No Secret Knocks Required At [Steve’s] House – Your Subway Pass Will Do

August 22, 2012 by Mike Nathan 26 Comments

rfid-door-lock

[Steve] is often host to all sorts of guests, and he was looking for an easy way to let his friends come and go as they please. After discovering that his front door came equipped with an electronic strike, he decided that an RFID reader would be a great means of controlling who was let in, and when.

Giving all your friends RFID cards and actually expecting that they carry them is a bit of a stretch, but lucky for [Steve] he lives near Boston, so the MBTA has him covered. Just about everyone in town has an RFID subway pass, which pretty much guarantees that [Steve’s] cohorts will be carrying one when they swing by.

He crafted a stylish set of wooden boxes to contain both the RFID reader and the Arduino that controls the system, matching them to the Victorian styling of his home. A single button can control the setup, allowing him to add and remove cards from access lists without much fuss. For more granular control however, [Steve] can always tweak settings from the Arduino serial console.

The card system is both stylish and useful – a combination that’s hard to beat.

Summer Vacation Home For The Indoor Cats

August 20, 2012 by Mike Szczys No comments

Throw your indoor cat a bone (or a tuna steak as it were) this year by building them a summer vacation spot. Since [Travis Brown] lives on a busy street he worries that his cat would get hit by a car if allowed to roam outside. He and a friend found a suitable alternative with this outdoor cat enclosure.

The centerpiece of the build is a platform that overlooks the back yard. It’s got a couple of different levels which lets the cat see over the deck railing, and provides a bit of shade from the sun during the day. Chicken wire encloses the entire structure to make sure our feline friends don’t go off on their own, but the gang-plank that connects the platform to the house lets them decide when to go outside or come back in. The entrance to the house is an open window covered with plywood and fitted with a cat door. This is a nice touch since the cat door can be locked to keep them in a night.

Between this for summer and the heated bed for winter you’re going to have the most spoiled cat on the block.

Washing Machines That Do It Without Electricity

August 16, 2012 by Mike Szczys 26 Comments

Those of us living in the first world take clean clothes for granted. Throw them in the washing machine, transfer to the dryer after 45 minutes, and you won’t smell for another two weeks or so. But for people living in areas without electricity, clean clothes are a huge amount of work. Hand washing a family’s clothes is estimated at 6 hours per day, three to five days per week. Here’s a post that looks at some of the different human-powered washing machines out there.

We’ve built our own human-powered machine before using a five-gallon bucket with a hole in the lit to receive the handle of a toilet plunger which acts as an agitator. But that pales in comparison to some of the machines seen here. The concept we like the most is shown above. It’s an MIT project being used at an orphanage in Peru. The bicycle lets you easily power the spinning basket inside of the drum. The rear derailleur has been mounted on the axle so that the rider has a wider range of gears when spinning heavy loads. Take a look at the post linked above to see all of the offering, but we’ve also embedded video of two of them after the break.

If you were looking for a washing-machine powered bike instead of a bike-powered washing machine you’ll want to head on over to this post.

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Cat Palace With An Automatic Heat Lamp

August 16, 2012 by Mike Szczys 35 Comments

[Herpity] was getting tired of his cat manipulating him into turning on a lamp above her bed every time she wanted a nap. She likes the warmth put off by the light bulb but he knew he could do better than that so he built a bed which includes an automatic heat lamp. To help introduce her to the new enclosure he set it on the chair where she normally naps.

The bed has two parts, the lower chamber acts as the sleeping area. There is a false bottom underneath the blanket which acts a platform for the weight sensors which detect when the cat is ready for a nap. A PIC microcontroller monitors two sensors and switches on mains voltage to a heat lamp once the pre-calibrated weight threshold has been reached. The upper part of the enclosure holds all of the electronic components and makes room for the recessed light housing. [Herpity] included an exhaust fan for the upper chamber but it turns out a grating is all he needs to keep the temperature at an acceptable level.

[via Reddit]

Toothbrush Timer

August 15, 2012 by Mike Szczys 4 Comments

This toothbrush holder will make sure you’re brushing your pearly whites for an appropriate length of time. The three cups serves as tootbrush storage, and detect when one has been removed. Once you start brushing your teeth the lights on the front and bell in the back count down the process automatically.

The counting sequence starts when a weight sensor in the base detects a change caused by picking up a toothbrush. The ATmega328 — which is programmed with Arduino-style code — then turns on all of the incandescent lamps mounted on the front portion of the base. Each of these are switched with a 2N3904 transistor in order to sink enough current for the bulb. As a two-minute timer decrements, the bulbs are extinguished one by one. But there is also an auditory feedback mechanism. On the back of the base is a small bell. A hammer on a servo strikes the bell every 30 seconds to let you know how you’re doing. The entire thing is driven by an internal Li-ion battery which lasts about three weeks between charges. Don’t miss the demo video found after the break.

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Southwest Tour: Scrap Tattoo Gun

August 13, 2012 by Caleb Kraft 18 Comments

I had an idea for keeping things interesting on this long road trip through the southwest. I was going to gather a few bits from each hackerspace and build something using minimal tools while we were driving down the road. I settled on the idea of a really simple “jailhouse” tattoo gun. I knew I could build one from parts I could source very easily and that I wouldn’t need much in terms of tools to make it happen.

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ReactionWare 3D Printed Medicine

August 5, 2012 by Richard Steele 33 Comments

The University of Glasgow has released a Chemistry research paper covering the applicational process of printing pharmaceutical compounds.

Yes thats correct actually printing medication. Using various feedstock of chemicals they see a future where manufacturing your medication from home will be possible. Using standard 3D printing technology it is possible to assemble pre-filled “vessels” in such a way that the required chemical reactions take place to produce the required medication. This will be like having a minature medication manufacturing facility in your home. The possible implications of this could be far reaching.

There would need to be a locked down software etc or certain chemcials restrictions to prevent the misuse of this technology. Prof [Lee Cronin], who came up with the paper’s principal has called this process “reactionware”

Professor [Cronin] found, using this fabrication process, that even the most complicated of vessels could be built relatively quickly in just a few hours.

[via boingboing] Continue reading “ReactionWare 3D Printed Medicine” →