Bike Trainers As Video Game Controllers

While we’ve largely settled on analog sticks and digital buttons for controlling video games, there’s all sorts of projects to create truly esoteric controllers that allow playing games in unique ways. This one from [sukolupo] lets you use data from standard bike trainers to get your virtual character moving.

Called Deck de France, it maps the data coming from one of the supported bike trainers to a virtual controller which can then be “plugged in” to a gaming console of choice, in this case a Steam Deck mounted to the trainer’s handlebars. Although a bike trainer doesn’t have the same number of inputs as a modern gaming controller, it does have enough to play games like Rocket League. As you might expect, it’s also perfect for biking titles such as the Tour de France series.

As far as unique controllers for video games go, this one is surely up in the rankings with a real trombone or a controller purpose-built for riding virtual horses. It’s also a great way for those who are getting a bit bored of riding their trainers to breathe some new life into their exercise routine. We’ve also seen some open-source alternatives for modern bike trainer software as well, which is another great way to get excited about exercise equipment too.

Stewart Platform Walker Gains Feeling In Legs From Resistors

Stewy is a very interesting robot, with some slightly odd kinematics. Its head is a Stewart platform, which is a common-enough 6-DOF actuated plate normally used with a fixed base. By connecting legs to the same servos running the Stewart platform, [JD] turned it into an adorable hexapod walker. The walker had a problem, though: it can’t feel its feet, and [JD] thinks that would make it much more mobile on uneven surfaces. So he got some resistors to turn the cheap servos in its legs into force-sensing actuators.

Well, almost. He’s not actually putting strain gauges or anything like that into the legs; he’s just measuring the voltage drop across a resistor in series with the servos. Since the motors draw more current the more torque they’re putting out, he has a very quick and easy way to sense the current and thus the torque using good old Ohm’s law and an analog input on the microcontroller driving the robot. It’s a simple hack, but the data he’s getting is surprisingly good for how much work it is to add to a robot, as you can see in the video — at least once he slowed down the servos a touch.

Perhaps this isn’t a ground-breaking innovation, but [JD] does a very good idea explaining it. Of course if you want to use resistors to sense force directly, force-sensitive resistors are a thing that we’ve seen in everything from Twister-mat MIDI controllers to self-leveling 3D printers.

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Open Source Stream Deck Targets Flexibility

Stream decks are very useful when you’re live on camera and you need to hit some complicated macro at a glance. However, there is sometimes a perception that commercial options are a touch expensive for what they are, an attitude which has spawned many DIY builds. [Fady Faheem] has developed just such a device of his own.

Named Stream32, the build is intended to be simple to understand and adapt to one’s own individual workflow. Putting one together is as easy as buying a display, hooking it up to an ESP32, flashing the firmware, and then adding pages of shortcuts as desired. [Fady] has designed the firmware to be flexible with regards to screen choice — currently, it can be set up for a 4″ Waveshare LCD or a nice roomy 10.1″ display from Elecrow. Since it’s open source, adapting to a wider range of displays is a potential exercise for the builder.

The great thing about custom stream decks is you have all the freedom in the world to customize them to your own specific setup. Play with the code, the functionality, the visual layout—all to suit your own needs. If you’re working on your own custom hardware, be sure to tell us on the tipsline.

Browser-based 3D Editor Covers The Basics While Staying Local

Got an idea and want to make a simple 3D model, but don’t want to install a full-fledged CAD modeling suite and queue up a few hours of tutorial videos? Check out SketchForge, a 3D modeling program that runs locally in one’s browser without any need for an account, or external services.

SketchForge takes a more WYSIWYG approach to 3D modeling by making it easy to put an object together with primitive shapes, and making it extra easy to specify dimensions and align parts with one another. There’s also a sketch feature that makes it easier to create more complex shapes by making a 2D drawing, then extruding or revolving it into a solid. We like that it has STEP format export as an option, making it easy to import your creation into another CAD program of your choice later. Most 3D printer slicers natively support the STEP format nowadays, too.

It’s a bit reminiscent of Tinkercad in concept, but entirely local. It’s still new, but there’s a demo online that gives a good idea of its capabilities if you’d like to give it a spin.

