I am considering a magic crystal ball project. Ideally, I’d like it to respond to the user’s (fortune teller’s) input and gestures with the circuit hidden within the base.

It definitely needs concealed within the base which will hold a crystal sphere such as quartz or preferably fluorite.

I estimate a not entirely opaque, but not entirely translucent, crystal ball should allow hidden LED lighting to play across the inner occlusions in a satisfactorily creepy manner.

What’s the community opinion on using a hidden mmWave proximity sensor to identify certain hand gestures, and repeated hand gestures, along with a microphone to physically and/or audibly trigger preprogrammed lighting, sound, and possibly vibratory effects?

Slow fade on to half light, gentle pulsating light, other colors…

I’m also interested in community suggestions for other types of sensors and effects I could include as well to increase the control or creepfactor? lol

 

The ball could talk Blue tooth or WiFi to a phone where a human makes the "creepfactor".

 

Historically, a theremin uses capacitance effects in order to respond to hand gestures.
You can also experiment with infra-red proximity sensors or even a small camera. Check out the imagining sensor in an optical mouse.

 

Check out the imagining sensor in an optical mouse.

That should be able to invent some useful effects !

 

Hello, that sounds like an interesting project. I think hand gestures are best processed through machine vision, so I'd install an external (hidden) camera going to a microcontroller/microcomputer equipped with a module that can send wireless signals to the crystal ball (with the advantage that the crystal ball won't need to consume that much power doing intensive computations and can instead reallocate its battery to fancy display/lighting)

 

Long ago assisted my girlfriend’s daughter with an art project that is somewhat similar to this project. She had a coffin shaped box with a translucent plastic sheet for the cover. Underneath it were printed quotes from notes she had received from past boyfriends. there was back lighting. Each quote could only be seen by activating one of four lights.

She tasked me with electronics that would light the lights individually based in where the viewer was standing. It had to appear almost random and be difficult to figure out how to light the lights.

I came up with the simplest scheme I could think of: there were four photocells placed widely apart on the top. Each was activated when the sensor was in shadow. These fed an and gate for each light, such that the light would come on only if some combination of the sensors was blocked. DIP switches selected which sensors were needed for each light.

It worked beautifully. The curiosity and voyeurism if the viewers led them to spend a long time trying to see all of the text, which was exactly what she wanted.

The point of this story is that a few photo sensors around the base nay be all you need to get some interesting effects based on where the shadow of the waving hands falls.

 

The ADPS-9960 is a proximity, ambient light, RGB, and gesture sensor that can be found as a module quite cheaply.

I don't know how it would perform through a crystal sphere, but it might be fine since "accuracy" is a relative thing and exactly where it senses wouldn't be an issue in your application.

Since it can do RGB sensing, colored light could affect the operation. For example in the presence of red (ambient) lighting, the ball could go green, &c.

 

Ah the trouble with external modules is in something I should have probably mentioned in the original post: this crystal ball is going to be mounted on the end of a wizards staff.

i really like the idea of a theremin, even as a sensor, and instead of converting to sound effects, using variable light effects instead?

 

The ADPS-9960 is a proximity, ambient light, RGB, and gesture sensor that can be found as a module quite cheaply.

I don't know how it would perform through a crystal sphere, but it might be fine since "accuracy" is a relative thing and exactly where it senses wouldn't be an issue in your application.

Since it can do RGB sensing, colored light could affect the operation. For example in the presence of red (ambient) lighting, the ball could go green, &c.

I would love experimenting with this. Thank you!

 

OK, a small video camera looking into the ball, and a small FM transmitter sending out the video signal to a receiver feeding a processor doing pattern analysis. More details when I am not so tired.

 

since base will be used to illuminate ball by color LEDs, one need to ensure no interference to the sensing element. or maybe move sensing into different spectrum. Melaxis makes IR camera modules like MLX90640ESF-BAB-000-TU.

 

OK, inside a ball at the end of a waizards staff still works for a SMALL video camera and a wireless link, and then a wireless link BACK to control the LEDs Maybe including a single character alpha dis[lay??Then it could have a whole PC running all sorts of code.