Solve: An ESP32-Based Equation Solving Calculator

October 15, 2024 by Dave Rowntree 10 Comments

We’re suckers for good-looking old-school calculators, so this interesting numerical equation-solving calculator by [Peter Balch] caught our attention. Based around the ESP32-WROOM-32 module and an LCD, the build is quite straightforward from an electronics point of view, with the main work being on the software side of things.

A custom keyboard was constructed on Veroboard using a handful of tactile switches arranged in a charlieplexing array to minimize the number of IO pins consumed. For the display, an off-the-shelf 240×320 ILI9341-based module hooked up by SPI was used. A single lithium cell was used for the power supply, connected to a USB

You don’t need much to make a usable keyboard.

charger module, but you could just as easily substitute a 3 x AA battery box. The case was designed in DesignSpark mechanical and 3D printed. It’s unclear what keyboard version they settled on; there are options for one with keycaps and one without. Regardless, a 3D-printed frame sits atop the keyboard circuit, with the graphics printed on photo paper and a protective coversheet on top. Continue reading “Solve: An ESP32-Based Equation Solving Calculator” →

3D Printed Hydrofoil Goes From Model Scale To Human Scale With Flight Controller

October 6, 2024 by Danie Conradie 5 Comments

Hydrofoils have been around for several decades, but watching a craft slice through the water with almost no wake never get old. In the videos after the break, [rctestflight] showcases his ambitious project: transforming a standup paddleboard into a rideable hydrofoil with active stabilization.

Unlike conventional electric hydrofoil boards that depend on rider skill for balance, [rctestflight] aims to create a self-stabilizing system. He began by designing a small-scale model, complete with servo-controlled ailerons and elevators, dual motors for differential thrust, and a dRehmFlight flight controller. A pair of sonar sensors help the flight controller maintain constant height above the water. The wings are completely 3D printed, with integrated hinges for flight control surfaces slots for wiring and control components. It’s better suited for 3D printing than RC aircraft since it’s significantly less sensitive to weight, allowing for more structural reinforcement. The small scale tests were very successful and allowed [rctestflight] to determine that he didn’t need the vertical stabilizer and rudder.

The full-sized version features a scaled up wing, larger servos and motors attached to an 11-foot standup paddleboard — minus its rear end — mounted on commercially available e-foil booms. A foam battery box stores a hefty LiFePO4 battery, while the electronics from the smaller version are repurposed here. Despite only catching glimpses of this larger setup in action at the end of the video, it promises an excitingly smooth lake ride we would certainly like to experience.

We’ve seen several 3D printed hydrofoils around here, but this promised to be the largest successful attempt. Don’t fail us [Daniel].

Continue reading “3D Printed Hydrofoil Goes From Model Scale To Human Scale With Flight Controller” →

See The “Pause-and-Attach” Technique For 3D Printing In Action

October 5, 2024 by Donald Papp 7 Comments

[3DPrintBunny] is someone who continually explores new techniques and designs in 3D printing, and her latest is one she calls “pause-and-attach”, which she demonstrates by printing a vase design with elements of the design splayed out onto the print bed.

The splayed-out elements get peeled up and attached to the print during a pause.

At a key point, the print is paused and one peels up the extended bits, manually attaching them to sockets on the main body of the print. Then the print resumes and seals everything in. The result is something that appears to defy the usual 3D printer constraints, as you can see here.

Pausing a 3D print to insert hardware (like nuts or magnets) is one thing, but we can’t recall seeing anything quite like this approach. It’s a little bit reminiscent of printing foldable structures to avoid supports in that it prints all of its own self-connecting elements, but at the same time it’s very different.

We’ve seen [3DPrintBunny]’s innovative approaches before with intentional stringing used as a design element and like the rest of her work, it’s both highly visual and definitely it’s own thing. You can see the whole process in a video she posted to social media, embedded below.

Continue reading “See The “Pause-and-Attach” Technique For 3D Printing In Action” →

Building A 3D Printed Scanning Tunneling Microscope

September 30, 2024 by Dave Rowntree 12 Comments

YouTuber [MechnicalRedPanda] has recreated a DIY STM hack we covered about ten years ago, updating it to be primarily 3D-printed, using modern electronics, making it much more accessible to many folks. This simple STM setup utilises a piezoelectric actuator constructed by deliberately cutting a piezo speaker into four quadrants. With individual drive wires attached to the four quadrants. [MechPanda] (re)discovered that piezoelectric ceramic materials are not big fans of soldering heat. Still, in the absence of ultrasonic welding equipment, he did manage to get some wires to take to the surface using low-temperature solder paste.

