Need help for body presence sensing circuitry design

G

GT-Janos

New Member

• Oct 20, 2012

• #1

I need an inexpensive solution to detecting human presence (not motion) detection at a max. 5m (16ft) distance from the sensor preferably non-temperature based.

If the distance between the body and the sensor could also be approximated, it would be a bonus!

Am I expecting too much?

GT-Janos

 

alec_t

Well-Known Member

Most Helpful Member

• Oct 20, 2012

• #2

preferably non-temperature based.

Click to expand...

Why? Are you looking for corpses? If not, I think an IR sensor would be the best bet (but I don't see how that alone could indicate distance).

 

throbscottle

Well-Known Member

• Oct 20, 2012

• #3

Something using the same principle as a theramin? May be able to give you some idea of distance too.

 

Last edited: Oct 20, 2012

G

GT-Janos

New Member

• Oct 20, 2012

• #4

Hi Alec_t,

The gadget would turn on-off a heater and I thought that there could be some interference, but probably wouldn't.
I keep the corpses in the closet (without heating).

I'm new to the community, so how does it work work with your "experimental" circuitry? Cheers

 

G

GT-Janos

New Member

• Oct 20, 2012

• #5

Hi,

Thanks for your reply. I'll look up what theramin is.

Cheers

 

ronsimpson

Well-Known Member

Most Helpful Member

• Oct 20, 2012

• #6

I think a simple motion sensor will work.
https://www.zilog.com/index.php?option=com_cutsheet&task=view&cid=6&id=6&Itemid=95

 

M

mdredmond

New Member

• Oct 20, 2012

• #7

There was an article I read a number of years ago about a "radar" made with off-the-shelf parts "for about $15" that could detect a person's breathing. It was developed by a scientist at Livermore Labs. If you Google it you'll probably find it.

I'll bet you have the same idea I did when I read the article That application was patented by another party unconnected to the Livermore guy.

 

G

GT-Janos

New Member

• Oct 21, 2012

• #8

Hi Ron,

You have been very helpful! Thanks,

GT-Janos

 

G

GT-Janos

New Member

• Oct 21, 2012

• #9

Hi mdredmond,

I tried to google the article, but couldn't find the item you recommended. Maybe my search criteria:
"radar" made with off-the-shelf parts "for about $15" was not the best.

Regards,

GT-Janos

 

jpanhalt

Well-Known Member

Most Helpful Member

• Oct 21, 2012

• #10

Try "human detection radar."

This may be close, but I am not IEEE and can't access: **broken link removed**

John

 

K

kubeek

Well-Known Member

Most Helpful Member

• Oct 21, 2012

• #11

Well that article describes the basic function, but since it operates at 2.4GHz and doesn´t show much more than theory, I don´t think it is much use for a normal hobbyist.
Anyway I may be able upload a screenshot somewhere if somebody wants it.

 

M

mdredmond

New Member

• Oct 21, 2012

• #12

Try: http://ipo.llnl.gov/?q=technologies-micropower_impulse_radar

You'll need to dig for the scientist's name and from there can find the patent, aka 'build instructions' .

Good luck!

 

alec_t

Well-Known Member

Most Helpful Member

• Oct 21, 2012

• #13

I'm new to the community, so how does it work work with your "experimental" circuitry?

Click to expand...

I design circuits, then simulate their operation with the aid of LTSpice. Theoretically they work, but simulation can never be 100% accurate. I usually don't build them for real.....I leave that for others to do .