a DIY smoke grenade pours out smoke from a vape pen assembly

R/C Smoke Grenade Rolls With The Changes

March 22, 2024 by Kristina Panos 9 Comments

[Davis DeWitt] gets to do something that many of us only dream of — build cool working props for movies. This time, the director asked for a realistic smoke grenade that can roll up to a mark and stop on it every take, pouring out smoke the entire time.

[Davis] decided on a hamster ball-esque design that uses a pair of motors that he can control remotely, plus the innards from a vape pen and a tiny fan to distribute the smoke. The motors spin 3D printed wheels using printed gears attached to the shafts, which drive the whole assembly forward or backward.

In order to get everything to fit inside the printed canister, [Davis] had to use the smallest components he could find, like the Seeed Xiao SAMD21 and the DRV8833 motor driver. The whole thing is powered by a pair of 18650s, which, as you might imagine, really factored into the weight distribution scheme. In this case, the batteries act as a pendulum and keep the inner assembly level and not spinning wildly inside the canister.

Finally, it was time for the smoke grenade aesthetics. After what seemed like endless sanding, priming, and masking, [Davis] had a really good-looking smoke grenade that just needed some vinyl lettering and fake wear-and-tear to be complete. Be sure to check it out in action after the break.

We don’t see a lot of grenades around here, but when we do, they’re often keyboards.

Continue reading “R/C Smoke Grenade Rolls With The Changes” →

Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Mad Model M

July 27, 2021 by Kristina Panos 22 Comments

Hand-Wired Hell Help

Do you dream of building a curvy ergonomic keyboard or macro pad, even though the idea of hand wiring gives you nightmares? You can make it a bit less troublesome with a tiny PCB for each key switch, as long as you have a reflow oven or you’re okay with a bit of surface-mount soldering for the diode, LED, and capacitor.

As a bonus, these should make switches a bit more secure against movement, and you could probably even get away with using hot swap sockets if you wanted. [Pedro Barbero] has the Gerber files available if you want to get some fabbed. We sort of wish we had used these on our dactyl, though the case is awfully tight and they might not fit.

Ultra-Mechanical Keyboard Angles with Lifter Motors

Lots of people prefer an angled keyboard, but plenty of new keebs, especially mechanical ones, just don’t offer that at all. Well, the wait for an adjustable 75% is over, at least. Okay, that’s not exactly true. The wait for a group buy to begin for an adjustable 75% is almost over.

Nestled in between the arrow cluster and the menu key of the Besides Studios M-One is a rocker switch that angles the keyboard from 3° to 7° slowly but surely, like an adjustable bed. This is going to be a bare-bones group buy, meaning that it won’t come with any switches, stabs, or keycaps, but that doesn’t mean it will be cheap at $299. [BadSeed Tech] got an early prototype and built it out with Gateron Ink Black V2 switches in the video below in order to give it a proper spin.

Continue reading “Keebin’ With Kristina: The One With The Mad Model M” →

Robot, Sudo Fold My Laundry

July 22, 2020 by Al Williams 11 Comments

[Ty Palowski] doesn’t like folding his many shirts. He saw one of those boards on TV that supposedly simplifies folding, but it does require you to manually move the board. That just won’t do, so [Ty] motorized it to create a shirt folding robot.

The board idea is nothing new, and probably many people wouldn’t mind the simple operation required, but what else are you going to do with your 3D printer but make motor mounts for a shirt folding machine? The folding board is, of course, too big for 3D printing so he made that part out of cardboard at first and then what looks like foam board.

Continue reading “Robot, Sudo Fold My Laundry” →

Cat Robot’s Secret To Slim Legs? Banish The Motors!

September 15, 2018 by Donald Papp 6 Comments

The first thing to notice about [Bijuo]’s cat-sized quadruped robot designs (link is in Korean, Google translation here) is how slim and sleek the legs are. That’s because unlike most legged robots, the limbs themselves don’t contain any motors. Instead, the motors are in the main body, with one driving a half-circle pulley while another moves the limb as a whole. Power is transferred by a cable acting as a tendon and is offset by spring tension in the joints. The result is light, slim legs that lift and move in a remarkable gait.

[Bijuo] credits the Cheetah_Cub project as their original inspiration, and names their own variation Mini Serval, on account of the ears and in keeping with the feline nomenclature. Embedded below are two videos, the first showing leg and gait detail, and the second demonstrating the robot in motion.

Continue reading “Cat Robot’s Secret To Slim Legs? Banish The Motors!” →

A Dynamometer For Measuring Motor Power

December 18, 2017 by Jenny List 26 Comments

If you have ever ventured into the world of motor vehicles you may be familiar with a dynamometer, possibly as a machine to which your vehicle is taken for that all-important printout that gives you bragging rights (or not) when it comes to its ability to lay down rubber. A dynamometer is essentially a variable load for a rotating shaft, something that converts the kinetic energy from the shaft into heat while measuring the power being transferred.

Most of us will never have the chance to peer inside our local dyno, so a term project from a group of Cornell students might be something of interest. They’ve built a dynamometer for characterising small electric motors, and since their work is part of their degree courses, their documentation of it goes into great detail.

Their dynamometer takes the form of a shaft driving a stainless steel disc brake upon which sit a pair of calibers mounted on a fixed shaft that forms a torsion bar. The whole is mounted in a sturdy stainless steel chassis, and is studded with sensors, a brace of strain gauges and a slotted disc rotation sensor. It’s not the largest of dynamometers, but you can learn about these devices from their work just as they have.

This is a project sent to us by [Bruce Land], one of many from his students that have found their way to these pages. His lectures on microcontrollers are very much worth a look.

Hackaday Prize Entry: Modular Stepper Control

May 12, 2017 by Eric Evenchick 22 Comments

Stepper motors are a great solution for accurate motion control. You’ll see them on many 3D printer designs since they can precisely move each axis. Steppers find uses in many robotics projects since they provide high torque at low speeds.

Since steppers are used commonly used for multi-axis control systems, it’s nice to be able to wire multiple motors back to a single controller. We’ve seen a few stepper control modules in the past that take care of the control details and accept commands over SPI, I2C, and UART. The AnanasStepper 2.0 is a new stepper controller that uses CAN bus for communication, and an entry into the 2017 Hackaday Prize.

A CAN bus has some benefits in this application. Multiple motors can be connected to one controller via a single bus. At low bit rates, it can work on kilometer long busses. The wiring is simple and cheap: two wires twisted together with no shielding requirements. It’s also designed to be reliable in high noise environments such as cars and trucks.

The project aims to implement an API that will allow control from many types of controllers including Arduino, Linux CNC, several 3D printer controllers, and desktop operating systems. With a few AnanasSteppers one of these controllers, you’d be all set up for moving things on multiple axes.

KFC Winged Aircraft Actually Flies

April 14, 2017 by Jack Laidlaw 41 Comments

[PeterSripol] has made an RC model airplane but instead of using normal wings he decided to try getting it to fly using some KFC chicken buckets instead. Two KFC buckets in the place of wings were attached to a motor which spins the buckets up to speed. With a little help from the Magnus effect this creates lift.

Many different configurations were tried to get this contraption off the ground. They eventually settled on a dual prop setup, each spinning counter to each other for forward momentum. This helped to negate the gyroscopic effect of the spinning buckets producing the lift. After many failed build-then-fly attempts they finally got it in the air. It works, albeit not to well, but it did fly and was controllable. Perhaps with a few more adjustments and a bit of trial and error someone could build a really unique RC plane using this concept.

Continue reading “KFC Winged Aircraft Actually Flies” →