We’re reminded of CaDoodle, another project that takes the “Tinkercad, but local” approach but as a standalone executable, instead of browser-based.

Commercialization And Innovation

The last year or two has seen relatively affordable multi-material printers hit the market, and the question that [Tom Nardi] and I were kicking around when he was writing up the 2025 year-in-review article was what it was going to mean for our folks. I don’t think he got it wrong per se, but his heading for that section “Grandma is 3D-Printing in Color” only tells half the story.

He did get that part right, though. We’ve certainly seen a flourishing of multi-material designs out there that take advantage of the availability of (usually) four colors. The ability to print in color has given life to the purely decorative models, of course. Think full-color Pokemon desktop toys, for instance. But even functional prints have benefited from contrasting color labels printed right into the box, not to even mention the multi-material supports that pull off easier and cleaner than ever before.

Since most of these multi-filament machines are pretty much locked down as far as hardware tinkering goes, our sights were firmly locked on what the end-user would do with the new capability. But we overlooked the third axis of 3D printering: the software hackers. And it’s precisely in this area of slicer and path-planning that we’ve seen some of the coolest developments this year. Why? Because people have the hardware in their hands that they need to test out the algorithms.

FullSpectrum and the more recent ImageMap are two techniques to get the missing in-between colors out of a four-filament printer, and in particular ImageMap tries to get the job done faster, and with fewer purges. We are amazed to see two different approaches to color blending popping up in just a few months of each other, and we have no doubt that work on this is going to continue.

At the end of the day, this really is just “put new tools in the hands of creative hackers, and they’ll find new ways to use them”, so we shouldn’t have been surprised at all. But if this is what comes out of the commercialization of the multi-material printer, what’s going to come when some of the more esoteric machine designs go mainstream? We can’t wait to find out!

Testing A 3D Printed Cycloidal Gearbox Design

Cycloidal gearboxes are a recurring theme in the hobbyist space due to the performance they promise in a compact package. They are capable of taking in a high-speed input and reducing it down to a set ratio with very low backlash, which theoretically makes them perfect for a wide range of projects where size and weight matter. Correspondingly, [Advanced Hobby Lab] has been tinkering with a 3D printed design to fit on NEMA 17 stepper motors.

For [Advanced Hobby Lab] the primary goal was to check that his cycloidal gearbox design was a real improvement over the planetary gearbox alternative. Although the 3D printed cycloidal drive worked well enough, some testing put real numbers to it, including a 92% efficiency. The gearbox also adds some noise over the stepper motor, but less so than the 3D printed planetary gearbox.

Of course, all of this is within the limits of FDM 3D printing and with a few metal parts, so there’s always room for improvement, but in the world of hobbyist 3D printed gearboxes it’s not a bad showing. The print and project files are available for anyone who is also feeling the itch. Of course, you can also opt for the dual-nested cycloidal design that we recently featured, as it promises to be even more compact, have even fewer parts and smoother action.

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A Compact Game Controller For Your Phone

[Gil Yankovitch] noted that playing games on a touchscreen phone gave up a certain something in terms of the tactile feedback one gets from real buttons. To that end, he was inspired to build a controller specifically for phones that solved this very problem.

The result was JoyFon. It’s a small gamepad built around the Raspberry Pi Pico, and can be put together around an RP2040 or an RP2350 as desired. It has four face buttons, a directional pad, and start and select buttons, as well as additional shoulder buttons up top in later revisions.

The JoyFon enumerates as a standard USB HID gamepad, so you could use it to play games on just about any PC, laptop, or tablet. However, the JoyFon is specifically designed for use with smartphones in the vertical orientation. This guided the design of the 3D printed enclosure, which positions the USB-C port to plug into the base of a phone, such that the buttons sit neatly beneath it. It does cover some of the phone screen, but that’s not always a problem when playing emulated games with a 4:3 or similar aspect ratio. The result is a button and screen layout not dissimilar to that of the original Game Boy handhelds.

We’ve seen some other great custom controller builds over the years, like this fantastic design using keyswitches.

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