As you can tell, you can only image conductive samples

A makeshift probe holder was glued on the rear side of the speaker actuator, which was intended to take a super sharp needle-like piece of tungsten wire. Putting the wire in tension and cutting at a sharp angle makes it possible with many attempts to get some usable points. Usable, in this instance, means sharp down the atomic level. The sample platform, actuator mount and all the connecting parts are 3D-printed with PA-CF. This is necessary to achieve enough mechanical stability with normal room temperature fluctuations. Three precision screws are used to level the two platforms in a typical kinematic mount structure, which looks like the only hard-to-source component. A geared stepper motor attached to the probe platform is set up to allow the probe to be carefully advanced towards the sample surface. Continue reading “Building A 3D Printed Scanning Tunneling Microscope” →

3D Printer Swaps Build Plates To Automate Print Jobs

September 30, 2024 by Donald Papp 17 Comments

[Andre Me] has long-standing interest in automating 3D print jobs, and his latest project is automating build plate changes on the Bambu A1 Mini.

Here’s how it works: each build plate gets a sort of “shoe” affixed to it, with which attachments on the printer itself physically interact when loading new plates and removing filled ones.

When a print job is finished, custom G-code causes an attachment on the printer to wedge itself under the build plate and peel it off until it is freed from the magnetic bed, after which the finished plate can be pushed towards the front. A stack of fresh build plates is behind the printer, and the printer slips a new one from the bottom when needed. Again, since the printer’s bed is magnetic, all one has to do is get the new plate to reliably line up and the magnetic attraction does the rest.

Some methods of automating print jobs rely on ejecting the finished parts and others swap the print beds. [Andre]’s is the latter type and we do really like how few moving parts are involved, although the resulting system has the drawback of requiring considerably more table space than just the printer itself. Still, it’s not at all a bad trade-off.

Watch it in action in the two videos embedded below. The first shows a time-lapse of loading and ejecting over 100 build plates in a row, and the second shows the whole system in action printing bowls in different colors. Continue reading “3D Printer Swaps Build Plates To Automate Print Jobs” →

VR Headset With Custom Face Fitting Gets Even More Custom

September 28, 2024 by Donald Papp 7 Comments

The Bigscreen Beyond is a small and lightweight VR headset that in part achieves its small size and weight by requiring custom fitting based on a facial scan. [Val’s Virtuals] managed to improve fitment even more by redesigning a facial interface and using a 3D scan of one’s own head to fine-tune the result even further. The new designs distribute weight more evenly while also providing an optional flip-up connection.

It may be true that only a minority of people own a Bigscreen Beyond headset, and even fewer of them are willing to DIY their own custom facial interface. But [Val]’s workflow and directions for using Blender to combine a 3D scan of one’s face with his redesigned parts to create a custom-fitted, foam-lined facial interface is good reading, and worth keeping in mind for anyone who designs wearables that could benefit from custom fitting. It’s all spelled out in the project’s documentation — look for the .txt file among the 3D models.

We’ve seen a variety of DIY approaches to VR hardware, from nearly scratch-built headsets to lens experiments, and one thing that’s clear is that better comfort is always an improvement. With newer iPhones able to do 3D scanning and 1:1 scale scanning in general becoming more accessible, we have a feeling we’re going to see more of this DIY approach to ultra-customization.

The Statial-b Open Source Adjustable Mouse

September 25, 2024 by Dave Rowntree 20 Comments

Many of us are very heavy computer users, and two items that can affect our comfort and, by extension, our health are the keyboard and the mouse. We’ve covered many ergonomic and customisable keyboards over the years, but we are not sure we’ve covered a fully adjustable mouse until now. Here’s [Charlie Pyott] with their second take on an adjustable mouse, the open source, statial-b.

[Charlie] goes into an extensive discussion of the design process in the video after the break, which is a fascinating glimpse into the methods used by a professional industrial designer. The statial concept breaks the contact surfaces of the mouse into fixed and moveable sections. The moveable sections are attached to the mouse core via a pair of ball joints connected with extendible arms, allowing the surfaces to be adjusted for both position and orientation. The design process starts with 3D scanning their ‘workhorse mouse,’ a Razer Deathadder Elite. This creates a reference volume within which the statial body should fit in its minimal configuration.

The design has a fixed central core, with each button (including the central scroller) separately adjustable. The side panel with a pair of thumb buttons is also moveable. Creating a model in Rhino 3D working with the grasshopper visual programming environment [Charlies] explored the surface constraints for the base, claw, finger and vertical grip styles common among mouse users. This model was then fed into Fusion 360 for the detailed design. After completing the design, it was passed back into Rhino 3D to add lattice effects to the panel. This helps reduce weight and lets the internal LEDs shine through. The design is intended for resin printing, so you could go wild with the visuals by missing custom resins if you were so inclined.

Continue reading “The Statial-b Open Source Adjustable Mouse” →