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31  Using Arduino / Project Guidance / Re: RTC and sunrise / sunset programming on: October 23, 2013, 10:20:25 am
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Have you considered a photocell?

A photocell in combination with an RTC would seem like a good idea i.e. set time bands for sunset and for sunrise and then use the photocell within those timebands to decide when the event has ocurred. That solves issues of local geography (is the site in a valley or on a mountaintop) and also difficulties with light intensity (full moons, dark days, shadows from movable objects).
32  Community / Bar Sport / Re: US shutdown - safe mode on: October 23, 2013, 08:23:27 am
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none. even the representant. So how about a mixed system?

The Representatives do of course reflect the biases of the people who voted for them and probably are not knowlegable on even a limited range of subjects. However they are being paid to do a job, they have time to concentrate on it and you just have to hope they do the best they can taking expert advice.

Your mixed system sounds like chaos.

The only reasonable and workable alternative I can see to Representative Democracy is Benign Dictatorship - of course absolute power corrupts absolutely.
33  Community / Bar Sport / Re: why do leaves reflect green light? on: October 23, 2013, 08:10:55 am
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So that begs the question of all the wavelengths .. why green? (Yes yes i know WHY scientifically) but not from an evolution design point.... the green is right smack in the middle of the visible wavelengths, also our strongest visual color.

There are probably two answers to this;
  • Evolution does not have an objective, random chance just resulted in green not being used
  • It could be that the chemical/physical tricks and tools to use green don't exist or, if they do, have negative consequences. For example if you need a chemical that does not exist in soil or is damaging to the plant or whose reactions require too much energy then evolution cannot use it

Read somewhere that photosynthesis may be making use of quantum mechanical processes to allow reactions to take place. This is attracting the attention of the quantum computing people and of course could be important if you can get some reactions to take place at lower energies than classical chemistry suggests.
34  Community / Bar Sport / Re: US shutdown - safe mode on: October 23, 2013, 07:01:50 am
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but that way (democratic republic) many people that KNOW  and WANT make a meaningfull vote cannot do it.

The population of the USA is about 310M. In that population the percentage of people that have detailed knowledge on any one topic will be vanishingly small. How many people have real indepth knowledge about genetics and stem cells, evolution, global warming, foreign policy, finance etc. etc.

If you think that the elected representatives do a bad job then don't forget its the adults in the 310M that put them there. Unless you can devise a better system Democratic Republic is the best around at the moment.
 
35  Using Arduino / Project Guidance / Re: I want my stepper motor to switch speed while traveling (not acceleration wise) on: October 23, 2013, 05:56:08 am
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What I want it to do basically is to first moveTo2500 at the current speed 200 then after 2500 I want it to increase speed to 400.

The title of your post includes "not acceleration wise".

You seem to be trying to instantly double the step speed of your stepper motor. Whether not you can do this will depend on the torque your stepper generates and the mass of the object it is moving. In reality the stepper motor does have to accelerate the mass, if the mass is too large for the motor it will skip.
36  Using Arduino / Project Guidance / Re: measuring the wind speed on: October 23, 2013, 05:44:57 am
The simplest way to measure wind speed is probably using a cup anemometer with three cups;
http://en.wikipedia.org/wiki/Anemometer

Once you have built it all you need to do is measure the speed of rotation of the shaft.

The location of your anemometer will be important to the readings you get. Ideally you want it mounted so that the wind is hitting it horizontally most of the time so you want to avoid areas where the wind would be turbulent or in the windshadow of trees, buildings etc.
37  Community / Bar Sport / Re: US shutdown - safe mode on: October 23, 2013, 05:13:54 am
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The American people didn't directly vote on the law.  The representatives did that.  We have a democratic republic  in the US, not a direct democracy.

The American people did vote for it. The Democrats had ObamaCare as a policy, people voted for the Democrats who then implemented their policy and it was passed into Law.

The concept of a "direct democracy" is pretty much the same as "anarchy" if it involves more than a few dozen people. Individuals don't have the time, knowledge, and experience to take meaningful votes on legislation. Instead, in a democratic republic, you elect representatives to whom you delegate the power to make decisions on your behalf. When they vote for something it is you that is voting.

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I wouldn't say it's crazy.  I would say that continually running up the debt with no plan in place to stem that debt is crazy.

Of course blocking was crazy because what it did was throw away probably hundreds of millions of dollars for nothing. What blocking did was say to other countries "If you lend me money I may not pay you back". The USA still needs to borrow but of course those other contries will now charge more because the USA has self injured itself by making itself a higher risk to lend to!

I agree running up debt is a bad idea but what you need to do is stop running up the debt not make threats not to pay back what you have already borrowed.

38  Community / Bar Sport / Re: US shutdown - safe mode on: October 22, 2013, 06:57:35 am
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In the USA, we just spend the money whether we have it or not.

That may be true but, having bought something you don't just turn round and say "I have spent too much so I am not going to pay my bills", which is exactly what the recent row was about.

