Planet Monitoring System Using Sensors

Hello all,

My group and I are designing a planet monitoring system that measures moisture, sunlight, temperature, and pH, cataloging this information in a database, and providing an interface that allows users to easily use this info to improve their gardening techniques.

We have a few questions that we've developed to help us pare down our vision, and I'd be really grateful if any of you could answer some or all of them. Feel free just to address whichever question strikes your fancy. (Hopefully, there is a question that does.) Any other advice is also helpful.

Thanks

Engineering Questions
How will we deal with the effects of temperature on the pH measurement?
What are some ways to provide waterproofing?
What are acceptable margins of error for our sensor measurements?
What government licenses or regulations should be consulted?
What interface would be best in providing the customer with data?
Will we provide simultaneous measurements or provide them one by one through a switching mechanism?

 

We're beginning both research and designing right now, but we know more than zilch, lol. However, as undergraduate students, this is our first opportunity to actually design something, and we wanted to get some guidance from people with actual experience.

Feel free to answer our questions with questions, or with answers, or not answer at all. My goal is to use more than just data sheets and our fractured knowledge from disparate courses.

Thank you for the luck, though. I think we'll be okay.

 

[Phil Hobbs]

On 11/06/2013 08:42 AM, querida.ellis@gmail.com wrote:

Hello all,

My group and I are designing a planet monitoring system that measures moisture, sunlight, temperature, and pH, cataloging this information in a database, and providing an interface that allows users to easily use this info to improve their gardening techniques.

We have a few questions that we've developed to help us pare down our vision, and I'd be really grateful if any of you could answer some or all of them. Feel free just to address whichever question strikes your fancy. (Hopefully, there is a question that does.) Any other advice is also helpful.

Thanks

Engineering Questions
How will we deal with the effects of temperature on the pH measurement?
What are some ways to provide waterproofing?
What are acceptable margins of error for our sensor measurements?
What government licenses or regulations should be consulted?
What interface would be best in providing the customer with data?
Will we provide simultaneous measurements or provide them one by one through a switching mechanism?

So in other words you know zilch about your own product. Good luck with
that.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

This was all pretty helpful. Thanks.

Unfortunately, I copied and pasted the exact same message to a number of places, so there's been a lot of suggestions concerning NASA.

On Wednesday, November 6, 2013 3:00:17 PM UTC-6, Tim Wescott wrote:

On Wed, 06 Nov 2013 05:42:34 -0800, querida.ellis wrote:



Hello all,



My group and I are designing a planet monitoring system that measures

moisture, sunlight, temperature, and pH, cataloging this information in

a database, and providing an interface that allows users to easily use

this info to improve their gardening techniques.



I'm hypothesizing here, but you don't speak English as a native language,

you started with your language's word for "dirt", that became

"earth" (which is a fair, if overly polite word for "dirt"), that became

"Earth", and "Earth", as a proper noun, names a planet.



You mean "soil monitoring system".



(Here's a quick breakdown:

"dirt" is soil that no one cares about.

"soil" is what you grow plants in.

"earth" is "soil" in the garden of a rich man.

the "ground" is where you find "dirt", "soil" and/or "earth".



Clothing can get dirty or soiled, but not earthed. Oddly

enough, electrical circuits can get grounded, or if they're

on British soil, earthed. But a dirty electrical circuit

isn't shorted to ground, it's just got unwanted stuff on it.



If this doesn't help, I hope it at least amuses.)



We have a few questions that we've developed to help us pare down our

vision, and I'd be really grateful if any of you could answer some or

all of them. Feel free just to address whichever question strikes your

fancy. (Hopefully, there is a question that does.) Any other advice is

also helpful.



Thanks



Engineering Questions How will we deal with the effects of temperature

on the pH measurement?



You know more than me. I assume that you have a pH sensor in mind, and

that it is temperature sensitive? Why not just measure the temperature

and compensate? If the pH itself changes with temperature, I'd suggest

just logging them both together.



