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Photo optic event counter needed

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easytim

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Hello,

I'm looking for a counter that will count up, only one count each time a hand goes into a box and touches a meteorite exhibit at a science center.

A counter is needed that will keep its count information even if power has been taken away, yes non-volatile memory. I want to keep track how many times a meteorite has been touch by the public, there is 1.2 million vistors each year. Maybe only 200,000 per year will trigger the counter or more.

If you don't know where I can get something like this. I hope someone will know who will, I really want to make this happen

Please help me in this matter.


Sincerely,
Tim
 
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A 99¢ solar powered calculator fed by a long life battery instead of relying on its solar cells will keep the counting alive for very, very long time.

Introducing the value 1 (one) on memory, if the hand-in-the-box sensing circuit triggers the calculator M+ key, you have a digital counter. ;)

Miguel
 
Warning!

A 99¢ solar powered calculator fed by a long life battery instead of relying on its solar cells will keep the counting alive for very, very long time.

Introducing the value 1 (one) on memory, if the hand-in-the-box sensing circuit triggers the calculator M+ key, you have a digital counter. ;)

Miguel

The $1.00 calculators I have found lately have NO solar cell, just a picture of one!
But they do have a battery; aren't those Chinese SOB's clever.
 
A counter is needed that will keep its count information even if power has been taken away.

So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?
 
The $1.00 calculators I have found lately have NO solar cell, just a picture of one!
But they do have a battery; aren't those Chinese SOB's clever.

A guy at work bought a portable USB charger (to charge USB devices from a battery anywere) that had a few unwired coils and relay things inside to make it look complicated and a piece of rusted metal to add weight.
 
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So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?

What accuracy do you expect adding 1 + 1 in a calculator?

A calculator is not an estimator. :D
 
What accuracy do you expect adding 1 + 1 in a calculator?

A calculator is not an estimator. :D


It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this.
 
So you need a non-volatile memory.

How accurately do you need to read the count? Better than 1%? 5%?


It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this
 
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It does not need to be perfect, it would be a cool idea after 300,000 people have touched this counter display be seen by those who come to touch it.

A big read out, digital display for all to see. Maybe a big sign that says you are the 300,000 person to touch this, next person, you are the 300,001 person to touch this

OK.
Non-volatile memory.
Six or seven digit display.
Each digit resolvable (no rounding)
Photocell sensing.

This runs off the wall outlet or batteries?
Indoor environment?
High ambient lighting?
Any adverse environmental stuff - moisture, vibration, etc.?
 
OK.
Non-volatile memory.
Six or seven digit display.
Each digit resolvable (no rounding)
Photocell sensing.

.



This runs off the wall outlet or batteries?
Indoor environment?
High ambient lighting?
Any adverse environmental stuff - moisture, vibration, etc.?



.
It needs to run on 110vac wired to a junction box with a battery back-up.

This counter would work **broken link removed** with 12vdc but I need a photocell circuit to trigger counting or a touch alarm circuit.

I can do a 12vdc 7 AH lead acid battery with a battery charger to keep battery charged, they use these in home alarms.

That lead acid battery and charger combo I think would work well to power it. Unit will be used in an Indoor environment, not a brightly lighted room, no moisture or vibration.

Maybe I can use this 12vdc touch alarm circuit to trigger counting **broken link removed**

The idea here is when you finger touches the hole where the Mars Meteorite is (around that hole is a small metal ring that triggers a count) it counts up one


.
 
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Hi easytim,

did you notice that the counter you mentioned has only four digits for display? To count up to 999,999 six digits are required.

I suggest making an own design cascading six CD40110 decimal counters. To clock the counter you might use an IR-barrier arranged the way that only hands touching the metorite can trigger the counter.

For display you might use Kingbright 7-segment LEDs of 100mm height. (package height 122mm)

Hans
 
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Hi easytim,

did you notice that the counter you mentioned has only four digits for display? To count up to 999,999 six digits are required.

I suggest making an own design cascading six CD40110 decimal counters. To clock the counter you might use an IR-barrier arranged the way that only hands touching the metorite can trigger the counter.

For display you might use Kingbright 7-segment LEDs of 100mm height. (package height 122mm)

Hans



.



Please read more, you can use two, then it will give it 8 digits. Thats some great ideas you have given me THANKS






.
 
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Just curious:

What/where in St. Louis is the place where this would be? I remember visiting a really fine children's science museum there about 25 years ago.

Obviously, there are many ways to accomplish what you are asking about, beginning with cascaded decade counters and going up all the way to--gasp! :eek: --a microprocessor.

I think optical beam interruption (visible light or infrared) may be a better choice than a touch sensor.

You might consider a little bit of delay time (a very few seconds) before the sensor (whichever you use) is able to be triggered again.

There will always be people who will touch the thing repeatedly just to watch the numbers change. Since your sensor can't tell people apart, perhaps the sign should read "This meteorite has been touched [numeric display] times since [date installed]!"
 
Hi easytim,

I've already designed a schematic and layout for the six-digit-counter. Is the 4-digit-counter built the way that two of them fit together to make them look like one display?

I also have a circuit and PCB-layout for an IR-barrier to be used for object recognition in a can crusher.

This is what the 100mm display looks like. Power supply connector and RESET-button are on the right hand side. The counter & decoder ICs are underneath the display.

Regards

Hans
 

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If the interval between the first person touching the thing for the first time and the second person touching the thing for the first time
is 10 seconds or so,
you might need a retriggerable one-shot to lock out the counter for this interval.
 
Just curious:

What/where in St. Louis is the place where this would be? I remember visiting a really fine children's science museum there about 25 years ago.

Obviously, there are many ways to accomplish what you are asking about, beginning with cascaded decade counters and going up all the way to--gasp! :eek: --a microprocessor.

I think optical beam interruption (visible light or infrared) may be a better choice than a touch sensor.

You might consider a little bit of delay time (a very few seconds) before the sensor (whichever you use) is able to be triggered again.

There will always be people who will touch the thing repeatedly just to watch the numbers change. Since your sensor can't tell people apart, perhaps the sign should read "This meteorite has been touched [numeric display] times since [date installed]!"





At the St. Louis Plantaruim.


I was thinking of putting a 15 second delay on counter. So it only counts up once every 15 seconds, touch it once then you need to wait 15 seconds for it to count up one more time.
I know now it will be triggered more than once by one person , but it still counts for how many times it has been touched. It still counts for a touch, its not really how many people touched it, but how many times it has been touched that will be counted. Your right a sign that says how many times it has been touched, not how many people




.

.
 
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