Controlling A Micro Helicopter with a PS2 Controller

The Syma S107G is a venerable stalwart of the micro helicopter market. Affordable, robust, and ubiquitous, the S107G relies on infrared to receive its control signals. Emboldened by the prior work of others, [Robert] set out to control his with a Playstation 2 controller.

In this project, [Robert] is standing on the shoulders of giants, so to speak – we’ve seen others reverse engineer the S107G’s communications protocol before. [Robert] combined the efforts of several others to understand how to send commands to the helicopter, including use of two separate channels for controlling two at once.

With the knowledge of the necessary protocols, it’s then a matter of hooking up 3 LEDs in a somewhat unconventional series arrangement with a 9 volt supply, to be switched by an Arduino hooked up to a computer. A Javascript application running on the computer reads the state of a Playstation 2 controller, and spits it out over serial to the Arduino, which flashes the LEDs.

It’s not the neatest, most lightweight way of building a new controller for your remote control toy, but it does show how quickly one can throw together a project in a weekend by combining modern hardware and software tools. Plus, it’s a great learning experience on a platform that’s been experimented with the world over.

Simulating Snakes and Ladders for Fun, Not Profit

A great many of you will remember the game of Snakes and Ladders from your youth. It’s a simple game, which one grows to realise involves absolutely no skill – it’s purely the luck of the dice. [Alex Laratro] noticed that without player decisions to effect the outcome, the game was thus a prime candidate for simulation. 

[Alex] wanted to dive into the question of “Who is winning a game of Snakes and Ladders?” at any given point in the gameplay. A common approach would be to state “whoever is in front”, but the ladders might have something to say about that. [Alex] uses Markov analysis to investigate, coming to some interesting conclusions about how the game works, and how this compares to the design of more complex games like Mario Kart and Power Grid.

Overall, it’s a breakdown of a popular game that’s simple enough to really sink your teeth into, but has some incredibly interesting conclusions that are well worth considering for anyone designing their own board games. We love seeing math applied to novel and fun problems – and it can solve important problems, too.

Using 3D Printing To Speed Up Conventional Manufacturing

3D printers, is there anything they can’t do? Of course, and to many across the world, they’re little more than glorified keychain factories. Despite this, there’s yet another great application for 3D printers – they can be used to add speed and flexibility to traditional manufacturing operations.

A key feature of many manufacturing processes is the use of fixtures and jigs to hold parts during machining and assembly operations. These must be developed before manufacturing begins and must be custom made to suit the given application. Many manufacturers outsource the development of such fixturing, even in large operations – even major automakers will often outsource development of fixtures and new process lines to outside firms. This can have major ramifications when changes need to be made, introducing costly delays. However, 3D printers can be used to rapidly iterate fixturing designs to suit new parts, greatly reducing development time. As stated in the article, Louis Vuitton uses this to great effect – the reduced time of development is incredibly useful when changing manufacturing lines every few months in the fashion industry.

Obviously there are limitations – in a factory producing large steel castings, it’s unlikely a FDM-printed fixture will be much use when it comes to the wear and tear of machining hundreds of castings a day. However, as a development tool, it can prove very useful. What’s more, jigs for light industrial work – think electronics assembly, woodworking glue-ups, or any form of delicate work by hand – need not be as robust. Lightweight, readily produced 3D printed parts may be just the ticket.

Another great benefit of 3D printing is its ability to be used for mockups. You may be designing a product that requires several aluminium parts to fit together, but alas – the parts won’t be ready for weeks. Rather than wait all that time, only to find out something doesn’t fit right, it may be advantageous to print out a plastic version of the parts. Being able to check geometry with actual parts is often very useful, and makes a great tool if you need to present your work to others. It’s much easier to communicate an idea to people if they can hold and touch what you’re talking about!

It’s something worth considering if you’re setting up any sort of small production line – perhaps you’re looking for a way to make populating a run of PCBs faster, or ease the assembly of a series of distributed sensor modules. These techniques may prove particularly useful if you consider yourself a scrappy hacker.

[Hat tip to George!]

