Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: mgaro on September 09, 2009, 03:09:15 PM

Title: need help with sensors.
Post by: mgaro on September 09, 2009, 03:09:15 PM
Hi
I'm looking place where I could buy ready or to hire someone to make two sensors, first will react on change of tone of color or light going throw transparent plastic object, and second sensors reacts on change of relative position/movement of the object. Those sensors have to be a battery operates. Any advice and help is welcome, I'm very new to society of robots.

Thank You
Garri
[email protected]
Title: Re: need help with sensors.
Post by: Joker94 on September 09, 2009, 07:57:45 PM
well with the light sensor do you want to sense particular colours or just a chane in intensity of the light. if you just want to sense intensity of light you could just use a photo sell hooked up to a microcontroller or similar sensor.]

And to track the object fepending on the distance you can use a sharp infared sensor mounted on a servo if you want a larger sensing area.

What is your end product going to be?
Title: Re: need help with sensors.
Post by: mgaro on September 10, 2009, 04:17:07 PM
Hi
For one of my School projects I need to create a prototype with sensors, which will detect fooling two conditions: I have transparent container full with white liquid, when container is empty than sensor sends a signal to a wireless reviser on which light bulb/sound goes on. Other condition is: if I move a container to new position from beginning position, just slight change of ¼ of inch, than sensor sends a signal too. Please let me know where I could get these sensors and other parts so I build it myself or maybe you could help me to build or sagest who could build it for me, let me know how much it could cost.
Thank you
Garri
[email protected]
Title: Re: need help with sensors.
Post by: mgaro on September 10, 2009, 04:29:06 PM
The final Project is to create a prototype that will detect empty or full container and change of position, relation of beginning to new position. I don’t know how to do that, have no knowledge of sensors.
Anybody could help
Title: Re: need help with sensors.
Post by: Joker94 on September 10, 2009, 10:34:32 PM
well if you don't have to sense distancec sharp infared will work for direction

and to sens  if there is any liquid in the container you could use a photo cell which will tell when the light is blocked there for contains liquid.

Where do you live,the reason i ask is so i can post some links from local/suitable online shops with some suitable sensors
Title: Re: need help with sensors.
Post by: mgaro on September 11, 2009, 11:07:27 AM
well if you don't have to sense distancec sharp infared will work for direction

and to sens  if there is any liquid in the container you could use a photo cell which will tell when the light is blocked there for contains liquid.

Where do you live,the reason i ask is so i can post some links from local/suitable online shops with some suitable sensors

Hi
Thank You so much for your response, I live in Brooklyn, NY, USA
Is a photo sensor that you are suggesting would work if it’s no light in room, I would need to find sensors that work in dark and light room too and how bid and heavy those sensors are, I need sensors that are very small, and could operate on a battery. Do you know anybody who could help me in building the sensors system, or maybe I could get reedy made parts that easy and simple to put together for someone like me, new to robots and electronics?
Thanks
Garri
Title: Re: need help with sensors.
Post by: Joker94 on September 11, 2009, 06:03:27 PM
A photo cell would only sense if there is liquid in the container if there is an out side light source.

i can not think of a sensor that would work in the dark of hand but one option is to mount a 3 or 5mm LED close to a photo cell to give it a light source untill the it is blocked by the liquid.

and you can get really small photo cells, close to 4x9 mm and 1mm hight.

Here is what a photo cell is and some different sizes.

http://www.futurlec.com/Photocells.shtml (http://www.futurlec.com/Photocells.shtml)
Title: Re: need help with sensors.
Post by: mgaro on September 17, 2009, 01:31:05 PM
A photo cell would only sense if there is liquid in the container if there is an out side light source.

i can not think of a sensor that would work in the dark of hand but one option is to mount a 3 or 5mm LED close to a photo cell to give it a light source untill the it is blocked by the liquid.

and you can get really small photo cells, close to 4x9 mm and 1mm hight.

