Introduction: Cosmic Jellyfish Lamp
My final project explores one of my favorite topics, space. I was inspired by a recent supermoon to design a lamp that simulated lunar phases. However, as time went on, my interest in the project began to wane and I decided to look to the galaxy as a source of inspiration.
This project then took on another level of abstraction: space is like a vast sea; what creatures could then live there? Does it emit light? Could this exist as a lamp?
Somehow I ended up designing a jellyfish lamp. I am captivated by their form, and also wanted to express their beautiful yet menacing nature. The lamp spins, but in future iterations, I will want to eliminate that feature: it's not as versatile as a non-rotating lamp! But it looks cool.
Step 1: Materials and Features
Rotation of the main body of the jellyfish:
controlled by a 12V Stepper Motor, which can be found many places, but I got mine from adafruit http://www.adafruit.com/products/918.
Blinking lights - 10mm, 5mm and 3mm diffused white LEDs.
(Motion-activated - PIR sensor as motion detector. http://www.adafruit.com/products/918
Two plastic hemispheres from Canal Plastics 20 inch diameter: http://canalplastic.com/
Clear acrylic for LED bed (home depot, canal plastics)
Threaded metal rod
Wire snipper and stripper
Step 2: Sketched Diagram
This diagram illustrates the connections between the various elements described.
12V Stepper Motor --> chrome plated threaded rod ---> laser cut acrylic ---> arduino breadboard/battery --> LEDs (rubber tubing encased)
Step 3: Light Blink Code
I ended up incorporating a code that made the LEDs blink at random. This was a rather elegant and simple looking code that eliminated the busywork that comes with using a code that includes delays. Including delays in the code would interfere with the movement of the motor.
Here is the code I cobbled together - it works!
Step 4: LED Treatment
Next step was to solder the wires to the LEDs. I cut the wires to various lengths, from short to long - to mimic jellyfish tentacles, which aren't all alike.
Step 5: Jellyfish Body
I used a 1/8 sheet of acrylic to make a platform that would contain the arduino board and battery pack, as well as provide a place to suspend the tentacles from and attach the threaded rod to.
I drew up a pattern of spiraling circles in Illustrator. See below:
I sent it to a laser cutter. This object will serve as an LED bed and help to consolidate the arduino and battery. It needs to be symmetrical because the faster the motor rotates the more wobbly the system will become. But it's unlikely to reach those speeds if you're reasonable about your stepper motor code!
Step 6: Tentacle Detail
I next encased the wire/LED combination in thin rubber tubing. The texture is a close approximation. (I think next time, I will experiment with less rigid rubber tubing.)
I also nestled hot glue between the LED positive and negative legs to keep within the organic theme. Using the typical black electrical tape would not look good with the rubber tubing!
NOTE: This also prevents short circuiting. The hot glue acts as an insulator. Be warned: hot glue is hot! Use caution with it. Using the typical black electrical tape would not look good with the rubber tubing!
Step 7: The PIR SENSOR
The PIR sensor calibrates to the temperature of environment, and then detects all subsequent changes in it, within a specific range, that is. This translates to motion-detection, technically, although by definition, this isn’t exactly what occurs. PIR sensor activation allows current to flow into the rest of the circuit. In the following sketch, LEDs light up upon PIR sensor activation. This is a step to test if your PIR sensor works.
I have modified a PIR sensor code to account for the number of LEDs (and therefore output pins):
Step 8: Rotation, Rotation
I decided to use a stepper motor to spin my jellyfish. Stepper motors, unlike servo motors, allow for smooth rotation by dividing a full turn into a number of equal steps.
Set up the circuit as shown.
Disclaimer: my motor didn't end up working with my code, so I cheated and purchased a disco-ball motor. The speed of the rotation suited my project, but I would have liked to experiment more with controlling a stepper motor. Next time, for sure.
Step 9: Putting It All Together
This is a super lo-fi project that was fun to make. I'm looking forward to building on it and taking it to the next level of completion.
Here is a video I made of it working: https://www.youtube.com/watch?v=DD9U3JU5MjQ