Active Racing Simulator Pedal

May 17, 2023 by Danie Conradie 11 Comments

Racing virtual cars from behind a PC monitor might be cheaper than doing it in the real world, but high-end sim racing peripherals still come with high-end prices. With the increasing popularity of force-feedback pedals [Tristan Fenwick] built built an active pedal that can provide significant resistance.

[Tristan] integrated a load cell into the 3D printed pedal linkage, which is connected to a 130 W NEMA23 servo motor via a 8 mm lead screw. With constant feedback from the load cell, a simple PID controller running on an Arduino to actively adjust the pedal’s position and the amount of resistance it provides.

At ~$250 in parts, it’s a significantly more affordable than the $2300 price tag on a single Simucube pedal, which served as inspiration for this project. There are still some issues to address, such as shaky ADC readings and a lack of computing power on the Arduino, the demo video after the break looks incredibly promising. [Tristan] also notes that 300 kg is overkill and a slightly smaller servo motor would probably also work.

For more incredible simulator inspiration, check out the A-10 Warthog cockpit, a 3D printed flight sim yoke and pedals, and a tank driving simulator from before the age of computer graphics.

Continue reading “Active Racing Simulator Pedal” →

Laser Projector Built From An Old Hard Drive

May 12, 2023 by Bryan Cockfield 41 Comments

Spinning hard drives are being phased out of most consumer-grade computers in favor of faster technology like solid-state drives and their various interfaces. But there’s still millions of them in circulation that will eventually get pulled from service — so what do we do with them? If you’ve got one that would otherwise be going in the garbage, they can be turned into some other interesting devices like this laser text projector.

Even the slowest drives spin at around 5000 RPM, which is perfect for this type of application. The device works by mounting twelve mirrors, each at a slightly different angle, on a drum which is spun by the drive’s motor. Bouncing a laser off of the spinning drum results in a projection of twelve horizontal lines. By rapidly switching the laser on and off depending on which mirror it’s pointing at, the length of each line can be controlled.

Thanks to persistence of vision, that allows you to show text on the surface that the laser is projected on. At speeds this high, it took [Ben] of Ben Makes Everything quite a few iterations to get it to a usable space. From sensors that were too slow to lasers not bright enough to 3D prints that were not accurate enough, he goes through the design of his build and the process in excellent detail.

After solving all of the problems including building his own constant-current laser power supply, and burning up a few laser diodes in the process, [Ben] has a laser projector capable of displaying readable text at a great distance which is also portable, running on a 12 V power supply. There are some possible areas of improvement that he notes as well, such as an unbalanced 3D printed part causing a bit of a wobble and the Arduino controller not being fast enough for more text. But it’s an impressive project nonetheless, similar to a two-mirror version we saw some time ago but with the ability to display text as well.

Continue reading “Laser Projector Built From An Old Hard Drive” →

Hackaday Prize 2023: Bolt Bot Micro Servo Droids

May 9, 2023 by Dave Rowntree 1 Comment

This Hackaday prize entry from [saul] is the beginning of a reconfigurable kit of 3D printed parts and servo motors for robotics learning. With just access to a printer, a few cheap-as-chips servo motors, an Arduino, and some nuts and bolts, you could be hacking together robot walkers within a few hours of starting!

Bolt Bots is very simple to understand, with all the mechanics and wiring out there in the breeze, but strictly for indoor use we reckon. If you want to add remote control to your application, then drop in one of the ubiquitous nRF24L01 boards and build yourself a copy of the remote control [saul] handily provides in this other project.

There really isn’t a great deal we can say about this, as it’s essentially a build kit with quite a few configuration options, and you just have to build with it and see what’s possible. We expect the number of parts to proliferate over time giving even more options. So far [saul] demonstrates a few flavors of ‘walkers’, a rudimentary ‘robot arm’, and even a hanging drawbot.

The bolt hardware can be found in this GitHub repo, and the remote control code in this second one.

Servo-based designs are sometimes sneered at due to their dubious accuracy and repeatability, but with a little of effort, this can be vastly improved upon. Also, multi-legged walkers need multiple servos and controllers to drive ’em. Or do they?