Here is what a photo cell is and some different sizes.

http://www.futurlec.com/Photocells.shtml (http://www.futurlec.com/Photocells.shtml)

I will need a help in making photo cell work with the battery, could you sagest if I could get ready made kit that use a photo cell, or somebody can do it for me a payment
‘well if you don't have to sense distance sharp infared will work for direction’ What I need is a sensor that will detect change of new position of the container. Change of angel for example.
Could you sagest where I could get these type of sensors
Title: Re: need help with sensors.
Post by: Joker94 on September 17, 2009, 06:58:05 PM
Here are some infared sensors, these are ready to plug into you MCU and will do what you want to do with some code.

http://www.sparkfun.com/commerce/categories.php?c=139 (http://www.sparkfun.com/commerce/categories.php?c=139)
Title: Re: need help with sensors.
Post by: Joker94 on September 17, 2009, 07:30:51 PM
As for the photo cell you will probably have to build it your self. and they may have to be inside the tank with a water proof layer on the out side.

It should not be that hard to build, the LED will need a resistor for protection, and the photoresistor will also need a photo resistor so theroticaly that is all you will have to build and the rest you can use premade off the shelf boards.

If you want some off the shelf MCU's that are cheaper have a look at these(the axons are a better investment and will be better over the long run but if your doing a school project they are prbably not in you price range).   -Arduino Boards   -http://www.littlebirdelectronics.com/collections/arduino (http://www.littlebirdelectronics.com/collections/arduino)

As for the transmitter and reciever packages there are hundreds you could use.
Some thing like this may be ok for your purposes but i have not used it before but i am thinking of tring it out.http://www.sparkfun.com/commerce/product_info.php?products_id=691 (http://www.sparkfun.com/commerce/product_info.php?products_id=691)

I'll post someshematics if you want but over all it is all pretty easy and should not be to hard and you only need to build 1 thing, the rest is plug and play. You don't have to use the examples i have given they are just an out line for what you can use.
Title: Re: need help with sensors.
Post by: Joker94 on September 17, 2009, 08:34:53 PM
Here are some simple shematics

1) Is the photo cell circuit, the resistor value should be around 220R? The two pins should be plugged into the i/o pins of the MCU.

Also read thishttp://www.societyofrobots.com/schematics_photoresistor.shtml (http://www.societyofrobots.com/schematics_photoresistor.shtml)

2)Here is a LED circuit that can just run off a battery.
Title: Re: need help with sensors.
Post by: SmAsH on September 18, 2009, 02:34:56 AM
Those circuits don't looks too right? Why not just use the ones admin has in that link you posted?
They only use one I/O pin...
As for noticing movement, must it follow the object too? if so, i would highly recommend a servo mounted sharp ir sensor with a microcontroller running something similar to the stampy code that admin wrote.
Stampy, Sumo Robot (http://www.youtube.com/watch?v=vbhMuPF0Qj4&feature=player_embedded#)
Title: Re: need help with sensors.
Post by: Joker94 on September 18, 2009, 02:41:25 AM
good point, and admins has documentation on how to build it, put it together.
Title: Re: need help with sensors.
Post by: mgaro on September 30, 2009, 04:21:12 PM
Hi
I'm looking place where I could buy ready or to hire someone to make two sensors, first will react on change of tone of color or light going throw transparent plastic object, and second sensors reacts on change of relative position/movement of the object. Those sensors have to be a battery operates. Any advice and help is welcome, I'm very new to society of robots.

Thank You
Garri
[email protected]


Hi
I need a help with a photo sensor, I got one of the light sensor detectors (Maxxima-MLS-10), but I need to reverse the way it works, I need it  when sensor detects light in room LED light is goes up and when it’s dark in room LED light not working. Anybody knows how to do that. Please let me know. 
Thank You
garri

the light sensor detectors (Maxxima-MLS-10) I got
http://www.amazon.com/Maxxima-MLS-10-Occupancy-Sensor-Light/dp/B000FI2YHY/ref=pd_sim_k_1 (http://www.amazon.com/Maxxima-MLS-10-Occupancy-Sensor-Light/dp/B000FI2YHY/ref=pd_sim_k_1)