Raising the debt ceiling was about paying for things already bought. Just the threat of not paying will have cost the USA hundreds of millions of dollars as now higher rates will have to be paid for loans.

Also some people may not like ObamaCare but it was a Democratic policy which the American people had the opportunity to vote on and which became Law - trying to repeal it (at great cost) by linkage to un unrelated topic is just crazy.
39  Using Arduino / Project Guidance / Re: use arduino to help my daughter on: October 22, 2013, 06:35:11 am
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In essence, her the toes are still flat on the ground, but the sole is lifted around 45+ degrees above horizontal.

That is more what I imagined the first time round, the ballet reference threw me off track.
I still think there might be some merit in exploring a tilt switch but i have no idea how they would behave with all messy movements a foot makes.

The piezo idea might work, but I think it would be a hard one to crack.

The idea of force sensors has a much greater chance of success as it is simpler (though still involves a lot of technical issues). There will be a clear difference in force between the heel and toe sensors and the absolute magnitude might allow aother actions to be excluded e.g. skipping, running, using stairs which I imagine would all generate larger forces than walking.

Whatever way you go good luck.

40  Using Arduino / Project Guidance / Re: use arduino to help my daughter on: October 21, 2013, 09:58:01 am
I think some design compromise is required. Trying to find a shoeless solution is a step too far.

If you keep shoes then a solution using force sensors as suggested by Mike sound like it could be practical. Are we missing an even simpler solution though. I had assumed that the girl is walking on tip-toe, but there has been mention of ballet is she actually walking "on-point" i.e. with the sole of her shoe vertical? That would be quite extreme and very different from most normal foot motion. If so could a solution just using a tilt switch be possible? Could a switch detect a foot at between say 80-90deg but not respond if the foot is at lower angles but being shaken about?

41  Using Arduino / Programming Questions / Re: Sending and Receiving Location using Google Maps on: October 21, 2013, 09:12:02 am
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The main problem is, we don't know how to integrate Google Map in Arduino.

To start forget about Arduino, software etc. and work out exactly how you would do things by hand.

Unfortunately your posting is not really very clear about what you want to do, I find the references to "numbers" confusing.
42  Using Arduino / Project Guidance / Re: use arduino to help my daughter on: October 21, 2013, 08:54:59 am
There is a section of the site on E-Textiles and Craft.
It is bound to have tips on making the electronics wearable and unobtrusive.
http://forum.arduino.cc//index.php?board=13.0

I liked the idea of the pressure sensors in the shoes but you would have all the issues of fitting things into multiple pairs (and you want a solution that will work without shoes).

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I was planning to stick the piezo directly to the inside of the box, so in essence it would detect if the box is vibrating continuously (such as  walking) then assign a threshold for that vibrating value to trigger the vibrator motor.

I think it will be quite tough to use a method like this to reliably detect toe walking compared with running (on toes), skipping, going up and down stairs etc. - but the only way to find out is to try smiley

You should experient on yourself first. I suggest you aim for a system that avoids false positives. Far better for your daughter to be accurately reminded 50% of the time, and to take heed, than to be frequently wrongly warned and very quickly learn to ignore the device.

43  Community / Bar Sport / Re: What happens when they rebel? on: October 21, 2013, 08:01:22 am
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Ha!  There's a license for that?
The licenses don't actually exist as yet but Deer Trail, Colo. has received over 900 requests for licenses at $25 each.

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Still, the Federal Aviation Administration isn’t amused, issuing a note last summer when the ball started rolling pretty much warning people to keep their weapons holstered if a drone happens by, permit or no. ”Shooting at an unmanned aircraft could result in criminal or civil liability, just as would firing at a manned airplane,” said the government agency.

http://newsfeed.time.com/2013/09/06/want-a-license-to-hunt-drones-this-colorado-town-just-might-give-you-one/
44  Community / Bar Sport / Re: US shutdown - safe mode on: October 21, 2013, 07:48:48 am
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So, just because you exist then that places an interminable obligation on me to make sure that you, and yours are provided for?

I think one of the basic things a society does is to take care of the sick (which could be any one of us at any time). If you don't do that do you have a society?

Potentially the cheapest and most uniform way of providing health care is via the tax system where we collectively pool our money.

The objective of Insurance Companies is to make a profit. That has two major consequences firstly it extracts money (the profit) from the system secondly, to maximise profit, it denies insurance to those who really need it.

If you have ever tried to make a claim on any kind of insurance you will be aware it is a very one-sided system.
45  Community / Bar Sport / Re: Malware warning ... is this genuine or not? on: October 21, 2013, 07:12:32 am
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And the worst thing is when I get emails from myself!

It is disconcerting when that first happens, but it is a good thing as it empasises that you cannot trust the addresses displayed in emails. No validation is done to confirm that the FROM address in an email is actually where the email came from.

It is also worth remembering that the REPLY-TO address can be different to the FROM address (and also has no need to be related to where the mail actually came from).

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