Post by jhornbr225 on Sept 29, 2019 14:02:28 GMT -5
We'll be attending two Halloween parties this season, and we hand out candy at the sister-in-laws house. My wife wants to be a Jawa. So her and her Mom are taking care of the robe, the bandoleer, etc. I told her I would take care of the glowing eyes.
She had though she would just use parts of a small flashlight, as there are multiple tutorials on the web. I looked at a few, and it seemed to me that they put a lot of effort into getting the color right with just the right material, or something to stain the material (one used mustard to get the yellowish tint). i figured that I would just use RGB Leds, and an Arduino with PWM to make the color and the brightness correct. I see that an Adafruit Trinket is tiny, and has 3 PWM outputs available. And I had a couple, Perfect. So I ordered a string of 1 Meter of RGB waterproof LED's from Ebay for $1. These are 12V, 5050 size, (5mm x 5mm), and you can cut them into sections with an increment of 3 LEDS. I found they are 12V because the three LED's are in series. The red color has a 300 Ohm resistor in series, as the Red LED's forward voltage is 2V. The Green and Blue have a 130 Ohm resistor each, as their forward voltage is 3 volts. I cut 3 LEDS off the meter long strip, and was able to peel back the clear waterproof cover. I was then able to desolder the 3 LED's. Just putting my meter across them in Diode check causes them to light up. The red is brighter, due to is lower voltage drop. I soldered some very thin wire strands on them, dead bug style, as they are surface mount, for further testing. Today I plan to try running them on 5V. Instead of 3 LED's in series, I'll use 2, so that hopefully I can use 5V. I'll have no problem with the Red, as those only take 2V. The Blue and the Green have me a little worried though. Technically at 5V instead of 6V, they won't be able to get full brightness, but I have a feeling that I'm really going to be cranking the PWM duty cycle down, as these things looked really bright at 12V, with 20mA going through each color. I also doubt that I'll need any Blue at all, as a Jawa's eyes are pretty much yellow. I will hook up the Blue though, just in case. I figure putting an array of these with 3 rows of the top and bottom row being 3 LED's and the middle row being 4, 10 total, it will give the appearance of roundess. And I think with 10 LED's for each eye, my problem will be that they will be too bright.
I'm going as Luke Skywalker. Although it would have been more appropriate to be Tatooine Luke, I'm going for Jabba's Palace Luke, which technically is Tatooine. I feel the black will be easier. I tried to talk her into taking a lightsaber, and attaching it to her chest, and then having the blade come out her back, but she didn't think that was funny. Her and her Mom are going to make a backpack though, and she's going to carry my remote control BB-8 in it. It's the big one, about 19" tall, and I think I can turn on just the head and have it make BB-8 noises. She just has to practice her "Hootini !".
She had though she would just use parts of a small flashlight, as there are multiple tutorials on the web. I looked at a few, and it seemed to me that they put a lot of effort into getting the color right with just the right material, or something to stain the material (one used mustard to get the yellowish tint). i figured that I would just use RGB Leds, and an Arduino with PWM to make the color and the brightness correct. I see that an Adafruit Trinket is tiny, and has 3 PWM outputs available. And I had a couple, Perfect. So I ordered a string of 1 Meter of RGB waterproof LED's from Ebay for $1. These are 12V, 5050 size, (5mm x 5mm), and you can cut them into sections with an increment of 3 LEDS. I found they are 12V because the three LED's are in series. The red color has a 300 Ohm resistor in series, as the Red LED's forward voltage is 2V. The Green and Blue have a 130 Ohm resistor each, as their forward voltage is 3 volts. I cut 3 LEDS off the meter long strip, and was able to peel back the clear waterproof cover. I was then able to desolder the 3 LED's. Just putting my meter across them in Diode check causes them to light up. The red is brighter, due to is lower voltage drop. I soldered some very thin wire strands on them, dead bug style, as they are surface mount, for further testing. Today I plan to try running them on 5V. Instead of 3 LED's in series, I'll use 2, so that hopefully I can use 5V. I'll have no problem with the Red, as those only take 2V. The Blue and the Green have me a little worried though. Technically at 5V instead of 6V, they won't be able to get full brightness, but I have a feeling that I'm really going to be cranking the PWM duty cycle down, as these things looked really bright at 12V, with 20mA going through each color. I also doubt that I'll need any Blue at all, as a Jawa's eyes are pretty much yellow. I will hook up the Blue though, just in case. I figure putting an array of these with 3 rows of the top and bottom row being 3 LED's and the middle row being 4, 10 total, it will give the appearance of roundess. And I think with 10 LED's for each eye, my problem will be that they will be too bright.
I'm going as Luke Skywalker. Although it would have been more appropriate to be Tatooine Luke, I'm going for Jabba's Palace Luke, which technically is Tatooine. I feel the black will be easier. I tried to talk her into taking a lightsaber, and attaching it to her chest, and then having the blade come out her back, but she didn't think that was funny. Her and her Mom are going to make a backpack though, and she's going to carry my remote control BB-8 in it. It's the big one, about 19" tall, and I think I can turn on just the head and have it make BB-8 noises. She just has to practice her "Hootini !".