hi every body

can you help me

i am a student and i need a measuring project who can help me

i am sorry but the person who will help me please make the project full of every thing because it is the first project i will do

the project that i want i need to be uniqe project

maybe like that

have a PIC and have say 5 or so photo-diodes (with transimpedance amps) around a room and when the light in the room (ie all 5 sensors) drop below a set level you could then have the PIC send a signal and ?
what you do with that signal... you would have to have an isolated sensor since IF you then turned a light on all the sensors would sa yTOO-Bright!!! and you would turn the light off

maybe like that or anything please help me i need you

 

Yes with pleasure we can help you

the proj will/should be done by you

Y u need a PIC for that??

Anything..

?????? :shock:

 

ok how can you all help me
forgot every thing that i said

 

I have had a chat with him and this is what I have assertained

He needs to do a Uni semester project on sensing/measurement (learning abt OPAMPS and all that)

want to do it on light


so has a cct for a transimpedance amplifer (using a photo diode)
Have 3 such Trans amps around a room that the output then feeds a summing amp with a gain of 1/3 to get the average light in the room

Why 3? why not (makes the project more interesting)

Now this AVERAGE light level to maybe act on something, like make a lamp brighter (do-able)


I was thinking there could be a problem that this will then make the room brighter and the sensors will tell the control to dim the light, IF control is fine it will control the light around a mean.

BUT what if at teh summing amp it was setup to be a weighted summing-amp with a higher influence soming from one particular sensor (one pointing out of a window)

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Nothing is impossible.
Once a problem is realised, the rest is just details

 

Yes if the room illumination is controlled depending on the feedback of more sensors , then u will need a weighed o/p from the sensor. or use multiple lights to illuminate each part of the room.

 

Now what u need to know??

 

ok i come back

can you help me ? how?

some links about some project ideas

and thank you all

 

Now what u need to know??

 

i want to know if you can help me with some project ideas ? understand me?

 

ok..u need a proj.
help this guy ..
http://www.electro-tech-online.com/v...asc&highlight=

 

ok thank you AKG

i want every member in this forum to put links that interested in measurment projects
and i thank you all

 

Hi Nourtamer,
There is a project on the web that measures the moisure of a potted plant's soil. It is supposed to dim its LED when the soil is moist then brighten the LED gradually as it dries. Many people complained that it didn't dim, its LED was on dimly or off. They said it didn't work with some ICs with a 3V battery. With an IC that worked at 3V, it stopped when the battery voltage dropped a little as it was used. Its battery didn't last very long.

I fixed its lack of dimming by adding a capacitor and a resistor so it dimmed using PWM. I fixed its problems of a low battery voltage by using a 74HCxx IC. I made its LED much brighter when it wasn't dimmed by adding two transistors. I added a blinking feature so a smaller battery lasts a very long time.

You could find a measuring project on the web that doesn't work, then fix it like I did.

Attached Images

plants_circuits.png (6.3 KB, 372 views)

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Uncle $crooge