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gshubham96
10-07-2010, 01:15 AM
HI,
I want to know if there is any sensor that can sense human body through heat maybe?

maddy_nish
10-07-2010, 12:49 PM
Hi..
It can be done using PIR sensor.. U can even select the sensor based on the range u want.. Check this link. It has got quite a lot of info .. http://www.ladyada.net/learn/sensors/pir.html

pratheek
10-08-2010, 07:50 AM
You can use a PIR senor. They can sense any moving body with a different heat signature than the surroundings. They are used in a lot of commercial products too.
You can get one here http://probots.co.in/index.php?main_page=product_info&cPath=9&products_id=180

You can use sound sensors to detect footsteps, speech, etc. Or you can also place a simple obstacle sensor at the entrance of the required sensing area.

gshubham96
10-08-2010, 11:44 AM
thanks for the reply,all of you :D
but I want a sensor which can only detect human being :( .

asimov_18
10-09-2010, 12:50 AM
Hi,
You can use a web cam and write an image processing code in matlab for face detection. I don't know much about matlab or the image processing code so dont ask me how to do it!!!!

Asimov

akshay66
10-09-2010, 12:49 PM
Hi,

Tell us abouy your project and application that why do you want to detect human body only??? Although what asimov is saying is fantastic for such a task.

gshubham96
10-09-2010, 05:00 PM
i'm building a robot car which can search for human body in remote places such as jungles,etc.
I want a low-cost solution.

asimov_18
10-09-2010, 11:33 PM
Hi,
I guess you ask DRDO for it. They would surely be working on something like this!!!!!


Asimov

gshubham96
10-10-2010, 12:06 AM
I wanted to know that if there is any heat sensor available which can detect human heat.

allbits
10-10-2010, 10:26 AM
You cannot have a low cost solution for this.
If you really want this thing to work PROPERLY -
(by properly, I mean - you show the device to an area and it detects just the human beings and nothing else, in environments like jungles, WITHOUT ERROR), you will need lots of money.

You will need an Array of PIR sensors, or a PIR camera. Sensing heat at a distance involves the use of IR rays.. since heat is 'radiated', not conducted.

Last time we bought a decent PIR camera(not to be confused for a PIR sensor) for a gallery, was for 6.5Lakhs INR.

Image processing fails well in noise conditions like a jungle, while it works fine in closed rooms and all. If you are trying to build a proposal for the military or something, forget it for the time being, you need to learn lot more to design decent stuff. It is not enough that you take the output from a sensor and use a comparator to switch an LED. There is lot more than that. You need to custom build things.

I did not mean to discourage, just telling you things the way it is at the moment.


And yes, there are no sensors which detects 'humans' as such, sensors detect signals, it is for us to decide if that is from a human or a cat or a vampire.

gshubham96
10-10-2010, 11:57 AM
thank to all.:D

akshay66
10-10-2010, 12:38 PM
I'm not getting it???

Are you making it autonomous or manual???

If its autonomous ans suppose you get your human detecting sensor then how will your robot move in jungle, on what basis there will be a whole lot of obstacles and no lines to follow??

If its manual then you don't need a sensor you just need a normal CCTV camera and Infrared camera with a couple powerful white LEDs for light. The video taken by the two can be streamed using a powerful transmitter.With the help of the two videos on your screen you can detect a human in jungle.The normal CCTV camera will help you to see whats around your bot and you can move your bot accordingly.With the help of an infrared camera you can detect the heat of a human.

You can even make a semi autonomous in which you control it manually and a sensor detects human body and gives you signal.

NONE OF THE ABOVE SOLUTIONS ARE LOW COST AND BE READY TO SPEND ATLEAST 1 YEAR AND THEN ALSO IT WON'T BE AS GOOD FOR REAL LIFE SITUATION BUT ATLEAST TRY YOU WILL MAKE IT ONE DAY AND FORUM IS ALWAYS OPEN FOR BEGINNERS :)

gshubham96
10-10-2010, 02:26 PM
thanks akshay , but jungle was just an example, i meant off road places or even in collapsed building for search and rescue program.
And I am making a semi-autonomus robot as you mentioned.

Ulhas
10-13-2010, 03:43 PM
Detection of Living / Alive body can be possible by IR based remote temprature measurment Gun. Based on normal human body temperature you can take crude decision about presense of human body
Of course it may detect the animals,trees etc. You can use PIR sensor to distinwish moving / stationary object.
If this is OK then follow the suggestions given by most of member to confirm presence of humans
I don't think it will be done by using a single sensor or algorithm

docel
10-14-2010, 07:43 AM
A PIR sensor will do - for the Jungle- since the human will be the ONLY source of heat there...apart from tigers and such. PIR sensors are optimised for human body heat , but they work as movement sensors rather than static human sensors.
The thing is to use the PIR as a scanner so that the PIR internal differential sensors 'detect' the presence of a human heat source. This is tricky since you have to 'scan' the sensor around a horizontal arc.

[ Now, most student projects are less innovation-more gimmick kind of thing aimed at provoking immediate Ohhhhs & AHhhs towards instant celebrity status. Also , the student project is invariably powered by 'cheap' components.:D
It may not be possible in this project.
There CAN be cheaper and simpler solutions for this project, but the problem for the solution must be very clear or the solution will just be a dummy gimmick.
Any project must be thoroughly analysed and evaluated BEFORE implementation. A wise rule is 70% planning and 30% implementation , as far as time is concerned. This will ensure success that is meaningful and more useful ]

gshubham96
10-14-2010, 11:20 PM
thanks every body..
But I need more help in my robot tracks.please check the following link:
http://www.roboticsindia.com/showthread.php/3660-Tank-Treads?p=19444#post19444

tsa.ananth
08-28-2012, 11:20 AM
HI,
I want a sensor to detect the presence of human body inside sand by heat,blood flow or any thing else....
I wish to design a device to detect people struck in sand due to earth flow,earth quack...,so as to rescue them fastly,is it possible?
plz replay....

docel
08-28-2012, 03:23 PM
The only known method is Sub-surface Radar / Ground penetrating Radar.
It could be VHF/UHF/ Microwave or Ultrasonic, depending upon practical and financial constraints.
A lot of DSP techniques are needed to isolate and resolve the images form received data. It works exactly like MRI and Ultrasound used in Medical diagnosis.
I fooled around with some junk ultrasound scanners, but couldn't continue far enough to achieve anything.

The principle is simple enough - just imagine how we " see" things. Light reflection, color filtering and Depth perception using Binocular vision ( Triangulation).
If the Light rays ( which are Electro-Magnetic Radiations) are substituted with "penetrating" radiations like Ultrasonic , RF and Magnetic radiations, then we have a ground penetrating Radar that can be visualized on a screen.
Sound waves can be used, but they are quite destructive, at the power levels needed for proper reflection through solid materials.

vikas
08-29-2012, 04:43 PM
Such systems exist -

Google GSSI LifeLocator , they use Ultra Wide Band radars. You might look more into it if you plan to build something similar.

docel
08-30-2012, 09:00 AM
Thanks Vikas. These are commercial right now.
I saw something like this being used at Bhuj during our Earthquake Relief work by a French Relief team. It wasn't as effective as the present systems though and could only penetrate loose soil. The GSSIs of today see through collapsed RC concrete and solid rocks.
Most of the Electronics are available off the shelf. It is the extensive proprietary Software that does the job.