Making Funhouse Mirror Lenses

[Robb] has had a little experience making lenses from scratch. His first attempt was for a DIY projector, and while the lens was a little blurry, it did work rather well for something carved out of a block of acrylic. Now he’s taking his experiments with lenses even further with DIY optics that turn everything into a funhouse mirror.

There were two techniques tested while making these lenses. The first was the old standby, CNC milling. A piece of acrylic was put in a CNC and carved with a 1/2″ ball mill. The second technique was 3D printing on a very fancy and very expensive Objet Connex 500. Neither of these methods produce a ready to use lens; to get a finished lens out of the machined or printed objects, [Robb] had to wet sand with 240, 320, 400, 600, 1000, 1500, and 2000 grit sandpaper. After a few hours worth of sanding, the parts were polished with a scratch remover.

Making a lens like this isn’t really that novel – it’s basically the same way lenses have been made for 500 years. The real trick here is making funhouse mirror style lenses. These lenses were created by raytracing in Rhino and Neon. It’s tricky; the index of refraction for acrylic is a little lower than glass, and the refraction for 3D photoresin is a bit higher than glass.

With those models in hand, it’s a relatively simple matter of making some very cool and very strange lenses.

Play Robotic Bongos using your Household Plants

[Kirk Kaiser] isn’t afraid to admit his latest project a bit strange, being a plant-controlled set of robotic bongos. We don’t find it odd at all.  This is the kind of thing we love to see. His project’s origins began a month ago after taking a class at NYC Resistor about creating music from robotic instruments. Inspired to make his own, [Kirk] repurposed a neighbor’s old wooden dish rack to serve as a mount for solenoids that, when triggered, strike a couple of plastic cowbells or bongo drums.

A Raspberry Pi was originally used to interface the solenoids with a computer or MIDI keyboard, but after frying it, he went with a Teensy LC instead and never looked back. Taking advantage of the Teensy’s MIDI features, [Kirk] programmed a specific note to trigger each solenoid. When he realized that the Teensy also had capacitive touch sensors, he decided to get his plants in on the fun in a MaKey MaKey kind of way. Each plant is connected to the Teensy’s touchRead pins by stranded wire; the other end is stripped, covered with copper tape, and placed into the soil. When a plant’s capacitance surpasses a threshold, the respective MIDI note – and solenoid – is triggered. [Kirk] quickly discovered that hard-coding threshold values was not the best idea. Looking for large changes was a better method, as the capacitance was dramatically affected when the plant’s soil dried up. As [Kirk] stood back and admired his work, he realized there was one thing missing – lights! He hooked up an Arduino with a DMX shield and some LEDs that light up whenever a plant is touched.

We do feel a disclaimer is at hand for anyone interested in using this botanical technique: thorny varieties are ill-advised, unless you want to play a prank and make a cactus the only way to turn the bongos off!

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Caption CERN Contest Week 11

Week 10 of the Caption CERN Contest is a wrap folks! Our surprised scientist brewed up a ton of great captions from our great community. We may never know what exactly is in that keg/carboy, or what the heck is draining into that bucket. Still, it’s probably safe to say that no one has put this much thought into those particular items since this scientist performed his research.

The Funnies:

  • “After many decades of hard work, Dr. Milton and his research was moved down into basement after he complained one too many times about his missing stapler.” – [joe_pumpernickle]
  • “Parker! Get down here! Ever since that radioactive spider bit you, you’ve crawling up the walls!”-[DainBramage]
  • “It rubs the dielectric grease on its relay contacts or else it gets the hose again” -Team effort from [MechaTweak] and [Nick Sayer]

The winner for this week is [airbuckles] with “Meet Dooglas, experimenting with beer brewing, CERN style. Shown here controlling the critical HOP collider.” [airbuckles] won’t need any buckles for his new Robot T-Shirt From The Hackaday Store!

Week 11: A double-header!

cern-11-smWe’ve got something a bit different for week 11: Two images from CERN’s archives! Both of these images feature a lovely PDP-11 from Digital Equipment in Galway, Ireland. They also feature two CERN researchers. The scientist on the left is wearing typical hacker attire – sneakers, jeans, and a comfy shirt. The hacker on the right went for something which we’re guessing was a bit more stylish back in 1982, but hasn’t quite held up to the test of time.

These scientists must have been doing some heavy-duty number crunching to need a PDP-11. Do you know what that strange hand wired rack of equipment is in the center? Do you have any idea where we can find a pair of harem pants like the woman on the left? Write a caption and let us know!

Add your humorous caption as a comment to this project log. Make sure you’re commenting on the project log, not on the project itself. As always, if you actually have information about the image or the people in it, let CERN know on the  original left CERN image, and original right CERN image.

Good Luck!

The Possibility Of Driving 16,000 RGB LEDs

Like just about everyone we know, [Luis] decided a gigantic RGB LED matrix would be a cool thing to build. Gigantic LED matrices are very hard to build, though: not only do you have to deal with large power requirements and the inevitable problems of overheating, you also need to drive a boat load of LEDs. This is not easy.

