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4k7
05-08-2009, 08:04 AM
Guys our Institute is organizing a themed hardware event called"Sensors and Computer Interfacing". So suggest our team something. We are planning to build a wireless mobile device, but we are having a problem that which type of sensors should we use. :?:

suhasm
05-08-2009, 08:10 AM
What kind of a wireless mobile device ? What does it do?
I think you can probably use either infrared (but limited by line of sight) , RF pairs or bluetooth modules (bulky).....

RF pair would be a good option. But even that isnt quite small enough to make a "mobile device"....

If line of sight is not a problem , then use IR , it will be compact...

4k7
05-08-2009, 08:23 AM
Sorry for less info. :D BTW we are planning to make a device that collects info. and is wirelessly connected to a computer that may store, process or display the collected info. But we are confused about what are the specific sensors that can be used for such purpose. :?:

suhasm
05-08-2009, 10:27 AM
What is the range you expect?
What kind of info are you collecting?
And what is the kind of data that you will be transmitting?
If it is complex/high speed then you cannot use infrared.

You will have to use either RF or blue tooth i guess.

As far as i know, bluetooth modules with inbuilt stack support are not available in india. It will be hideously expensive if you try to import it.

I think you can try using RF pairs.

What have you thought of till now?

MohitM
05-08-2009, 08:34 PM
I have this idea for a long time... But I just do not have the time to do anything about it, in the short and the mid term. Anyway, here goes...

Its a wireless Weather Station, having two units. The mobile station is placed outside complete with temperature, relative-humidity, atmospheric pressure, wind-speed etc. sensors and a cell phone. The microcontroller reads all the sensors and passes it to the cell. The cell phone then sends periodically (say, once every 30 seconds) through SMS all this raw data to the base station which has another cell phone. This receiver cell phone connects to a PC which processes and displays all the relevant data. It could do this through a webpage that could be viewed remotely on the net.

The cell phones could have a plan that allows unlimited free SMS.

I am sure there are commercial products like this out there.

4k7
05-09-2009, 10:51 AM
I have this idea for a long time... But I just do not have the time to do anything about it, in the short and the mid term. Anyway, here goes...

Its a wireless Weather Station, having two units. The mobile station is placed outside complete with temperature, relative-humidity, atmospheric pressure, wind-speed etc. sensors and a cell phone. The microcontroller reads all the sensors and passes it to the cell. The cell phone then sends periodically (say, once every 30 seconds) through SMS all this raw data to the base station which has another cell phone. This receiver cell phone connects to a PC which processes and displays all the relevant data. It could do this through a webpage that could be viewed remotely on the net.

The cell phones could have a plan that allows unlimited free SMS.

I am sure there are commercial products like this out there.

Thanks dude we were also planning for the same thing but we were confused on the sensors to be used. As you've mentioned the sensors like temp. ,humidity, atm. pressure, wind speed etc. Are they readily available in market? BTW I'm not in India but am in Nepal. :D

MohitM
05-09-2009, 04:02 PM
In the electronics industry, you will never have a problem if your quantity requirement is either less than 5 or more than 100,000. If its somewhere in between, I don't know.

Try Farnell or RS Electronics. They should not be too expensive, only 5-10 times what the real price is. :) But, then you just need a few!

Good luck!

4k7
05-10-2009, 04:00 PM
Ah BTW should I post this thing here or not ? We are planning a wireless communication between PC and the outdoor station. Is RF good for the purpose? Are there any specific things to be taken care during the project or any problems(I think I'll post it later) :D .

4k7
05-17-2009, 05:10 PM
Ah...now commencing our project. :D
BTW what type of sensors are available for measurement for the atmos. pressure. :?:
And we are using the HH10D as humidity sensor, how is this? Is it harder to interface ....

OFF TOPIC: For wireless communication, serial or parallel port??? Reasons??

4k7
05-17-2009, 05:15 PM
Ah...now commencing our project. :D
BTW what type of sensors are available for measurement for the atmos. pressure. :?:
And we are using the HH10D as humidity sensor, how is this? Is it harder to interface ....

OFF TOPIC: For wireless communication, serial or parallel port??? Reasons??

suhasm
05-17-2009, 08:18 PM
How can you do parallel wireless transmission?
Its not possible unless you have 8 (or more) different frequency RF pairs at each end.
I have never heard of data being transferred wirelessly in parallel.

Serial is the only practical solution.
You can use USART if you have only 2 devices.
Or perhaps you can use something like I2C if you have many devices.

suhasm
05-17-2009, 08:25 PM
HH10D gives a frequency based output. I guess that will make it a bit hard to interface. You will have to set up a timer in a uC which is clocked externally through the output from the sensor. You could read the timer register value every 0.1s or so , and perform the appropriate operations on the value to get the humidity.
BTW , how much did you pay for the sensor?
What are the the sensors you managed to get?

suhasm
05-17-2009, 08:29 PM
Have you taken a look at this thread? Take a look at it , it might help :
http://www.electro-tech-online.com/electronic-projects-design-ideas-reviews/36692-weather-station-sensors.html

BTW , an atmos. pressure sensor is available :
http://www.hoperf.com/pro/hp01d.html

4k7
05-18-2009, 05:35 AM
How can you do parallel wireless transmission?
Its not possible unless you have 8 (or more) different frequency RF pairs at each end.
I have never heard of data being transferred wirelessly in parallel.

Serial is the only practical solution.
You can use USART if you have only 2 devices.
Or perhaps you can use something like I2C if you have many devices.

yes I know that we can't send it in parallel fashion. But due to limited knowledge on serial transmission we are planning to convert serial to parallel and vice - versa . Is that a good idea?? :?:


BTW , how much did you pay for the sensor?

We need not buy any thing, the college is providing us with any accessories we needed.


What are the the sensors you managed to get?
Till now we have only managed the same old temp. sensor, HH10D Humidity sensor only . But am planning to get the HP01D(thank you) now. :idea:


HH10D gives a frequency based output. I guess that will make it a bit hard to interface. You will have to set up a timer in a uC which is clocked externally through the output from the sensor. You could read the timer register value every 0.1s or so , and perform the appropriate operations on the value to get the humidity.

Regarding this I'll be posting the problems faced during the lab work. I guess I will get suggestions from you people. So thanks in advance.

suhasm
05-18-2009, 09:16 AM
yes I know that we can't send it in parallel fashion. But due to limited knowledge on serial transmission we are planning to convert serial to parallel and vice - versa . Is that a good idea?? Question

You dont have an option. You have to convert the serial data into parallel format in order to store it or to operate upon it. All uCs and IC's are basically parallel in nature. They need the data to be converted to parallel format before using it. You cannot directly use serial data.