a proxy that allows older computers to communicate over modern networks. In this case it handles transcoding and resampling with the help of a Raspberry Pi 3. With that all set up, the media player can play audio files in an FTP network share or an online web radio station. It can also display album art on the Apple II monitor and includes a VU meter that is active during playback.

Although the 11.52 kHz sampling rate and 5-bit DAC may not meet the stringent requirements of audiophile critics, it’s an impressive build for a machine of this era. In fact, the Apple II has a vibrant community still active in the retrocomputing world, with plenty of projects built for it including others related to its unique audio capabilities. And if you don’t have an original Apple II you can always get by with an FPGA instead.

Emails Over Radio

April 9, 2024 by 38 Comments

The modern cellular network is a marvel of technological advancement that we often take for granted now. With 5G service it’s easy to do plenty of things on-the-go that would have been difficult or impossible even with a broadband connection to a home computer two decades ago. But it’s still reliant on being close to cell towers, which isn’t true for all locations. If you’re traveling off-grid and want to communicate with others, this guide to using Winlink can help you send emails using a ham radio.

While there are a number of ways to access the Winlink email service, this guide looks at a compact, low-power setup using a simple VHF/UHF handheld FM radio with a small sound card called a Digirig. The Digirig acts as a modem for the radio, allowing it to listen to digital signals and pass them to the computer to decode. It can also activate the transmitter on the radio and send the data from the computer out over the airwaves. When an email is posted to the Winlink outbox, the software will automatically send it out to any stations in the area set up as a gateway to the email service.

Like the cellular network, the does rely on having an infrastructure of receiving stations that can send the emails out to the Winlink service on the Internet; since VHF and UHF are much more limited in range than HF this specific setup could be a bit limiting unless there are other ham radio operators within a few miles. This guide also uses VARA, a proprietary protocol, whereas the HF bands have an open source protocol called ARDOP that can be used instead. This isn’t the only thing these Digirig modules can be used for in VHF/UHF, though. They can also be used for other digital modes like JS8Call, FT8, and APRS.

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A Long-Range Meshtastic Relay

April 3, 2024 by 23 Comments

In the past few years we’ve seen the rise of low-power mesh networking devices for everything from IoT devices, weather stations, and even off-grid communications networks. These radio modules are largely exempt from licensing requirements due to their low power and typically only operate within a very small area. But by borrowing some ideas from the licensed side of amateur radio, [Peter Fairlie] built this Meshtastic repeater which can greatly extend the range of his low-power system.

[Peter] is calling this a “long lines relay” after old AT&T microwave technology, but it is essentially two Heltec modules set up to operate as Meshtastic nodes, where one can operate as a receiver while the other re-transmits the received signal. Each is connected to a log-periodic antenna to greatly increase the range of the repeater along the direction of the antenna. These antennas are highly directional, but they allow [Peter] to connect to Meshtastic networks in the semi-distant city of Toronto which he otherwise wouldn’t be able to hear.

With the two modules connected to the antennas and enclosed in a weatherproof box, the system was mounted on a radio tower allowing a greatly increased range for these low-power devices. If you’re familiar with LoRa but not Meshtastic, it’s become somewhat popular lately for being a straightforward tool for setting up low-power networks for various tasks. [Jonathan Bennett] explored it in much more detail as an emergency communications mode after a tornado hit his home town.

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