Snakes in a tree
Phil Pilgrim (PhiPi)
Posts: 23,514
After my LED special effects were done with A Midsummer Night's Dream at the local high school, I brought the equipment home with the idea that I would deploy it for the holidays in a tree next to the street. Here's a video that shows one of the effects that I programmed using the same Activity Board WX used at the HS:
https://vimeo.com/manage/videos/783152129
Since the video is rather dark, here's a still photo of the tree with the same effect running:
Here is a picture of the main controller:
The keypad is used to select the desired effect and is mounted atop a Parallax Activity Board WX, with an XBee Pro for receiving remote commands. This unit was placed backstage for the play and was a backup in case the remote unit malfunctioned.
Here's a photo of the remote:
This was placed in the lighting control booth for the HS play. It includes an XBee transceiver for sending commands to the control unit. I'm tempted to lend this unit to my neighbors across the street so that they can select from multiple tree effects on their own.
-Phil
Comments
Great job, Phil. The chasing LEDs in the tree look awesome. How far away can the remote be in controlling your tree display?
The XBees are the Pro model, which advertises a range of one mile under ideal line-of-sight conditions. So I don't think across-the-street should be a problem -- even indoors-to-indoors. We shall see ...
-Phil
Is that a back lighted keypad?
@Phil: Are you transmitting commands that control built-in sequences and timing, or raw pixel data (kind of like DMX)?
Yes: This one.
It had to be back-lighted, since it was used in dark environments (i.e. backstage and lighting control booth). It's kind of expensive, but mission-critical to the drama production, so I didn't want to risk failure.
The sequences are programmed into the main control unit. The keys on both units select which sequence to run. The sequences are controlled by a master fader, since the play director told me that every sequence had to start with a fade-up and end with a fade-down. The actual sequences are performed in a separate cog that receives commands and master-fade info from its parent.
The main control unit sends the LED sequences generated by your WS2811 driver via RS485. At the other end of a long cable is a small 485-to-5V-logic converter that drives the LED string. I had to use an RS485 transceiver that wasn't slew-rate limited, due to the high speed of the LED driver output.
-Phil