beginner help
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I am looking to weigh human beings and ouput the info through the serial
interface using my bs2. I bought the stampworks kit, but I obviously had
something specific in mind...I want to move a lot faster than following each
project in the book. I know this is a relatively simple idea, but all the
documentation I have found is way too complicated for the level I currently
function at. Can anyone point me toward a simple explanation for this
process?
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interface using my bs2. I bought the stampworks kit, but I obviously had
something specific in mind...I want to move a lot faster than following each
project in the book. I know this is a relatively simple idea, but all the
documentation I have found is way too complicated for the level I currently
function at. Can anyone point me toward a simple explanation for this
process?
_________________________________________________________________
Send and receive Hotmail on your mobile device: http://mobile.msn.com
Comments
a potentiometer (slide type, or rotary type with rack-and-pinion to
drive it). You can use the POT command to read the output, but
you'll have a heck of a time keeping it calibrated. The DEBUG
command will get the data to show on your PC screen, or you can use
the SEROUT command to send the data to a terminal program of some
sort. There are VB scripts available to read the data also. See
http://www.rentron.com/VisualBasic.htm
Of course this won't get you past input variations due to
temperature. I think I saw something in the Stamp Manual that
discusses adjusting for temp, but I can't remember where.
Then there is the problem of the 'subject' bouncing on your homemade
scale. This would require some kind of dampening out circuit.
Other than that, all I can say is Good Luck.
Don
--- In basicstamps@y..., "amanda ervin" <ale2121@h...> wrote:
> I am looking to weigh human beings and ouput the info through the
serial
> interface using my bs2. I bought the stampworks kit, but I
obviously had
> something specific in mind...I want to move a lot faster than
following each
> project in the book. I know this is a relatively simple idea, but
all the
> documentation I have found is way too complicated for the level I
currently
> function at. Can anyone point me toward a simple explanation for
this
> process?
>
>
>
>
> _________________________________________________________________
> Send and receive Hotmail on your mobile device:
http://mobile.msn.com
>
>I am looking to weigh human beings and ouput the info through the
serial
>interface using my bs2. I bought the stampworks kit, but I obviously
had
>something specific in mind...I want to move a lot faster than
following each
>project in the book. I know this is a relatively simple idea, but
all the
>documentation I have found is way too complicated for the level I
currently
>function at. Can anyone point me toward a simple explanation for
this
>process?
>
First you have to find a way to convert the physical force imparted by
a persons weight into something that can be measured electronically.
There may be commercial digital scales or some sort of weight sensors
that give you could interface the stamp to. Or you could rig up
something yourself.
If you built your own, a potentiometer might be a good sensor to use.
Potentiometers are those knobs that are used to control volume on
hi-fi's. As a potentiometer turns its amount of turn can be monitored
using the RCTIME command and a very simple circuit. Check out the
Stamp manual (the one in PDF format) and look under RCTIME. You can
also get pots that slide left/right instead of turning, like those
that were used in old TV volume controls.
So maybe you can work out a way to make a pot move when a persons
weight is transferred to it? Maybe you could work out a way to hook a
pot up to a normal set of scales??? Just some ideas....
Paul Lugger
__________________________________________________________________
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>
>Original message from: "amanda ervin" <ale2121@h...>
>>
>>I am looking to weigh human beings and ouput the info through the
>serial
>>interface using my bs2. I bought the stampworks kit, but I
obviously
>had
>>something specific in mind...I want to move a lot faster than
>following each
>>project in the book. I know this is a relatively simple idea, but
>all the
>>documentation I have found is way too complicated for the level I
>currently
>>function at. Can anyone point me toward a simple explanation for
>this
>>process?
>>
>First you have to find a way to convert the physical force imparted
by
>a persons weight into something that can be measured electronically.
>
>There may be commercial digital scales or some sort of weight sensors
>that give you could interface the stamp to. Or you could rig up
>something yourself.
>
>If you built your own, a potentiometer might be a good sensor to use.
>Potentiometers are those knobs that are used to control volume on
>hi-fi's. As a potentiometer turns its amount of turn can be monitored
>using the RCTIME command and a very simple circuit. Check out the
>Stamp manual (the one in PDF format) and look under RCTIME. You can
>also get pots that slide left/right instead of turning, like those
>that were used in old TV volume controls.
>
>So maybe you can work out a way to make a pot move when a persons
>weight is transferred to it? Maybe you could work out a way to hook a
>pot up to a normal set of scales??? Just some ideas....
>
>Paul Lugger
>
If money is no problem and you want a very professional/accurate
measure, you should go the commercial scale/sensor route.
Otherwise.....
It might be possible to use a normal human weighing scale. If you
could gain access to where the meter is on the scale(usually behind a
little glass window) you might be able to mechanically join it to a
potentiometer, so that when the meter turns it also turns the pot. But
the meters do usually look kind of weak and they might not be strong
enough to turn a pot. Check out the local second hand shop and grab
some very cheap scales to experiment on.
Paul Lugger
__________________________________________________________________
Get your free Australian email account at http://www.start.com.au
measurement. They cost in the $10 to $30 range. I think they have a 3 point
sensor for weighing purposes. The pbasic code below is an example how to use
the "rctime" command to do a force measurement.
Chuck
'setup using a Tekscan Flexiforce sensor, m/n A101
'BS2 with 1 uf cap at 5v charge and 220 ohm to pin 0
'6/29/01
result var word
p con 0
gosub LCDINIT
lcdout 0,1,[noparse][[/noparse]"Flexiforce A1011"]
aa:
high 15
pause 1
rctime 15,1,result
if result<655 then xx
result=(65535-result)/100
debug ? result
lcdout 0,192,[noparse][[/noparse]dec result," grams "]
goto aa
xx:
lcdout 0,192,[noparse][[/noparse]"0 grams "]
pause 200
goto aa
LCDINIT 'initialize LCD
lcdcmd p,48 'set function
pause 5
lcdcmd p,48
pause 1
lcdcmd p,48
pause 1
lcdcmd p,32
pause 1
lcdcmd p,44
pause 1
lcdcmd p,8 'display off
lcdcmd p,12 'display on
lcdcmd p,6 'set mode
return