Skateboards are fun, but you have to do all that pesky kicking in order to get anywhere. That’s why [Nick] decided to build his own electric skateboard. Not only is the skateboard powered with an electric motor, but the whole thing can be controlled from a smart phone.
[Nick] started out with a long board deck that he had made years ago. After cleaning it up and re-finishing it, the board was ready for some wheels. [Nick] used a kit he found online that came with the trucks, wheels, and a belt. The trucks have a motor mount welded in place already. [Nick] used a Turnigy SK3 192KV electric motor to drive the wheels. He also used a Turnigy electronic speed controller to make sure he could vary the speed of the board while riding.
Next [Nick] needed some interface between a smart phone and the motor controller. He chose to use an Arduino Nano hooked up to a Bluetooth module. The Nano was able to directly drive the motor controller, and the Bluetooth module made it easy to sync up to a mobile phone. The Android app was written using MIT’s App Inventor software. It allows for basic control over the motor speed so you can cruise in style. Check out the video below for a slide show and some demonstration clips.
It’s a popular project, and eerily similar to the one we saw a couple months back.
Continue reading “On Your Phone While Driving an Electric Skateboard”
Biohackers, fire up your laser cutters. [CopabX] has developed OpenFuge: a (relatively) low-cost, open-source centrifuge from powerful hobby electronic components. If you thought the VCR centrifuge wasn’t impressive, trolls be damned— OpenFuge can crank out 9000 RPM and claims it’s capable of an impressive 6000 G’s. [CopabX] also worked in adjustable speed and power, setting time durations, and an LCD to display live RPM and countdown stats.
And it’s portable. Four 18650 lithium cells plug into the back, making this centrifuge a truly unique little build. The muscle comes from a DC outrunner brushless motor similar to the ones that can blast you around on a skateboard but with one key difference; an emphasis on RPMs over torque. We’re not sure exactly which motor is pictured, but one suggestion on the bill of materials boasts a 6000 KV rating, and despite inevitable losses, that’s blazing fast at nearly 15V.
You’ll want to see the demonstration video after the break, but also make time to swing by Thingiverse for schematics and recommended parts.
Continue reading “OpenFuge: an open-source centrifuge”
It’s been a long time coming, but efforts to create Open Source brushless motor controller are finally paying off.
The Open-BLDC project aims to create an open source motor controller for the brushless motors usually found in remote control airplanes, helicopters, and quadcopters. Normally, these motor controllers – usually called electronic speed controllers – can’t supply more than a few dozen amps, and are usually only controllable via a servo signal.
The Open-BLDC goes far beyond the capabilities of off-the-shelf ESCs with up to 200 amps of output, TTL level serial input, and the ability to use regenerative breaking.
While the Open-BLDC project is far from complete, the team working on the hardware hopes to add I2C, CAN, and PPM interfaces, along with speed and torque control.
There is no word on when, or even if, the Open-BLDC will ever be available for sale, but with the features it has it would be welcomed by just about any builder constructing a gigantic RC vehicle.
You can salvage some nice motors out of optical drives but they can be tricky to control. That’s because brushless DC motors require carefully timed signals used in a process called Electronic Speed Control (ESC). [Fileark] built and ESC using an Arduino and has a couple of posts explaining the concept and demonstrating how it works. His test circuit uses six 2N2222 transistors to protect the Arduino from excessive current. You can see six red LEDs above which are inline with the base of teach transistor. This gives visual feedback when a transistor is switched, a big help for troubleshooting your circuit.
Once you’ve seen the videos after the break you’ll probably come to the conclusion that this is an impractical way to use a brushless motor. But it is a wonderful way to learn about, and experiment with the concept of ESC. Chances are you can get your hands on an old optical drive for free, making this an inexpensive weekend project.
Continue reading “Arduino Electronic Speed Control explained”
Ah, the heady aroma of damp engineers! It’s raining in Silicon Valley, where the 2010 Embedded Systems Conference is getting off the ground at San Jose’s McEnery Convention Center.
ESC is primarily an industry event. In the past there’s been some lighter fare such as Parallax, Inc. representing the hobbyist market and giant robot giraffes walking the expo. With the economy now turned sour, the show floor lately is just a bit smaller and the focus more businesslike. Still, nestled between components intended to sell by the millions and oscilloscopes costing more than some cars, one can still find a few nifty technology products well within the budget of most Hack a Day readers, along with a few good classic hacks and tech demos…
Continue reading “Report from ESC Silicon Valley 2010″