Adding a Manual Z-axis To Your Laser

DSC07543 (Custom)

[Martin Raynsford] sells lasers, and laser cuts stuff for a living — we’re kinda jealous. Anyway, laser cutters from China are great, but sometimes lack certain functionality, so he decided to add his own z-axis feature!

The main laser cutter he uses has a very slow z-axis, and it’s also difficult to control — a job can’t be paused to adjust the height offset, the datum must be set every time manually, and you have to be in the very top level of the menu in order to do anything with it! With this in mind, [Martin] decided to add his own z-axis control, completely separate from the laser’s on board control system.

He’s using an Arduino Pro Mini to control the stepper motor with PWM. His new controller has four buttons — fast and slow, in each direction. He’s used the original end stops to protect the axis, and he’s also added a feature to set a datum by holding down both fast and slow buttons at the same time. It ended up being a very cheap upgrade to his system, and he’s also shared the source for anyone looking to recreate it.

[Read more...]

Black Orb Just Wants Someone To Talk With

spaceReplay

A team at the Royal College of Art has created Space Replay, a floating black orb that records and plays back conversations from passers-by. Space Replay is a neutrally buoyant helium balloon carrying a small payload. An Arduino, an Adafruit Wave Shield, and a small speaker make up the balloons’ brain. The team used the waverp library to record and play back sounds through their shield. 3 lithium coin cells power the system. A small vacuum formed plastic housing keeps all the internal parts together, as well as acts as a small speaker cone to amplify sounds entering and leaving the orb.

As the video shows, the final result is rather creepy. A slight breeze in a subway station caused the orb to move slowly down the hallway. One would think that space replay would freak a few people out, or at least entice the curious to touch it. Other than one amused elevator rider, the unflappable London public paid no mind to it. Maybe if it had some tea…

[Read more...]

Ask Hackaday: Wiping Your Bum With An Arduino?

TP

Over or under? Standing or sitting? Truly, toilet paper has been the focus of the most irreconcilable arguments ever. The folks on the Arduino Stack Exchange have a far more important question: how do you trigger an alarm when your TP supply is low?

[user706837] asked the Internet this question in response to his kids never replacing an empty roll. This eliminates the most obvious means of notifying someone of an empty roll – looking at it before you sit down – and brings up a few interesting engineering challenges.

Most of the initial ideas deal with weight or some sort of light sensor that can differentiate between the white TP and the brown roll. A much, much more interesting solution puts a radioactive source in the TP holder’s spring-loaded rod and uses a sensor to detect how much TP is left. A quick back-of-the-wolfram calculation suggests this might be possible, and amazingly, not too dangerous.

We’re turning this one over to you, Hackaday readers. How would you design an empty toilet paper alarm? Bonus points awarded for ingenuity and cat resistance.

Image source, and also one of the longest and most absurd Wikipedia articles ever.

A Cocktail Shaker With Android And Arduino

drinks

The most rewarding part of any project must be sitting down to see the fruits of your labors set in action for the first time and relaxing with a nice drink. [Tony DiCola] is really showing off his ability to think ahead, because his smart cocktail shaker takes care of the post-build celebration, measuring out drinks with exacting precision.

The build measures out precise amounts of any liquid with the help of a small electronic scale [Tony] picked up from Harbor Freight. Instead of trying to interface with the electronics in the scale, he instead connected a INA125 instrument amplifier to the load cell. An Arduino micro measures the weight on the load cell, and with the known densities of gin, vermouth, and Kahlua, [Tony] can get a very good idea of how much liquid is in the cocktail shaker.

The really neat part of this build is the interface: [Tony] wrote an Android app for his tablet that talks to the Arduino with an Adafruit Bluefruit Bluetooth adapter. The app receives the current weight on the load cell, displays the current amount of liquor in the cocktail shaker, and provides step-by-step instructions for making any cocktail.

It’s a handy little device to keep around the liquor cabinet, and with an absurd amount of pumps and valves could easily become the basis for a very cool cocktail bot.

[Read more...]

Turning A Router Into An Arduino Yún

yun

The Arduino Yún was the first of a new breed of Arduinos that added a big honkin’ Linux System on Chip to the familiar ATMega microcontroller and unique pin headers. It’s a surprisingly powerful system, but also very simple: basically, it’s just an Atheros AR9331 running Linux, an ATMega32u4 doing its Arduino thing, both connected by a serial connection. The Atheros AR9931 is also found in a router popular amongst hardware hackers. It really was only a matter of time before someone ported the Yun software to a router, then.

[Tony] took a TL-WR703N router and put OpenWRT on it. Turning this router into the Linux side of a Yún was a simple matter of uploading the Yún software to the root directory of the router and rebooting it. The Arduino side of the Yún is handled by an Arduino Mega connected to the USB port of the router. A quick update to Arduino’s boards.txt file, and a hacked together Yún is just a strip of duct tape away.

The Yún may not be extremely popular, but it does have a few interesting use cases. Maybe not enough to drop $70 on a board, but if you already have a WR703 router, this is a great way to experiment.

Thanks [Matt] for the tip.

Here’s the Dirt on Printing With Pollution

[Anirudh] and his friends were sitting around reminiscing about India. In particular, they recalled riding around in auto-rickshaws in stifling heat, watching their skin turn black from the exhaust. They started thinking about all of the soot and pollution in crowded cities the world over and wondered whether the stuff could be re-purposed for something like printer ink. That’s how they came up with their soot/pollution printer.

They created a soot-catching pump which they demonstrate with a burning candle. The pump mixes the soot particles with rubbing alcohol and an oil substrate and sends the ink to an HP C6602 inkjet cartridge. They used [Nicolas C Lewis]‘s print head driver shield for Arduino to interface with the cartridge, turning it into a 96dpi printing head that uses only five pins.

[Anirudh] and his friends plan to design a carbon separator using charged plates to capture the soot particles from pollution sources and filter out dust. Be sure to check out their demonstration video after the jump.

Update: In response to [Hirudinea]‘s comment about mining the carbon from cars, [Anirudh] is now looking for collaborators (tinkerers, filmmakers, DIY enthusiasts) to move forward with the idea of re-purposing carbon. Email him at anirudhs@mit.edu.

 

[Read more...]

A Low Cost Arduino FPGA Shield

ardu-fpga

[technolomaniac] is kicking butt over at Hackaday Projects. He’s creating a low cost Arduino based FPGA shield. We’ve seen this pairing before, but never with a bill of materials in the $25 to $30 range. [technolomaniac's] FPGA of choice is a Xilinx Spartan 6. He’s also including SDRAM, as well as an SPI Flash for configuration. Even though the Spartan 6 LX9 is a relatively small FPGA, it can pack enough punch that the Arduino almost becomes a peripheral. The main interconnect between the two will be the Arduino’s ability to program the Spartan via SPI. Thanks to the shared I/O pins though, the sky is the limit for parallel workflow.

[technolomaniac] spent quite a bit of time on his decoupling schematic. Even on a relatively small FPGA power decoupling is a big issue, especially when high speed signals come into play. Thankfully Xilinx provides guides for this task. We have to mention the two excellent videos [technolomaniac] created to explain his design. Documenting a project doesn’t have to be hours of endless writing. Sometimes it’s just easier to run a screen capture utility and click record. As of this writing, the schematic has just been overhauled, and [technolomaniac] is looking for feedback before he enters the all important layout stage. The design is up on his github repository in Altium format. Due to its high cost, Altium isn’t our first pick for Open Hardware designs. There are free viewers available, but [technolomaniac] makes it simple by putting up his schematic in PDF format (PDF link). Why not head over to projects and help him out?

[Read more...]