Electronic Bike Derailleur

June 6, 2012 by Brian Benchoff 38 Comments

[Nabil] sent in an awesome electronic bicycle derailleur. Now, instead of pulling a steel cable with a shifting mechanism, [Nabil] can change gears electronically. As a bonus, the derailleur can be controlled by a small bicycle computer, so he’s always in the right gear.

The new electronic derailleur is controlled by a pair of servos with push buttons in the handle bar. This allows [Nabil] to automatically trim his chain, completely eliminating chain rub.

This electronic shifter is part of [Nabil]’s much large bike computer project. In addition to electronic control of what gear the bike is in, [Nabil] will be adding a GPS, accelerometer, an altimeter and a heart rate monitor and pulse ox meter. That’s an impressive bit of kit, and we cant wait to see the entire project finished. You can pick up the current version of the design over on GitHub and follow all the updates on [Nabil]’s blog.

Bike Alert Tells Drivers To Back Off

June 4, 2012 by Mike Szczys 79 Comments

Bicycle commuters are often in a battle with drivers for space on the road. [Hammock Boy] does all of his commuting on two human-powered wheels, and is quite interested in not getting hit by a car. He decided to ply his hobby skills to build a device that helps keep him safe. It’s not just a tail light, it’s a sensor that shines brighter the closer a car is to the back of the bike.

The sensor portion is the ultrasonic range finder seen in the center of the protoboard. Surrounding it is a set of LEDs. Each is individually addressable with the whole package controlled by an Arduino. The sketch measures the distance between the back of the bike and whatever’s behind it. If there’s nothing, one Red led is illuminated. If there is an object, the lights shine brighter, and in different patterns as the distance decreases.

Certainly the next iteration could use a standalone chip without the need for the whole Arduino. This could even work with two battery cells and no voltage regulator. We also think the use of any other color than Red LEDs is suspect but we do love the concept.

LED Bicycle Hack Makes Sure You’re Seen At Night

May 31, 2012 by Mike Szczys 13 Comments

The bicycle tail and head lights that we’re accustomed to are small add-on modules. This take on the idea uses strips of LEDs to protect you from behind. They’re very bright, matching the pair of LED headlights that are attache to the handlebars.

Apparently [A.Davis12] had some LED strips laying around. There’s not what we’re used to seeing, but they have a similar footprint so you should be able to substitute the kind that come on a spool and may be cut to length. The majority of the build time was spent integrating the lights and their control wires with the frame of the bike. The frame already has holes in it for feeding the control wires for brakes and gear shifting inside the tubing. It sounds like it was a pain, but eventually he managed to get all of the routing done. Two red strips are zip-tied to the back of the seat stays. They are powered by a lithium battery inside the project box which mounts under the back of the saddle. A flip switch on the case lets you turn them on without stopping.

[Thanks Arpad]

The Bicycle Can Tell Us How To Make It Better

May 28, 2012 by Mike Szczys 16 Comments

Over the years bicycle design has changed. Materials were upgraded as technology advanced, and accumulated knowledge helped bicycle builders make improvements along the way. But deep analysis with the intent to make meaningful improvements has not been widely embraced. Reasearchers at UC Davis are looking to expand into this frontier by letting the bicycle tell us how it can be improved. This is one of the test bikes they’ve been working on, which is mainly aimed at data harvesting. They’re hoping to find some real improvements based mostly on how the machine can get out of the rider’s way as much as possible. The thought here is that the rider’s body makes up 80-90% of the volume of the vehicle and should be accommodated in every way possible.

Sure, this could be a case of trying to build a better mouse trap. But listening to the discussion in the video after the break really drives home the complex issues of stability and locomotion that go into these seemingly simple vehicles. We’re going to guess the final recommendations will not involve making the bike five times taller.

Continue reading “The Bicycle Can Tell Us How To Make It Better” →

Amphi-Cycle Lets You Ride The Trails, The Waves, And Back Again

May 14, 2012 by Mike Nathan 24 Comments

amphi-cycle

Hackaday regular [Berto] is always looking for new ways to get around, and wrote in to share his most recent creation, an amphibious bicycle.

He bought an off-the-shelf inflatable boat and constructed a rig that allows him to stably mount the bike on it. Once [Berto] comes across a body of water he wants to cross, all he requires is about 7 minutes time to inflate the boat and attach his bike. Using a modified version of his electric drill-based trolling motor we saw last year, the Amphi-cycle glides across the water effortlessly as demonstrated by his assistant in the video below.

Right now the boat is propelled solely by the trolling motor and a large lead-acid battery. We would love to see the amphi-cycle powered by its rider, though we don’t know how that would affect the “one boat fits all” design [Berto] is aiming for.

Continue reading “Amphi-Cycle Lets You Ride The Trails, The Waves, And Back Again” →

Rail Bike Conversion Is A Success, And A Failure

May 1, 2012 by Caleb Kraft 40 Comments

There is a long tradition of hacking transportation to work on the rails. People have done it to all kinds of things for many reasons. Some are for rail maintenance, others are simply to enjoy the tracks. With as much unused railways as we have, it seems a shame to waste them. This hack turns a bicycle into into a rail bike with the use of some conduit, a cut up razor scooter, and a fork from another bike. After some tinkering with spacing to make the whole thing a little smoother on the rails, the whole thing seemed like a success. That is, until the front rail guide caught a railway tie and the rider was tossed. Not only that, the impact destroyed his bike frame.

So, does this wreck mark this as a failure? Or is this simply another step in the iterative process we all tend to use. The only difference is if he carries on to build another.

Home Brew Motorized Bicycle Is A Super Grocery Getter

April 28, 2012 by Brian Benchoff 14 Comments

[Thor] sent in an awesome motorized bike build he found coming from the fruitful workshop of [Jim Gallant]. It’s an incredible piece of work built nearly entirely from scratch.

[Jim] welded the frame together on a home-built jig that keeps all the chrome-moly tubes in alignment before they’re pieced together. With the jig, the frame was kept extremely straight making a bike that turns very well and can be ridden no-handed.

All of [Jim]’s previous motorized bikes used small Honda engines, but after hearing Robin Subaru engines are more reliable he decided to give one a go. The motor is attached to the derailleur gears with a continuously variable transmission usually found in scooters. [Jim]’s earlier motorized bikes didn’t have indexed shifting and disc brakes like modern motorized bikes, but he decided to throw them in anyway. Everyone who rides his new super grocery getter comments on how smooth the ride is with these additions.

While [Jim] doesn’t have an official speed or MPG rating, he’s guessing this bike can carry three bags of groceries at 30 mph at 170 miles per gallon. A very efficient mode of transportation that is much safer than the other motorized bikes we’ve seen before.