Motion sensor to CV conversion?

[pugix]

I am thinking about a sound installation where people would be wandering in and out, and wondering if I could have motion detectors sensing their presence/movement and generating CV to control the synthesizer.

Does anyone know of a battery-powered motion sensor that could be tapped to produce some CV? It should have adjustable range/sensitivity.

Maybe I could modify a portable alarm or light and have it put out a control instead of an alarm. The light might even provide feedback to the people triggering it.

Here's a light:

http://www.walmart.com/ip/Mr.-Beams-Sec ... t/16664171

Problem is that it only works in dark ambient light.

Here's a wireless doorbell motion sensor.

http://www.smarthome.com/30611/Honeywel ... 02N/p.aspx

I could modify the chime (also battery powered) to get a CV out.

Thoughts?

[beeedy]

I feel that the best you could do with the wireless doorbell or light is output a gate/trigger signal. Both of those little guys will most likely have some sort of microcontroller in them reading the sensor values and flipping a relay. So sadly, no analog!

It may be worth looking into an Arduino and some sensors. The Arduino has many very cheap and easy to use sensors that seem they work just fine for your project! One particular sensor that comes to mind is a ultrasonic range finder. Can be used to measure distances with ultrasound, but with some simple code it could also be used to detect motion.

All you would need then is a DAC to convert the digital signal from the Arduino into a CV for your synth. There are many topics on this forum and across the web on how todo such this.

3$ ultrasonic range finder: http://dx.com/p/hc-sr04-ultrasonic-sens ... ule-133696

[Revok]

This is a great concept.

Here is a pretty detailed description of the PIR sensors:

http://www.ladyada.net/learn/sensors/pir.html

It would be cool to wire a bunch of these to the HL Midi CPU and have a complex motion controller. Midi-cv would be needed so there probably are simpler ways.

Maybe experimenting with some photo-resistors could be a crude but simple approach.

[Revok]

Using something like this for the sensors would kill it:
http://www.parallax.com/tabid/768/produ ... fault.aspx

[Revok]

Sorry if I'm spamming here but I got way too into this one. In addition to motion, you could place various mics throughout the space and use this circuit:
http://www.circuitstoday.com/frequency- ... -converter

It could be cool to put the mics near on on the floor so footsteps would send control the voltage.

[pugix]

Revok, thanks for the spam! 8_)

Looks like I will have to put on my experiment's hat and try out some of these circuit ideas. I'll spend more time researching tomorrow.

[don h]

You might look at microwave sensors too, here's one:
http://www.openimpulse.com/blog/product ... or-module/

[CJ Miller]

I don't know if they're suitable for this installation in particular, but the Sharp analog optical sensors are quite easy to use. They are powered by and output analog voltage, so at most a CV processor module might be needed to bring the output to a usable range. There are a few kinds, which cover differing range of proximity. I have experimented a bit with the close ones for hand jive.

http://www.pololu.com/catalog/product/1137

edit: FYI they use "JST" connects. I hadn't seen these before, which was a small hitch for me. It's a cable header type which is fairly common with Japanese stuff.

[oozitron]

An idea: Since some of these sensors (I've been playing with a Sharp distance sensor a bit) will sometimes produce an outout voltage that jumps around, running them through a slew (glide/portamento) will remove those drastic jumps.

And once you've got them smoothed out, run them into a CGS Slope Detector. This can be used to fire off events (advance sequencers, gate envelopes, etc) when the voltage changes. Very cool :-)

Drew

[Jarno]

+1 on combining sensors, you might also use strain gauges in the floorboards, or walls. Maybe add pir for simple on/off triggering. And ultrasonic rangesensors, hook it all up to an arduino. Or get one of the doepfer diy interfaces to midi, thats even simpler. not sure how to hook the ultrasonic sensors up to this.

[spunkytoofers]

take a peak at nerdy robot webstores. just google search. alot of them make pre-fab sensors that will output 0-5v without programming a microprocessor. maybe a little pricier but worth it for me because i just can't get into coding quite yet. works great. i used a vex robotics accelormeter for a different but similiar project

[pugix]

I like the idea of a sensor that puts out voltage. I can build analog circuitry around that and not have to get into a whole arduino thing, which I simply have no time for.

[wmonk]

In Gent lives Belgian artist Godfried-Willem Raes, who built quite a lot of automated instruments. In his performances he also uses sensors to trigger these automated instruments.
His website is full of information on how he built the instruments and the sensors. It might be interesting.
Although a little warning, it can be a bit weird sometimes

http://logosfoundation.org/index-god.html

[raisinbag]

How close could you put the sensors the people? The theremin from PAIA might work? You could probably even run the wands a little bit away from the unit? You would have cv and gates already "ready" for the modular world.

[instruments of things]

Hi,

maybe a little bit late, but we just released a wireless Eurorack sensor interface module "2.4SINK". It's currently available on Kickstarter:





The module offers 16 x 12 bit multimode outputs.
Furthermore we have created a custom firmware for Movesense sensors including 9 degrees of freedom sensor fusion for high precision motion control and low latency applications.
More information can be found here.

[pugix]

Hi,

maybe a little bit late, but we just released a wireless Eurorack sensor interface module "2.4SINK". It's currently available on Kickstarter:





The module offers 16 x 12 bit multimode outputs.
Furthermore we have created a custom firmware for Movesense sensors including 9 degrees of freedom sensor fusion for high precision motion control and low latency applications.
More information can be found here.

This looks perfect for projects I've been doing with dance. I built a DIY wireless muscle sensor, but the motion sensor idea is more flexible (if more costly). I'll be spreading the word about the Kickstarter.

[dubonaire]

Hi,

maybe a little bit late, but we just released a wireless Eurorack sensor interface module "2.4SINK". It's currently available on Kickstarter:

...

The module offers 16 x 12 bit multimode outputs.
Furthermore we have created a custom firmware for Movesense sensors including 9 degrees of freedom sensor fusion for high precision motion control and low latency applications.
More information can be found here.

This looks perfect for projects I've been doing with dance. I built a DIY wireless muscle sensor, but the motion sensor idea is more flexible (if more costly). I'll be spreading the word about the Kickstarter.

This must be a record for an OP replying to a 6.5 year necropost!

It looks great!

[av500]

viewtopic.php?t=160915

[Pachicito]

Little Bits by Korg!

Motion Sensor
https://sphero.com/collections/all/prod ... on-trigger

MIDI I/O
https://sphero.com/collections/all/products/midi

CV I/O
https://sphero.com/collections/all/prod ... ol-voltage