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How to build a Smart Lightbulb in a Weekend

blog.kytelabs.com

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Re: How to build a Smart Lightbulb in a Weekend

#11

Post by nitrogen »

jgonzalez wrote: post #10
nitrogen wrote: post #4

This is a very cool project. How does it do on lumens per watt?

We're not sure how to calculate it but we did some crappy math and it got us around 6.2 lumens per watt. Again, we're not sure if this is correct. You can use the following datasheet if you'd like to calculate it yourself. http://www.adafruit.com/datasheets/FLR-100WAS-RGB.pdf Overall, it's decently bright but not as bright as a normal light bulb.

If you're running them at full power, I calculated 9.9lm/W by adding the typical mcd values (3700mcd), plugging them and the 50deg beam angle into [0] to get 2.178 lumens, then dividing by the summed power rating (220mW). Of course, this is ignoring the power used by the bluetooth module, Arduino, and waste heat in the power supply.

For comparison, an incandescent bulb is 15lm/W, while the Hue bulbs are 70.6lm/W. So it's no Hue replacement, but still a cool, fun project.

[0] http://led.linear1.org/lumen.wiz

Re: How to build a Smart Lightbulb in a Weekend

#12

Post by jgonzalez »

nitrogen wrote: post #11
jgonzalez wrote: post #10

Earlier quoted context omitted.

We're not sure how to calculate it but we did some crappy math and it got us around 6.2 lumens per watt. Again, we're not sure if this is correct. You can use the following datasheet if you'd like to calculate it yourself. http://www.adafruit.com/datasheets/FLR-100WAS-RGB.pdf Overall, it's decently bright but not as bright as a normal light bulb.

If you're running them at full power, I calculated 9.9lm/W by adding the typical mcd values (3700mcd), plugging them and the 50deg beam angle into [0] to get 2.178 lumens, then dividing by the summed power rating (220mW). Of course, this is ignoring the power used by the bluetooth module, Arduino, and waste heat in the power supply. For comparison, an incandescent bulb is 15lm/W, while the Hue bulbs are 70.6lm/W. So…

Thanks for the explanation :).

Re: How to build a Smart Lightbulb in a Weekend

#13

Post by rgonzalez »

nitrogen wrote: post #11
jgonzalez wrote: post #10

Earlier quoted context omitted.

We're not sure how to calculate it but we did some crappy math and it got us around 6.2 lumens per watt. Again, we're not sure if this is correct. You can use the following datasheet if you'd like to calculate it yourself. http://www.adafruit.com/datasheets/FLR-100WAS-RGB.pdf Overall, it's decently bright but not as bright as a normal light bulb.

If you're running them at full power, I calculated 9.9lm/W by adding the typical mcd values (3700mcd), plugging them and the 50deg beam angle into [0] to get 2.178 lumens, then dividing by the summed power rating (220mW). Of course, this is ignoring the power used by the bluetooth module, Arduino, and waste heat in the power supply. For comparison, an incandescent bulb is 15lm/W, while the Hue bulbs are 70.6lm/W. So…

Thanks for the thorough calculations, it'll definitely help us moving forward. Also, glad you mentioned Hue bulbs, we were focusing on Bluetooth as our main differentiation factor but we have to cover the basic as well i.e. good lighting.

Re: How to build a Smart Lightbulb in a Weekend

#14

Post by BHSPitMonkey »

hmottestad wrote: post #3

It's very pretty they put everything into the shell of the bulb. My smart bulb is a regular led lamp that I've run the power through a nice transistor and arduino sitting next to the lamp on my desk. However I have a nice webapp and even a brightness sensor to adapt to light in the room. Some videos of my lamp: http://fluffyelephant.com/2012/09/two-videos-about-my-led-la... And a write-up: http://fluffyelephant.com/2…

In case the videos aren't working for other people, too, here are the direct YouTube links:

* http://www.youtube.com/watch?v=xHFkA9gsG0Y

* http://www.youtube.com/watch?v=_glWFDGBJq0

Re: How to build a Smart Lightbulb in a Weekend

#15

Post by hmottestad »

BHSPitMonkey wrote: post #14
hmottestad wrote: post #3

It's very pretty they put everything into the shell of the bulb. My smart bulb is a regular led lamp that I've run the power through a nice transistor and arduino sitting next to the lamp on my desk. However I have a nice webapp and even a brightness sensor to adapt to light in the room. Some videos of my lamp: http://fluffyelephant.com/2012/09/two-videos-about-my-led-la... And a write-up: http://fluffyelephant.com/2…

In case the videos aren't working for other people, too, here are the direct YouTube links: * http://www.youtube.com/watch?v=xHFkA9gsG0Y * http://www.youtube.com/watch?v=_glWFDGBJq0

Thanks for posting this. I'm the author and I would be very grateful if you could give me a bit more details about what wasn't working about the videos so I can fix the problem.

Re: How to build a Smart Lightbulb in a Weekend

#16

Post by BHSPitMonkey »

hmottestad wrote: post #15
BHSPitMonkey wrote: post #14

Earlier quoted context omitted.

In case the videos aren't working for other people, too, here are the direct YouTube links: * http://www.youtube.com/watch?v=xHFkA9gsG0Y * http://www.youtube.com/watch?v=_glWFDGBJq0

Thanks for posting this. I'm the author and I would be very grateful if you could give me a bit more details about what wasn't working about the videos so I can fix the problem.

When I visited your links, the plugin you use for embedding the videos was failing, replacing the videos with an error message. I peeked at the page source and found the YouTube video IDs there. It seems to be working now.

Re: How to build a Smart Lightbulb in a Weekend

#17

Post by hmottestad »

BHSPitMonkey wrote: post #16
hmottestad wrote: post #15

Earlier quoted context omitted.

Thanks for posting this. I'm the author and I would be very grateful if you could give me a bit more details about what wasn't working about the videos so I can fix the problem.

When I visited your links, the plugin you use for embedding the videos was failing, replacing the videos with an error message. I peeked at the page source and found the YouTube video IDs there. It seems to be working now.

Thanks.
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