Author: Bryan Cockfield

1847 Articles

Carving Terrain Maps Into Plywood With Software Help

November 28, 2022 by 20 Comments

CNC machines are incredibly versatile tools. At a machine shop, they can machine all kinds of metal and plastic parts. Beyond that, they can engrave various materials including glass, and even create PCBs. [Steve] has a CNC machine of his own creation in his shop, and while he might be employing it for those common uses, his artistic creations are on the showcase for today with these 3D topographic relief maps.

The key to creating a good topographic relief map is good material stock. [Steve] is working with plywood because the natural layering in the material mimics topographic lines very well, especially with the high-quality marine-grade birch plywood he is using. Making sure to select pieces without knots improves the final product substantially, as does taking the time to fill any voids. Selecting good stock is only part of the process though. [Steve] is using TouchTerrain, an open source project helmed by [Dr. Chris Harding] of Iowa State University, to create the model which gets fed to the CNC machine. Originally intended for 3D printing applications, the web-based tool lets you easily select an area on the globe and export its topographical data to a standard STL or OBJ file.

With good stock and the ability to easily create 3D topographic maps, anyone with a CNC machine like this could easily reproduce their terrain of choice. We imagine the process might be easily ported to other tools like 3D printers, provided the resolution is high enough. We have also seen similar builds using laser cutters, although the method used is a little different.

Bicycle Gets Turn Signals And Brake Lights For Added Safety

November 28, 2022 by 27 Comments

Traveling by bicycle can be a fun and exciting mode of transportation, and can also save a ton of money compared to driving a car. There are plenty of places around the world where a bicycle is the primary mode of transportation for a significant percentage of the population, but there are many more places that are designed entirely for cars with little thought given to anyone else. For anyone riding a bike, especially for people living in these car-dominated areas, additional safety measures like this LED array are often necessary.

The light array was created by [Estudio Roble] for traveling around his city. The design is based on the Adafruit Circuit Playground Express, which sits directly in the middle of the light fixture. Surrounding it is a diamond-shaped strip of LEDs within an additional ring. The light uses a bright blue color for normal driving, but is programmed to turn red when the accelerometer in the dev board detects braking. There are also integrated turn signals which operate similarly to motorcycle turn signals. The signal is sent wirelessly between the handlebar switch to the lights.

The device itself clips onto any backpack, and since the controller is wireless there are no wires to connect every time a rider gets on their bike. It’s quite an improvement over the complete lack of lighting on most bikes. If you’ve read this far, you need to check out this bicycle headlight which uses a projector to display information directly in the path of travel.

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I’ve Got Two Turntables And A Laser Engraver

November 27, 2022 by 29 Comments

Digital media provides us with a lot of advantages. For something like recording and playing back music, digital copies don’t degrade, they can have arbitrarily high quality, and they can be played in a number of different ways including through digital streaming services. That being said, a number of people don’t feel like the digital experience is as faithful to the original sound as it could be and opt for analog methods instead. Creating analog copies of music is a much tougher matter though, as [Marco] demonstrates by using a laser engraver to produce vinyl records.

[Marco] started this month-long project by assembling and calibrating the laser engraver. It has fine enough resolution to encode analog data onto a piece of vinyl, but he had to create the software. The first step was to generate the audio sample, then process it through a filter to remove some of the unwanted frequencies. From there, the waveform gets made into a spiral, accounting for the changing speed of the needle on the record as it moves to the center. Then the data is finally ready to be sent to the laser engraver.

[Marco] did practice a few times using wood with excellent success before moving on to vinyl, and after some calibration of the laser engraver he has a nearly flawless 45 rpm record ready to hit the turntable. It’s an excellent watch if not for anything than seeing a working wood record. We’ve actually seen a similar project before (without the wood prototyping), and one to play records from an image, but it’s been quite a while.

Thanks to [ZioTibia81] for the tip!

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Racing Cars On A PCB

November 24, 2022 by 14 Comments

Carl Friedrich Gauss was, to put it mildly, a polymath responsible for a large percentage of the things we take for granted in the modern world. As a physicist and mathematician he pioneered several fields of study including within the field of magnetism. But since he died decades before the first car was built, it’s unlikely he could have imagined this creation, a magnetic slot-car race track called the Gauss Speedway by [Jeff McBride], which bears the name of the famous scientist.

