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stamp_demon
05-30-2005, 12:23 PM
I had a very stupid question that I thought I might ask. I was wondering what the possible usses of a digital compase could be in relation to robotics, and the basic stamp. I can imagine a few, but can't quit see how they could be implemented. One idea I had was to use a compase along with sonar. When the sonar finds objects within a certain range, the compase location could then be writen to eprom for latter use. But with such a small amount of memory, I can't see how that can acually be implemented without some other memory source. And I did see a great idea on the parallax site demestrating the idea of rf comunication with the bot and a pc. I'm sure there are a million other idea's..
· I'm just trying to find a way of using it with limited resorces. Thank you all very much _Duane

Chris Savage
05-30-2005, 01:18 PM
Hello,

·· Limited resources is always a matter of perspective.· It's a rare application that uses all the Stamp Modules resources.· In any event to address your question, the module could be used for navigating based on compass heading.· You're talking about storing data, but it doesn't really need to for that.· It could be just trying to maintain a heading.··Another application would be to help align a solar panel prior to the sun being out to track.· And, if you read the PDF file for the new compass module it lists several possible applications.


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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

Loopy Byteloose
05-30-2005, 06:59 PM
Someone mentioned using the digital compass for part of a weather monitor - the wind direction indicator.

It had never occurred to me and I was looking at setting up a wind direction indicator by using a set of hall-effect transistors and having them monitor a magnet on the shaft of the wind direction indicator.

Using the digital compass really simplifies the construction and programing. I guess that you will still use a shaft with a magnet on the end, but you don't have to develop a board with all those hall-effect transtors and get its positioning perfect.

By the way, you still would use just one hall-effect transistor on the wind speed detector. That would be a separate device and much simpler.

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G. Herzog in Taiwan

Orion
05-30-2005, 11:32 PM
That a good idea for the compass, wind direction. How would you keep the wiring from twisting up into knots though? Use a single magnet on the end of the shaft to manipulate the compass?

Chris Savage
05-31-2005, 04:31 AM
Orion,

·· One way would be a self-contained, sealed enclosure, perhaps battery powered (But not necessarily), sending the information via RF Link.·



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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

KenM
05-31-2005, 09:16 AM
Slip ring.

Orion said...
That a good idea for the compass, wind direction. How would you keep the wiring from twisting up into knots though? Use a single magnet on the end of the shaft to manipulate the compass?

Danny
06-01-2005, 12:59 AM
Do you know a source to purchase manufactured slip rings?
Or do I have to go to a junk yard and strip a steering column?
I can think of a ton of projects that would be SOOOO much easier with slip rings.

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"Never create anything you can't control"
"The amount of intelligence on the planet is fixed... the population is growing"

Loopy Byteloose
06-01-2005, 09:10 AM
Somehow you all seem a bit confused.

No need for slip rings. You use the magnet attached to the wind vane shaft to 'comunicate' position·of the windvane TO·the STATIONARY·electronic compass.

The compass with wires remains stationary. What is turned is the Wind Vane with an attached magnet. This would sit above the compass and not touch it. So there are not any wires to twist.

Chris' comment about an RF link does not really apply to your question. But, after you build the weather station you may want to use a 'wireless' RF link to get data into your computer. The big advantage is to avoid lightning strikes entering your computer via the weather station. Being atop a pole or building, these devices seem to attract lightning strikes that can be sent along a regular RS-232 interface.

Still, it is cheaper to build your first proto-type with the RS-232 interface. After it is working, you can add the RF link.

By the way Danny, you comment about population growing and intelligence being fixed implies that we are getting dumber. Do you really believe that? Or, is it a joke?

Personally, I beieve the human condition is a lot more complex than that, but maybe we never learn enough. Part of life will always be a mystery, and part of it is always a struggle.

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G. Herzog in Taiwan

Post Edited (Kramer) : 6/1/2005 3:45:04 PM GMT

Chris Savage
06-01-2005, 09:20 AM
Kramer said...(trimmed)
Somehow you all seem a bit confused.
Chris' comment about an RF link does not really apply to your question. But, after you build the weather station you may want to use a 'wireless' RF link to get data into your computer. The big advantage is to avoid lightning strikes entering your computer via the weather station. Being atop a pole or building, these devices seem to attract lightning strikes that can be sent along a regular RS-232 interface.
Actually, my comment applied perfect.· The OP was asking about getting the wires tangled up.· If it was for a portable weather station, it could use a battery/solar-powered wind vane/thermometer mounted on a pivot.· No wires would be connected to anything.· The module could transmit data via an RF link serially.

As for the lightning issue...Many of these that I see are not mounted on a roof, but rather a rear deck, thereby negating the possibility of lightning strikes, especially when you consider that lightning tends to take the least path of resistance to ground, and that is generally the highest point as well.

Also, placing a magnet near the compass may not be a good idea.· Some can actually be damaged in this way, and it would be hard to get accurate readings.

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Chris Savage
Parallax Tech Support
csavage@parallax.com (mailto:csavage@parallax.com)

Loopy Byteloose
06-01-2005, 11:44 PM
Don't forget wind speed.

Parallax has nearly everything [the compass as a wind direction sensor, but detecting the magnet's axis·-- not operating as a true compass].

The temperature and humidity sensor.

You still would have to build another tachometer sensor for the wind speed.

~~

BY THE WAY, there are no stupid questions here - we all have something to learn.· Im my case it is how to communicate more clearly [so I guess I gave a stupid answer]http://forums.parallax.com/images/smilies/smilewinkgrin.gif

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G. Herzog in Taiwan

Post Edited (Kramer) : 6/1/2005 3:47:46 PM GMT