Bike Cinema

A Pedal Powered Cinema

When the apocalypse hits and your power goes out, how are you going to keep yourself entertained? If you are lucky enough to be friends with [stopsendingmejunk], you can just hop on his pedal powered cinema and watch whatever movies you have stored on digital media.

This unit is built around an ordinary bicycle. A friction drive is used to generate the electricity via pedal power. In order to accomplish this, a custom steel stand was fabricated together in order to lift the rear wheel off the ground. A 24V 200W motor is used as the generator. [stopsendingmejunk] manufactured a custom spindle for the motor shaft. The spindle is made from a skateboard wheel. The motor is mounted in such a way that it can be lowered to rub the skateboard wheel against the bicycle wheel. This way when the rear bicycle wheel spins, it also rotates the motor. The motor can be lifted out of the way when cruising around if desired.

The power generated from the motor first runs through a regulator. This takes the variable voltage from the generator and smooths it out to a nice even power signal. This regulated power then charges two Goal Zero Sherpa 100 lithium batteries. The batteries allow for a buffer to allow the movie to continue playing while changing riders. The batteries then power the Optomo 750 projector as well as a set of speakers.

We Have A Problem: Mass Versus Local Production

Hackaday, we have a problem. We’re trying to engineer a brighter future; a task that calls for a huge mental leap. This week, instead of discussing a concrete problem, let’s gather around the digital campfire to gnaw on a thought exercise. In thinking abstractly I hope we’ll trigger a slew of ideas you can use as your entry in the 2015 Hackaday Prize in which you can win a Trip to Space or hundreds of other prizes.

Shipping Mass Produced vs. Producing Locally

This morning I was reading an interesting story about an email server that couldn’t deliver message to any ISP physically located more than 500 miles away. In that case it turns out that the limiting factor was misconfiguration and the speed of light. But it got me thinking about things we transport in bulk versus things being transported individually. I often think about the transport of finished goods and compare where we are now to the fabrication visions [Neal Stephenson] talked about in his novel The Diamond Age. In that picture of the future, it is common building blocks of matter that are delivered to every home and business and not finished goods. Interesting.

What kind of resources are consumed in local production versus centralized mass production? Is there merit in using technology to change the way we’ve always done some things? Certainly there will not be one answer for everything so let’s talk about a few examples that might be done differently.

Scenario #1: You send a greeting card with your hand-written message to your mother for her Birthday.

handwritten-message-cardThe way things work right now, you go to the store and pick out a card. You write a personal message inside, lick, stamp, and send it through the mail. The thing is, this card is probably already in a store down the street from your mother. What if you could digitize your handwritten message and have it printed on the card and delivered from a local repository? Take it a step further, assuming that these cards are bulk-printed in one central location and distributed widely, does it save any resources to decentralize the production of the cards and make production local so that the finished goods are not being transported more than 500 miles? And for those skeptics saying that you can’t add a check or cash to the card when done this way… yes you can!

Scenario #2: The meal is finished and just as you close the door to the dishwasher you hear a horrible crack as the plastic latch that holds the door closed breaks.

Recycled household appliancesStandard practice is that the part be ordered from a parts supplier (either by you or by a serviceman). These suppliers keep a stock of common parts which are well documented in a huge library of service manuals for the myriad of home appliances out there. But when you get right down to it, it’s just a little plastic bauble. Let’s assume all of these are made in a single factory in huge production runs that supply both the manufacturer and the legacy parts houses. What if instead of this you could have these parts 3D printed by a business within 500 miles of where they are needed. There are industrial-grade 3D printing techniques that produce parts strong enough to act as a replacement. Where do you come down on resource saving between the two methods?

Scenario #∞: It’s your turn to come up with an example.

We want to hear your ideas on local production versus centralized mass production. Don’t be afraid to share half-baked ideas. The entire point of We Have a Problem is to spark civil debate on issue which could lead to world-changing solutions. Help us start the idea mill and jump on to see where it takes us. Don’t forget to carry the inspiration you find into your entry for the Hackaday Prize.


