Better Macro Images With Arduino Focus Stacking

January 26, 2023 by 17 Comments

If you’ve ever played around with macro photography, you’ve likely noticed that the higher the lens magnification, the less the depth of field. One way around this issue is to take several slices at different focus points, and then stitch the photos together digitally. As [Curious Scientist] demonstrates, this is a relatively simple motion control project and well within the reach of a garden-variety Arduino.

You can move the camera or move the subject. Either way, you really only need one axis of motion, which makes it quite simple. This build relies on a solid-looking lead screw to move a carriage up or down. An Arduino Nano acts as the brains, a stepper motor drives the lead screw, and a small display shows stats such as current progress and total distance to move.

The stepper motor uses a conventional stepper driver “stick” as you find in many 3D printers. In fact, we wondered if you couldn’t just grab a 3D printer board and modify it for this service without spinning a custom PCB. Fittingly, the example subject is another Arduino Nano. Skip ahead to 32:22 in the video below to see the final result.

We’ve seen similar projects, of course. You can build for tiny subjects. You can also adapt an existing motion control device like a CNC machine.

Continue reading “Better Macro Images With Arduino Focus Stacking” →

Adding Electronic Shifter Functionality To Bicycle Derailleur

January 26, 2023 by 19 Comments

For the overwhelming majority of bicycles out there that feature multiple gears, switching between these is done purely mechanically, with a cable. Generally this uses a derailleur, which forms part of the gear switching and chain tensioning mechanism. As a mechanical system, it’s reliable when well maintained, but tuning it can be a real hassle. This is where an electronic shifter should be able to provide faster, more reliable and quieter shifting, and is also where [Jesse DeWald]’s electronic shifting project begins.

As [Jesse] points out in the introductory article on electronic shifting, it’s not a new concept, with everyone from Shimano (Di2) to Archer and others coming up with their own version. Some of these require replacing the existing derailleur, while others should allow for non-destructive modification. What [Jesse] did not find among this constellation of options was a version that’d work with existing derailleurs, did not require destructive modifications and have a long battery life.

[Jesse]’s design omits the servo present in Archer’s design, and uses the existing derailleur spring, with the reasoning explained in a nice spring physics refresher. Instead a stepper is used along with a matched balancer spring that in testing managed over 3 months of standby time with a 3,700 mAh Li-ion battery and thousands of shifts. At the core of the system is an Arduino Pro Mini board, the code for which is available along with the design plans.

The project is not done at this point, of course, with a whole range of improvements still to be added, including a case, so that the shifter can be used outside in the rain.

A Simple Air Suspension Demo With Lego Technic

January 25, 2023 by 19 Comments

The most common suspension systems on automobiles rely on simple metal springs. Leaf spring and coil spring designs both have their pros and cons, but fundamentally it’s all about flexing metal doing the work. Air suspension works altogether differently, employing gas as a spring, as demonstrated by this simple Lego build from [JBRIX]. 

The suspension system is employed on a Lego Technic car, with a relatively unsophisticated design. The car has no real form of propusion, and serves solely to demonstrate the air suspension design. They may look like dampers, but the system is actually using Lego pneumatic pistons as springs for each wheel. The pistons are connected to the upper control arm of a double wishbone suspension setup. Each piston is pneumatically connected to a main reservoir. With the reservoir, and thus the pistons, pressurized, the suspension system can support the weight of the car. If a bump perturbs a wheel, the piston compresses the air in the system, which then returns the piston to its original position, thus serving as a spring. If the reservoir is vented, the suspension collapses. Air springs on real, full-sized automobiles work in basically the same way. However, they usually have a separate reservoir per corner, keeping each wheel’s suspension independent.

Overall, if you’re working on some kind of Lego rambler, you might find this suspension concept useful. Alternatively, you might simply find it good as a learning aid. If you want to learn more about oddball suspension systems, we can help there too. Video after the break.

Continue reading “A Simple Air Suspension Demo With Lego Technic” →

Toxic Telescope Makes You Mad As A Hatter

January 25, 2023 by 51 Comments

[Hank Green] posted an interesting video about the first liquid mirror telescope from back in the 1850s. At the time, scientists were not impressed. But, these days, people are revisiting the idea. The big problem with the early telescope is that it used mercury. Mercury is really bad for people and the environment.