Continue reading “Hackaday Prize 2023: Bolt Bot Micro Servo Droids” →

Arctos Robotics: Build A Robot Arm Out Of 3D Printer Spares?

May 8, 2023 by Dave Rowntree 11 Comments

ARCTOS is a 6-DOF robot arm based upon 3D printed mechanics running a modified version of GRBL firmware. Let’s get this straight now, the firmware is open source, but the hardware plans are a paid download, but for less than forty euros, we reckon the investment would be well worth it, judging from the quality of the build instructions and the software support already in place. Continue reading “Arctos Robotics: Build A Robot Arm Out Of 3D Printer Spares?” →

Soldering Station Designed Around Batteries

April 28, 2023 by Bryan Cockfield 19 Comments

Companies now are looking to secure revenue streams by sneakily locking customers into as many recurring services as possible. Subscription software, OS ecosystems, music streaming, and even food delivery companies all want to lock consumers in to these types of services. Battery-operated power tools are no different as there’s often a cycle of buying tools that fit one’s existing batteries, then buying replacement batteries, ad infinitum. As consumers we might prefer a more open standard but since this is not likely to happen any time soon, at least we can build our own tools that work with our power tool brand of choice like this battery-powered soldering station. Continue reading “Soldering Station Designed Around Batteries” →

Testing Part Stiffness? No Need To Re-invent The Bending Rig

April 24, 2023 by Donald Papp 3 Comments

If one is serious about testing the stiffness of materials or parts, there’s nothing quite like doing your own tests. And thanks to [JanTec]’s 3-Point Bending Test rig, there’s no need to reinvent the wheel should one wish to do so.

The dial caliper can be mounted to a fixed height, thanks to a section of 3030 T-slot extrusion.

Some simple hardware, a couple spare pieces of 3030 T-slot extrusion, a few 3D-printed parts, and a dial indicator all come together to create a handy rig that will let one get straight to measuring.

Here is how it works: stiffness of a material is measured by placing a sample between two points and applying a known force to the middle of the sample. This will cause the material to bend, and measuring how far a standardized sample deforms under a known amount of force (normally accomplished by a dial indicator) is how one can quantify a material’s stiffness.

When a material talks about its Young’s modulus (E) value, it’s talking about stiffness. A low Young’s modulus means a material is more elastic, a high value means the material is more stiff. (This shouldn’t be confused with strength or toughness, which are more about resistance to non-recoverable deformation, and resistance to fracture, respectively.)

Interested in results, but don’t want to get busy doing your own testing? Someone’s already been there and done that: here’s a great roundup of measurements of 3D-printed parts, using different filaments.

3D-Printable Foaming Nozzle Shows How They Work

April 16, 2023 by Donald Papp 8 Comments

[Jack]’s design for a 3D-printable foaming nozzle works by mixing air with a fluid like liquid soap or hand sanitizer. This mixture gets forced through what looks like layers of fine-mesh sieve and eventually out the end by squeezing the bottle. The nozzle has no moving parts but does have an interesting structure to make this possible.

The fine meshes are formed by multiple layers of bridged filament.

Creating a foam with liquid soap requires roughly one part soap to nine parts air. The idea is that the resulting foam makes more efficient use of the liquid soap compared to dispensing an un-lathered goop directly onto one’s hands.

The really neat part is that the fine mesh structure inside the nozzle is created by having the printer stretch multiple layers of filament across the open span on the inside of the model. This is a technique similar to that used for creating bristles on 3D-printed brushes.

While this sort of thing may require a bit of expert tweaking to get the best results, it really showcases the way the fundamentals of how filament printers work. Once one knows the process, it can be exploited to get results that would be impossible elsewhere. Here are a few more examples of that: printing only a wall’s infill to allow airflow, manipulating “vase mode” to create volumes with structural ribs, and embedding a fine fabric mesh (like tulle) as either a fan filter or wearable and flexible armor. Everything’s got edge cases, and clever people can do some pretty neat things with them (when access isn’t restricted, that is.)