The Gauss Speedway takes its inspiration from a recent development in robotics, where many small robots can travel around a large area with the help of circuit traces integrated into their operating area. With the right current applied to these traces, magnetic fields are generated which propel the robots. [Jeff] wanted to build something similar, integrated into a printed circuit board directly, and came up with the slot car idea. The small cars have tiny magnets in them which interact with the traces in the PCB, allowing the cars to move with high precision around the track. He did abandon the traditional slot car controller in favor of a push-button style one directly on the PCB too, which means everything is completely integrated.

While this was more of a demonstration or proof-of-concept, some of the features of this style of robot can be seen in this video, which shows them moving extremely rapidly with high precision, on uneven surfaces, or even up walls. Magnetic robots like these are seeing quite a renaissance, and we’ve even seen some that use magnetism to shape-shift.

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Weasley Clock For Magically Low Cost

November 24, 2022 by 12 Comments

For those unfamiliar with the details of the expansive work of fiction of Harry Potter, it did introduce a few ideas that have really stuck in the collective conscious. Besides containing one of the few instances of time travel done properly and introducing a fairly comprehensive magical physics system, the one thing specifically that seems to have had the most impact around here is the Weasley family clock, which shows the location of several of the characters. We’ve seen these built before in non-magical ways, but this latest build seeks to drop the price tag on one substantially.

To do this, the build relies on several low-cost cloud computing solutions and smartphone apps to solve the location-finding problem. The app is called OwnTracks and is an open-source location tracker which can report data to any of a number of services. [Simon] sends the MQTT data to a cloud-based solution called HiveMQCloud, but you could send it anywhere in principle. With the location tracking handled, he turns to some very low-cost Arduinos to control the stepper motors which point the clock hands to the correct locations on the face.

While the build does rely on a 3D printer for some of the internal workings of the clock, this does bring the cost down substantially when compared to other options. Especially when compared to this Weasley family clock which was built into a much larger piece of timekeeping equipment, having an option for a lower-cost location-tracking clock face like this one is certainly welcome.

Pie Stop For Emergency DNS Needs

November 24, 2022 by 37 Comments

The war on Internet ads rages on, as the arms race between ad blockers and ad creators continues to escalate. To make a modern Internet experience even remotely palatable, plenty of people are turning to DNS-level filters to stop the ads from coming into the network at all. This solution isn’t without its collateral damage though, as the black lists available sometimes filter out something that should have made it to the user. For those emergencies, [Kristopher] created the Pie Stop, a physical button to enact a temporary passthrough on his Pi-Hole.

While [Kristopher] is capable of recognizing a problem and creating the appropriate white list for any of these incidents, others in his household do not find this task as straighforward. When he isn’t around to fix the problems, this emergency stop can be pressed by anyone to temporarily halt the DNS filtering and allow all traffic to pass through the network. It’s based on the ESP-01S, a smaller ESP8266 board with only two GPIO pins. When pressed, it sends a custom command to the Pi-Hole to disable the ad blocking. A battery inside the case allows it to be placed conveniently anywhere near anyone who might need it.

With this button deployed, network snafus can be effectively prevented even with the most aggressive of DNS-level ad blocking. If you haven’t thought about deploying one of these on your own network, they’re hard to live without once you see how powerful they are. Take a look at this one which also catches spam.

Better Air Quality Sensing With CO2

November 21, 2022 by 19 Comments

Measuring air quality, as anyone who has tried to tackle this problem can attest, is not as straightforward as it might seem. Even once the nebulous term “quality” is defined, most sensors use something as a proxy for overall air health. One common method is to use volatile organic compounds (VOCs) as this proxy but as [Larry Bank] found out, using these inside a home with a functional kitchen leads to a lot of inaccurate readings. In the search for a more reliable sensor, he built this project which uses CO2 to help gauge air quality.

Most of the reason that CO2 sensors aren’t used as air quality sensors is cost. They are much more expensive than VOC sensors, but [Larry] recently found one that was more affordable and decided to build this project around it. The prototype used an Arduino communicating over I2C to the sensor and an OLED screen, which he eventually put in a 3D printed case to carry around to sample CO2 concentration in various real-world locations. The final project uses a clever way of interfacing with the e-paper display that we featured earlier.

While CO2 concentration doesn’t tell the full story of air quality in a specific place, it does play a major role. [Larry] found concentrations as high as 3000 ppm in his home, which can cause a drop in cognitive function. He’s made some lifestyle changes as a result which he reports has had a beneficial impact. For human-occupied indoor spaces, CO2 can easily be the main contributor to poor air quality, and we’ve seen at least one other project to address this concern directly.