The good thing about a liquid scope is that you can pretty easily make a large mirror. You just need a shallow pool of liquid and a way to spin it. However, there are downsides. You need to isolate the liquid from vibrations and dust. Another downside is that since gravity makes the shape of the mirror, these telescopes only go one way — straight up.

Continue reading “Toxic Telescope Makes You Mad As A Hatter” →

A red and blue Lytro camera with a serial port soldered onto one

Unlocking Hidden Features Of An Unusual Camera

January 25, 2023 by 65 Comments

Back in 2012, technology websites were abuzz with news of the Lytro: a camera that was going to revolutionize photography thanks to its innovative light field technology. An array of microlenses in front of the sensor let it capture a 3D image of a scene from one point, allowing the user to extract depth information and to change the focus of an image even after capturing it.

The technology turned out to be a commercial failure however, and the company faded into obscurity. Lytro cameras can now be had for as little as $20 on the second-hand market, as [ea] found out when he started to investigate light field photography. They still work just as well as they ever did, but since the accompanying PC software is now definitely starting to show its age, [ea] decided to reverse-engineer the camera’s firmware so he could write his own application.

[ea] started by examining the camera’s hardware. The main CPU turned out to be a MIPS processor similar to those used in various cheap camera gadgets, next to what looked like an unpopulated socket for a serial port and a set of JTAG test points. The serial port was sending out a bootup sequence and a command prompt, but didn’t seem to respond to any inputs. Continue reading “Unlocking Hidden Features Of An Unusual Camera” →

Pizza-Making CNC Machine Is The Only Tool We’ve Ever Dreamed Of

January 25, 2023 by 20 Comments

Making pizza is fun, but eating pizza is even better. Ideally, you’ll get to spend much more time doing the latter than the former. If you had a pizza-making CNC machine, that would help you achieve this goal, and thankfully, [Twarner] is working on that very technology.

The Pizza-Pizza CNC Machine is based on Marlin firmware running on a Mini RAMbo 3D printer motherboard, and is a 3-axis CNC machine. At a glance, you could be forgiven for thinking it’s some kind of fancy futuristic vinyl player, but it’s actually intended to cook a tasty delicious pie. It’s a gantry-based machine that uses two tool ends, one charged with distributing sauce, and the other cheese. It’s programmed with G-code to designate areas to coat with sauce and areas to cover with cheese. It can’t create dough from scratch sadly, but instead operates using pre-manufactured pizza bases.

The current level of sophistication is low, and there are issues with cheese clogs and the general messiness of the operation. However, this doesn’t mean there’s no value in automated pizza manufacture. If anything, we want to see the more open-sauce development in this area until we end up with a pizza factory on every kitchen bench worldwide. We’ve already seen that hackers have mastered how to build a good pizza oven, so now we just need to solve this part of the equation. Video after the break.

Continue reading “Pizza-Making CNC Machine Is The Only Tool We’ve Ever Dreamed Of” →

I’ve Been Printing On The Dragon Railroad…

January 25, 2023 by 28 Comments

We know many people who put much effort into building model train setups. But [Rambros] has an entire set 3D printed, and the files are open source, so you can print your own or modify it to suit you. When we first read “complete open source ecosystem,” we thought it might have been a bit of hyperbole, but it isn’t. The S-scale set includes two locomotives, a tanker, a box car, a hopper car, and a gondola car. There are different sections of track, customizable with Fusion 360. The “Dragon Railway” takes a few mechanical parts and electronics, of course. You can see one of several videos about the system below.

You can control the whole system using Bluetooth and a smartphone. The electronics are pretty simple, consisting of an ESP32 board, some motor drivers, N20 motors, and a few miscellaneous parts. We expect it would be compatible with other off-the-shelf S scale tracks and cars, but we don’t know that for sure.

Although you’ll need Fusion 360 to customize, there are plenty of ready-made STL files if you want to get started quickly. Some of the track items, like the crossing and turnout are not customizable, anyway. One particularly  impressive item is a printed auto-coupler; while a small item, getting that to work reliably with printed parts seems like it may be the most difficult part of the whole thing.

Maybe an OLED display would be the next thing? We’ve seen other printed trains, but this seems like a real labor of love.

Continue reading “I’ve Been Printing On The Dragon Railroad…” →