[Luis] found a solution to the problem of driving these LEDs with a new, fancy ARM Cortex M4 microcontroller. All Cortex M4 ARMs have DMA, making automatic memory transfers to peripherals and LED strips a breeze.

The microcontroler [Luis] is using only supports 1024 transfers per transfer set, equating to a maximum of 14 LEDs per transfer. This problem can be fixed by using the ping-pong mode in the DMA controller by switching between data structures for every DMA request. Basically, he’s extending the number of LEDs is just switching between two regions of memory and setting up the DMA transfer.

The result is much better than [Luis]’ original circuit that was just a bunch of SPI lines. It also looks really good, judging by the video below. It’s not quite a gigantic LED matrix yet, but if you want to see what that would look like, check out the huge 6 by 4 foot matrix hanging in the Hackaday overlord office.

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RadioShack Demise Could Signal the Rise of Mom-and-Pop

No matter how you feel about RadioShack, for many hackers it was the one place that components could be sourced locally. Upon hearing that the stores are being shuttered (at least for those seeking non-cellphone items) we wondered if someone would rise to meet the maker market. The answer may actually be mom-and-pops — independent stores owned by people passionate about hacking and making.

tinker-and-twist-boothAt SXSW Create in March the Hackaday booth was right next door one such establishment. [Martin Bogomolni] is hard at work launching his brick and mortar store called Tinker & Twist. In the video below he speaks briefly about the concept of the store, which focuses on curating the best products and tools available and stocking them locally.

The store will be located in a shopping mall in Austin, Texas. But it takes about 100 days launch a storefront considering the permits and build-out. [Martin] decided to take the store to the hackers by exhibiting (and selling products) at SXSW Create. How else would you do this than by building a store-front as your booth? The store’s sign was CNC routed from rigid foam, and combined with a set of columns and storefront window. We stopped by late on the last day of the event and they had been having a great weekend. What started as a very well stocked set of shelves looked nearly bare.

Tinker & Twist is just the most recent in a growing trend of standalone stores focusing on hackers and makers. Our friends at Deezmaker in Pasadena, CA gave us tour last year. They’ve married the concepts of hackerspace, small-run manufacturer (in the form of their 3D printers), and retail store all-in-one. These types of examples make us quite happy — it’s been years since RadioShack was tightly focused on those actually building things. We hope to see more stores like Tinker & Twist up and running to support and enhance hacker communities everywhere.

We Have a Problem: Health Care Where There Are No Health Care Workers

Hackaday, we have a problem. There are a lot of people on this earth and not a lot of health care workers. Let’s use our skills to help alleviate this problem. What can we do to give medical professionals a wider reach, to bridge the distances between hospital and patient, and make it easier for bystanders to administer lifesaving care.

Scope of the Problem

We’d wager that your most recent and vivid remembrance of a health care worker shortage is the Ebola outbreak in West Africa. The shortage of trained professionals and supplies certainly compounded the situation in the countries worst hit. But it didn’t create the problem. Check out this list of doctors per 1,000 people (sorted lowest-to-highest with 2010 numbers). The three countries hit hardest by the outbreak — Guinea, Liberia, and Sierra Leone — register a whopping 0.0 doctors for every 1000 people. Yeah, that’s years before the outbreak.

Keep scrolling down and you’ll see that this isn’t limited to one geographic location. All over the world there are low numbers, with India and Iraq both at 0.6, and interestingly Cuba and Qatar topping the list at 6.7 and 7.7 respectively.

This isn’t a statistics post so let’s pivot. The point is made that we’re a large world population. What kind of engineering solutions can we wield to help provide everyone with the care they need? Leave your comments below but also considered entering the Hackaday Prize with them. Write down your idea as a project and tag it 2015 Hackaday Prize.

Proof That We Can Do This

firstmedic-510-aedIt’s safe to say we’ve all seen engineering solve part of this problem already. Over the last decade, Automatic External Defibrillators have become ubiquitous. The life-saving hardware is designed to be used by non-doctors to save someone whose heart rhythms have become irregular. [Chris Nefcy] helped develop AEDs and one ended up saving his life. If that’s not proof that we can change the world with our builds we don’t know what is.

Pull on that thinking cap and jump into this conversation. What can we build? What problems need to be solved right now? Where should each of us be looking to make a difference in the availability of health care in the absence of the trained professionals?

The 2015 Hackaday Prize is sponsored by:

Bouncing A Ball With A Robot

A fan of kinetic projects, [Jimmy Demello] threw together a pretty cool robot that can bounce a ball back and forth between its hand(s).

Made from scraps around the house, it consists of some wood, a piece of a fishing pole, chop sticks, a single servo motor, and of course an Arduino Uno. His original plan was to make [Claude Shannon]’s juggling robot, but this is as far as he’s gotten — so far anyway.

It bounces a 2cm ball-bearing twice before catching it and passing it back again. He thinks it would be an awesome project to scale up and use basketballs, and we’d have to agree.

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