Hackaday Prize Entry: Crop Data For Improved Yields

As the world’s population continues to increase, more food will be needed for all the extra mouths to feed. Unfortunately, there’s not a whole lot of untapped available farmland. To produce extra food, crop yields need to increase. [Vignesh Ravichandran] is tackling this with the Farmcorder – a device for detecting crop nutrition levels.

The device centers around using spectroscopy to measure the chlorophyll content of leaves. This information can then be used to make educated decisions on the fertilizer required to maximize plant yield. In the past, this has been achieved with expensive bespoke devices, or, at the other end of the spectrum, simple paper color charts.

[Vignesh]’s project takes this to the next level, integrating a spectroscopy package with a GPS and logging over the GSM mobile network. This would allow farmers to easily take measurements out in the field and log them by location, allowing fertilizer application to be dialed in on a per-location basis.  The leaf sensor package is particularly impressive. Relying on a TSL2561 sensor IC, the samples are lit with 650nm and 940nm LEDs. The sensor readings can then be used to calculate the chlorophyll levels in the leaves.

It’s a project that sets out to tackle a serious world problem and uses off-the-shelf parts and some hacker know-how to do so. We hope to see this hardware on farms across the world in the near future!

No-Solder Breadboarding for SMD LEDs

Breadboarding is a great way to get started with electronics, and with the wide availability of those little wire jumpers, it’s never been easier – until you hit roadblocks due to poor connections and parasitic capacitance futzing with your signals. However, in today’s current climate, the latest and greatest modules are too often available only in SMD packages, and while breakout boards can help, it’s probably overcomplicating things a bit when it comes to SMD LEDs. It’s all good, though – [Simon Merrett] has a workaround, as part of his Yapolamp project.

[Simon] first took a flat strip of steel, and placed two neodymium magnets on top. The assembly was then wrapped in electrical tape for insulation, and two contacts were created with copper tape. The LEDs were then placed across the two contacts and wires were attached to join them to the breadboard. The 5630 LEDs [Simon] must contain some sort of ferrous material, because they were attracted to the magnets and sat neatly in place.

It’s a neat hack that would be particularly useful if you needed to quickly swap out LEDs, and saves them from damage by soldering. Meanwhile, check out this SMD LED matrix from 2009. 

RADAR Controlled Speakers

[Scott] had a simple problem – he was tired of leaning over his work bench to change the volume on his speakers. He desired a system that would readily allow him to switch the speakers on and off from a more comfortable distance. Not one to settle for the more conventional solutions available, [Scott] whipped up a RADAR-activated switch for his speaker system.

The build relies on a surprisingly cost-effective RADAR module available off the shelf, running in the 5.8GHz spectrum. At under $10, it’s no big deal to throw one of these into a project that requires some basic distance sensing. [Scott] decided to keep things simple – instead of going with a full-fat microcontroller to control the speakers, a 74HC590 IC was used to create a latch. Each time the RADAR module senses an object in close proximity, it toggles the state of the latch. The latch then controls a transistor that switches the power for the speakers.

Overall it’s a build that combines a modern integrated RADAR module with some very simple control logic to create a functional build. Of course, there’s so much more you can do with some 74-series logic. Video after the break.

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We Dig This LEGO Excavator Conversion

[Frank] was lucky enough to score a bucket wheel excavator LEGO set as a birthday present, and we won’t lie – we’re jealous. However, out of the box, the kit is somewhat limited; there is only one motor to animate the entire machine and it can’t be fully remote controlled. But don’t worry — [Frank] set out to change that (Google Translation).

The first part of the build was to add motors to control the different functions of the excavator. One motor was added for each of the two tracks to allow the machine to drive forwards, backwards, and turn. Two more motors were added to raise and lower the digging buckets, and spin the tower. Finally, the original motor was left in place to turn the conveyor.

With that done, [Frank] then used a Raspberry Pi 3 to control all the hardware, being sure to house the new electronics in LEGO for an original look. The Raspberry Pi might be a lot of muscle to simply control a few motors, but it made it quick and easy for [Frank] to implement a Wiimote as a controller over Bluetooth. You can check out a couple demo videos in his most recent update.

It’s a great project, and we’d love to see the Raspberry Pi put to good use by allowing control over the Internet so we can dig in the sand over lunch breaks. We’ve seen some great LEGO hacks before, like this method of modifying cheap gear motors to work with LEGO parts.