The 2015 Hackaday Prize is sponsored by:

Retrotechtacular: The Diesel Story

The diesel engine was, like many things, born of necessity. The main engine types of the day—hot bulb oil, steam, coal gas, and gasoline—were not so thermally efficient or ideal for doing heavy-duty work like driving large-scale electrical generators.  But how did the diesel engine come about? Settle in and watch the 1952 documentary “The Diesel Story“, produced by Shell Oil.

The diesel engine is founded on the principle of internal combustion. Throughout the Industrial Age, technology was developing at breakneck pace. While steam power was a great boon to many burgeoning industries, engineers wanted to get away from using boilers. The atmospheric gas engine fit the bill, but it simply wasn’t powerful enough to replace the steam engine.

hot bulb oil engineBy 1877, [Nikolaus Otto] had completed work on his coal gas engine built on four-stroke theory. This was the first really useful internal combustion engine and the precursor of modern four-stroke engines. It was eventually adapted for transportation with gasoline fuel. In 1890, the hot bulb oil engine was developed under the name Hornsby-Akroyd and primarily used in stationary power plants. Their flywheels had to be started manually, but once the engine was going, the bulb that drove combustion required no further heating.

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Revolights Keep You Safe While Riding At Night

revolights_bike_headlight_taillight

Bicycling at night can be a potentially hazardous endeavor for several reasons, but primarily because well, it’s dark. Inattentive drivers, weather, and other factors aside, the most important thing you can do to keep yourself safe is to ensure that you can see and that you are seen by others.

Revolights, an invention put together by [Kent Frankovich, Adam Pettler, and Jim Houk], is an ingenious way of accomplishing both of those things. The ring-shaped system attaches to nearly any bike tire, and includes LEDs that shine like a car’s head and taillights. A magnet attached to the bike’s fork triggers the onboard microcontroller to light only 4 LEDs at a time, letting persistence of vision take care of the rest.

We think it’s a great idea, and clearly others do as well. With nearly a month left on their Kickstarter page, they have nearly doubled their initial funding goal.

Check out the video presentation on their Kickstarter page to get a better look at the Revolights project.

[Thanks, medix]

Making Wheelchairs More Safe Through High Visibility

lights_and_sounds_wheelchair

When traveling around the city or even rural areas in a wheelchair, we imagine it can be pretty easy to get overlooked. [Rui] was asked to add some lights and sounds to an electric wheelchair in order to ensure that its rider remained visible to those around him.

The system uses several different components to ensure that the driver can be seen. The first is a message board strapped to the back of the chair which was constructed from a pre-made 8×32 LED matrix enclosed in an acrylic project box. The board uses a PIC16F88 to store and display messages, which are triggered by a control board mounted near the chair’s joystick. He also added headlights and taillights, using bright white and red LEDs, respectively. A 107dB horn was mounted on the chair to ensure that if the driver is not seen, he will certainly be heard.

Everything looks like it fits nicely, without hindering the operation or looks of the chair. Check out the video below to see his high-visibility system in action.

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Watch Out Segway, Here Comes Tilto

tilto_demo

While the Segway enjoyed a few years of fame before falling off the radar, [Marcelo Fornaso] is hoping his creation has quite a bit more staying power. Inspired by the Segway’s ability to balance itself, he started thinking about how the concept could be improved. He felt that one of the Segway’s shortcomings arose out of the fact that the base platform was rigid and required the user to lean back and forth outside the device’s frame in order to turn it. He thought that this made the riding experience uncomfortable as well as risked causing the rider to fall over.

His creation, the Tilto, aims to both improve on the turning ability of the Segway while eliminating the need for handlebars. Based on a tilting mountain board design he had been tossing around for a while, the Tilto uses accelerometers and gyros to keep its balance, much like the Segway. His goal was to keep the vehicle balanced while traveling forwards and backwards, but also allowing the device to tilt from side to side without tipping over. This design keeps the rider mostly upright, allowing the user to direct the vehicle by leaning much like you would on a bicycle.

As you can see in the video below, the Tilto works pretty well, even in its prototype form.

Finally, a people mover that lets us get our gangsta lean on!

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Black Hat 2009: Parking Meter Hacking

For day two of Black Hat, we sat in on on [Joe Grand], [Jacob Appelbaum], and [Chris Tarnovsky]’s study of the electronic parking meter industry. They decided to study parking meters because they are available everywhere, but rarely considered from a security perspective.

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