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Maj. Tom and Ground Control

Maj. Tom and Ground Control

   A David Bowie themed party this evening.  I put on a military helmet, gave myself the rank of major and went by Tom.  Xiphos put on a hat with "Ground Control" on it.  I don't know much about David Bowie, but I figured most people would get that reference.
   Some days things just don't work out.  I picked up some items to fix things around the house, but nothing worked out.  First there was a shutoff valve I grabbed for the air compressor.  Everything for pneumatics is the same size—everything but the shutoff valve I picked up.  I also grabbed some new hose for the furnace.  We have a whole-house humidifier.  A few days ago it was leaking water all over the place and I had to shut it off.  I wasn't aware how well this device worked until then as every morning since I've had a blood nose.  It was a leaky drain hose that was causing the problems so I picked a new one up.  And wouldn't you know it, I grabbed one size too small.  Lastly I decided to wire up my DMX cables.  But I couldn't get the 5-pin to 3-pin adapter to work.  Xiphos has an other one, but he wasn't available to assist.  So I was unable to test the one cable I assembled.  I want to test that before I assemble the 9 remaining cables.  Something about how much luck I've had throughout the day told me I should play it safe.  So not a lot accomplished.
   Pictured is the basement theme for the Speakeasy party.  Should any stoolies show up, we had a station for Knuckles to deal with them.
RGB laser

RGB laser

   My RGB laser has a combine power of 500 mW.  This is the end of the class 3B laser devices but still safe to view the reflection of the beam on a matte surface.  You cannot really get safety glasses for RGB lasers because such devices would block all visible light.  So when setting up the laser I would only enable a single channel.  I have safety glasses for red, and green/blue lasers.  The green/blue safety glasses are new, and when you put them all, blue and green disappear.  It's kind of crazy, but what was a perfectly visible trance just vanishes.  They do a pretty good job.
   The power of this laser device is fairly evident in this picture.  There is a little fog in the air to help visibility, but all the lights are on and the beam is still very prominent.  It is a cool little device.

February 14, 2016

RGB Laser Tunnel Effect

New Laser Tunnel

New Laser Tunnel

My RGB laser arrived yesterday, and today I got to play with it. There is no such thing as a true white laser because the nature of laser light is centered on a single wave length of light. However, using three lasers and beam combiners can produce a beam that visually appears white. This laser module has a 200 mW red, 100 mW green, and 200 mW blue laser diode with two beam combiners. The result is a 500 mW white beam.

My experiments with making a laser tunnel went well, but one item I failed to accomplish was a tunnel with counter rotating fingers. I tried using a PWM to dim the laser for some fingers, and keeping one at full brightness. But the laser can module can only transition no faster than 20,000 times/second which for this project isn't fast enough. However, having separate lasers to control, I can accomplish this effect. Rather than dimming a single laser, I can simply turn one or more of them off.

The changes to the code were minor. I simply duplicated the logic for the timer compare A interrupt and setup a second set of variables for timer compare B interrupt. This allows timer compare B to mimic what compare A does, but with different parameters. Didn't take long before I had the effect I was looking for.

   Metal shovels.  One's first thought is that they should hold up better than plastic.  However, once the paint chips off from being dragged over concrete, rust begins to attack the edge.  This is exacerbated by sidewalk salt.  Our shovel is only two years old, but the edge already has gaps due to rust.
   Our living room is light from a several strings of RGB LEDs.  We had a cheap controller to run them that started exhibiting some strange symptoms.  When the LEDs were at full strength, they would strobe.  I ordered a cheap replacement controller and put it in.  It is smaller and has more light modes.  Oddly, the RGB strip has color problems.  When set to white (all LEDs on at full strength) the light is different colors from different areas of the strip.  Not sure if it is a connection issue, or an artifact of manufacturing.  Regardless, it does provide a nice indirect light source.