What are some ways to provide waterproofing?



Many. If you have a sufficient budget you can just buy waterproof cases

and connectors. If this only has to work for a term you can leave the

bottom of your case open to the air and make sure that all the cables

exit downward (so that no drips can find their way into connectors).

Your stuff will experience slow corrosion, but your goal here (I assume)

is to graduate before anything rusts away.



What are acceptable margins of error for our sensor measurements?



That's for you to decide. In a commercial environment, that question

would be answered by the product line manager, who would (or damned well

_should_ know what the market wants). In general terms, narrow enough to

be useful. For gardening, I suspect that the answer is "pretty wide".



Perhaps the best thing to do if you can is to see if there are any botany

professors (you'll find them in the biology department). Find one in his

office, tell him what you're doing, tell him what information you need

and ask for a book recommendation. You'll either get that or you'll get

a list of the precisions you need.



It's best if you're doing the above that you choose a hypothetical market

segment -- i.e. amateur gardeners, farmers, or researchers. Each of

these three communities will, in general, have rising needs for precision.



What government licenses or regulations should be consulted?



Where are you on this planet? Are you going to sell these or just make

one as a demonstration? In the US, as long as you're below some magic

voltage (I think it's 42 volts, but I know 12V is safe), you aren't

releasing any toxic chemicals, and you aren't making any promises about

accuracy, then you don't really come under any laws.



What interface would be best in providing the customer with data?



That question is too open. Here again, in a commercial environment that

would be the job of the product line manager to decide, possibly in

consultation with engineering to get an idea of what costs what.



Will we provide simultaneous measurements or provide them one by one

through a switching mechanism?



This is another question for your hypothetical product line manager, in

consultation with engineering about costs. ADC chips are cheap these

days, so it may be cheapest to _not_ switch things, but just get more ADC

channels.



--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com

 

[Phil Hobbs]

On 11/06/2013 12:59 PM, querida.ellis@gmail.com wrote:

We're beginning both research and designing right now, but we know more than zilch, lol. However, as undergraduate students, this is our first opportunity to actually design something, and we wanted to get some guidance from people with actual experience.

Feel free to answer our questions with questions, or with answers, or not answer at all. My goal is to use more than just data sheets and our fractured knowledge from disparate courses.

Thank you for the luck, though. I think we'll be okay.

Ah, okay, homework. That makes more sense.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510

hobbs at electrooptical dot net
http://electrooptical.net

 

[Tim Wescott]

On Wed, 06 Nov 2013 13:17:47 -0500, Phil Hobbs wrote:

On 11/06/2013 12:59 PM, querida.ellis@gmail.com wrote:
We're beginning both research and designing right now, but we know more
than zilch, lol. However, as undergraduate students, this is our first
opportunity to actually design something, and we wanted to get some
guidance from people with actual experience.

Feel free to answer our questions with questions, or with answers, or
not answer at all. My goal is to use more than just data sheets and our
fractured knowledge from disparate courses.

Thank you for the luck, though. I think we'll be okay.


Ah, okay, homework. That makes more sense.

Cheers

Phil Hobbs

Or senior project work -- that's what it sounds like to me.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Tim Wescott]

On Wed, 06 Nov 2013 05:42:34 -0800, querida.ellis wrote:

Hello all,

My group and I are designing a planet monitoring system that measures
moisture, sunlight, temperature, and pH, cataloging this information in
a database, and providing an interface that allows users to easily use
this info to improve their gardening techniques.

I'm hypothesizing here, but you don't speak English as a native language,
you started with your language's word for "dirt", that became
"earth" (which is a fair, if overly polite word for "dirt"), that became
"Earth", and "Earth", as a proper noun, names a planet.

You mean "soil monitoring system".

(Here's a quick breakdown:
"dirt" is soil that no one cares about.
"soil" is what you grow plants in.
"earth" is "soil" in the garden of a rich man.
the "ground" is where you find "dirt", "soil" and/or "earth".

