Discussing Pulse-Width Modulation

September 21, 2010 by Mike Szczys 53 Comments

[Michael Kleinigger] posted a lengthy discussion on Pulse-Width Modulation that goes beyond the traditional beginner tutorial. He starts a bit of background info on PWM and a tip about using a camera to judge frequency and duty cycle of LEDs. From there it’s down the rabbit hole with some testing of power-loss versus frequency.

When you change from frequencies of 50 Hz to 1 MHz how does the parasitic power loss from switching affect the overall efficiency of the circuit? It turns out there’s a rather large amount of loss at the highest level, around 1.5 mW. The greatest balance of low power loss and elimination of flicker seems to be right in the 300-500 Hz range.

Another Approach To Power Meter Data Harvesting

September 21, 2010 by Mike Szczys 17 Comments

[Dodgy] wrote in to talk about his power meter data harvesting programs. This uses the same hardware by CurrentCost as the hack we looked at over the weekend but [Dodgy’s] implementation is different. It’s separated into two parts, the first is a webserver written in C that harvests the data and makes it available at an address on the network, the second is written in Perl to format and upload data to Google PowerMeter.

The C program serves data on a configurable port, defaulting to 3090. All of the data can be accessed in one line of code by loading http://127.0.0.1:3090, or individually with subdirectories like /watts, /time, or /tempr. From there you can do what you want with the data. The second part of [Dodgy’s] suite is a Perl script that polls the C server and sends the data to your Google account.

One thing that interests us is his comment that you should be able to compile the server side C code for an embedded device. It would be a nice energy savings to be able to upload data regularly without a PC running constantly.

Hackerspace Competition: Looks Promising

September 21, 2010 by Jakob Griffith 18 Comments

This is what happens when [Mitch Altman] comes together with hackerspaces nationwide to have a contest. In short, 5 hackerspaces will “take on the machine” and come up with 5 original ideas for existing devices. There are a few more rules, but you can catch them in the video in the link above. There is hinting at a slot machine that mixes drinks, a bike that makes ice cream, and more. What do you guys think is in store?

This is also a great opportunity to mention the hackerspaces wiki, find a community (or start one!) near you today and maybe [Mitch] will call on your hackerspace next competition. For now, we’ll keep you up to date with each hackerspace’s project and progress.

[Thanks Deven]

Continue reading “Hackerspace Competition: Looks Promising” →

Machined Steadicam, Steadier Than The Rest

September 21, 2010 by Jakob Griffith 11 Comments

No, the picture above is not a store made steadicam. Rather, a CNC machined one by [Matt]. Interestingly, unlike most steadicams we’ve seen before the gimbal is not the main focus of the design though an aluminum machined gimbal would make us drool. The central idea is allowing for X and Y axis adjustment to get oddly weighted bulky camera’s exact center of gravity. [Matt’s] steadicam is also designed to handle more weight than commercial versions, and (if you already have a CNC) to be much cheaper. There’s no video, but from the skill of craftsmanship we can safely assume it’s as good and level as some of the best.

Something Wicked This Way Comes

September 21, 2010 by Caleb Kraft 5 Comments

Halloween is rapidly approaching. This is just a reminder to you all to send in your Halloween hacks now so that we can all see them and steal your ideas get inspiration for our own projects. We’ve seen fantastic stuff in the past from motorized pumpkins to costumes that are simply awe-inspiring. Take a few moments to dig through the Halloween hacks we’ve run in the past.

Of course we understand that some of you will be pushing up to the big day to complete your projects. Just remember to take good pictures and document it all well.

New Term For Art: Sculptural Robotics

September 21, 2010 by Jakob Griffith 10 Comments

[Dan Roe] has been working on Sculptural Robotics for quite some time, and most recently presented his newest creation: Solar Flowers 2010. Typically, Sculptural Robotics (coined by [Dan] himself) are stand alone, static art presentations made from electronic components and wire. [Dan] of course has taken it quite a bit further; giving all his sculptures life using solar panels, motors, engine circuits, and more. Making them zero emission, and beautiful at the same time. You can catch four videos after the jump of his moving sculptures. Not that we’re picking favorites, but the dragonfly is pretty amazing if we do say so ourselves.

Continue reading “New Term For Art: Sculptural Robotics” →

Homebrew Firmware Upgrade For VCI-100 Turntable Controller

September 20, 2010 by Mike Szczys 13 Comments

We love hacks that take quality products and make them better. This enhanced firmware for the VCI-100 is a great example of that. In a similar fashion as the Behringer hack, [DaveX] reverse engineer the firmware for the device and figured out a few ways to make it better. It improves the scratch controller and slider accuracy to use 9-bit accuracy from the ADC readings, which in the stock version were being shifted down to 7-bits. There’s also a few LED tricks they call Disco Mode. They’re selling a “chip” that you need to flash the firmware but from what we can see it’s simply an RS232 converter so you might be able to figure out how to work without that part. We’ve embedded a demo of firmware version 1.4 after the break.

Continue reading “Homebrew Firmware Upgrade For VCI-100 Turntable Controller” →