Clothing can get dirty or soiled, but not earthed. Oddly
enough, electrical circuits can get grounded, or if they're
on British soil, earthed. But a dirty electrical circuit
isn't shorted to ground, it's just got unwanted stuff on it.

If this doesn't help, I hope it at least amuses.)

We have a few questions that we've developed to help us pare down our
vision, and I'd be really grateful if any of you could answer some or
all of them. Feel free just to address whichever question strikes your
fancy. (Hopefully, there is a question that does.) Any other advice is
also helpful.

Thanks

Engineering Questions How will we deal with the effects of temperature
on the pH measurement?

You know more than me. I assume that you have a pH sensor in mind, and
that it is temperature sensitive? Why not just measure the temperature
and compensate? If the pH itself changes with temperature, I'd suggest
just logging them both together.

> What are some ways to provide waterproofing?

Many. If you have a sufficient budget you can just buy waterproof cases
and connectors. If this only has to work for a term you can leave the
bottom of your case open to the air and make sure that all the cables
exit downward (so that no drips can find their way into connectors).
Your stuff will experience slow corrosion, but your goal here (I assume)
is to graduate before anything rusts away.

> What are acceptable margins of error for our sensor measurements?

That's for you to decide. In a commercial environment, that question
would be answered by the product line manager, who would (or damned well
_should_ know what the market wants). In general terms, narrow enough to
be useful. For gardening, I suspect that the answer is "pretty wide".

Perhaps the best thing to do if you can is to see if there are any botany
professors (you'll find them in the biology department). Find one in his
office, tell him what you're doing, tell him what information you need
and ask for a book recommendation. You'll either get that or you'll get
a list of the precisions you need.

It's best if you're doing the above that you choose a hypothetical market
segment -- i.e. amateur gardeners, farmers, or researchers. Each of
these three communities will, in general, have rising needs for precision.

> What government licenses or regulations should be consulted?

Where are you on this planet? Are you going to sell these or just make
one as a demonstration? In the US, as long as you're below some magic
voltage (I think it's 42 volts, but I know 12V is safe), you aren't
releasing any toxic chemicals, and you aren't making any promises about
accuracy, then you don't really come under any laws.

> What interface would be best in providing the customer with data?

That question is too open. Here again, in a commercial environment that
would be the job of the product line manager to decide, possibly in
consultation with engineering to get an idea of what costs what.

Will we provide simultaneous measurements or provide them one by one
through a switching mechanism?

This is another question for your hypothetical product line manager, in
consultation with engineering about costs. ADC chips are cheap these
days, so it may be cheapest to _not_ switch things, but just get more ADC
channels.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[George Herold]

On Wednesday, November 6, 2013 2:47:15 PM UTC-5, Tim Wescott wrote:

On Wed, 06 Nov 2013 13:17:47 -0500, Phil Hobbs wrote:



On 11/06/2013 12:59 PM, querida.ellis@gmail.com wrote:
We're beginning both research and designing right now, but we know more
than zilch, lol. However, as undergraduate students, this is our first
opportunity to actually design something, and we wanted to get some
guidance from people with actual experience.

Feel free to answer our questions with questions, or with answers, or
not answer at all. My goal is to use more than just data sheets and our
fractured knowledge from disparate courses.

Thank you for the luck, though. I think we'll be okay.


Ah, okay, homework. That makes more sense

Cheers


Phil Hobbs
Or senior project work -- that's what it sounds like to me.

Does sound more like a senior project. My only advice is to start small. And do it in parts.
1.) get the data logger working.. maybe just record time of day.
2.) then add one simple measurement (maybe temperature)
3.) then bring up other pieces.


I guess I've just seen failures where the first timer tries to get the whole thing working at once, (which never happens) and then doesn't know how to 'de-bug' it.

George H.

--



Tim Wescott

Wescott Design Services

http://www.wescottdesign.com