BoEBot & Polariod 6500
Can anybody help me, with what seems to be a simple problem, but I've been working on it for the last 24 hours and can not for the life of me find a solution.
It's basically this I have a home made BoEBoT fitted with a Polariod 6500, but every time the 6500 'fires' both servo's turn very slightly and both in different directions. The Stamp II is obviously picking up interference from the 6500 board, but how do you prevent it.
Please help me soon I'm not going to my bed until I get this fixed.
Many, many thanks in advance
John
It's basically this I have a home made BoEBoT fitted with a Polariod 6500, but every time the 6500 'fires' both servo's turn very slightly and both in different directions. The Stamp II is obviously picking up interference from the 6500 board, but how do you prevent it.
Please help me soon I'm not going to my bed until I get this fixed.
Many, many thanks in advance
John
Comments
Are you using the default battery source for the BoeBot (4 AA's)? IF you are, the problem is more likely the Polaroid 6500 unit , simply because of the high power drain it requires every time you fire the sonar. You need a separate power supply for the Sonar, or at least a more powerful one for the BoeBot, however the size of the BoeBot limits how large of a battery you could use.
Original Message
From: john & lisa
To: basicstamps@egroups.com
Sent: Thursday, November 09, 2000 8:23 PM
Subject: [noparse][[/noparse]basicstamps] BoEBot & Polariod 6500
Can anybody help me, with what seems to be a simple problem, but I've been working on it for the last 24 hours and can not for the life of me find a solution.
It's basically this I have a home made BoEBoT fitted with a Polariod 6500, but every time the 6500 'fires' both servo's turn very slightly and both in different directions. The Stamp II is obviously picking up interference from the 6500 board, but how do you prevent it.
Please help me soon I'm not going to my bed until I get this fixed.
Many, many thanks in advance
John
-William
·
Original Message
From: john & lisa
To: basicstamps@egroups.com
Sent: Thursday, November 09, 2000 8:23 PM
Subject: [noparse][[/noparse]basicstamps] BoEBot & Polariod 6500
Can anybody help me, with what seems to be a simple problem, but I've been working on it for the last 24 hours and can not for the life of me find a solution.
It's basically this I have a home made BoEBoT fitted with a Polariod 6500, but every time the 6500 'fires' both servo's turn very slightly and both in different directions. The Stamp II is obviously picking up interference from the 6500 board, but how do you prevent it.
Please help me soon I'm not going to my bed until I get this fixed.
Many, many thanks in advance
John
> battery pack and has the 33000uf capacitor in place. The
> Polariod 6500 is running of a separate PP3 volt battery.
> Both negative's from the pack are tied together, as I've seen
> in the past (from this email page) problems when running two
> separate power packs to drive separate sensors etc.
> At the moment the stamp has not been programmed to drive the
> servo's just the 6500 calibration programme. I know the 6500
> board is causing the interference
Hi John,
It is also important to bypass the ATN input to the stamp. That is an
prime entry point for weirdness. Put a resistor, say 3.3 kohms, from pin 3
of the StampII to ground at pin 4. You might also add a capacitor there in
parallel with the resistor, say 0.1uF.
Do you also have a fat capacitor across the 6500 board itself? You can
also try moving around the point where the negatives tie together. The
important thing is avoid any current flow from the 6500 common to the Stamp
wiring.
-- Tracy Allen
http://www.emesystems.com
Once again many thanks in advance
Looking forward to your reply's
John
Original Message
From: Tracy Allen <emesys@c...>
To: <basicstamps@egroups.com>
Sent: Friday, November 10, 2000 6:57 PM
Subject: [noparse][[/noparse]basicstamps] BoEBoT & Polariod 6500
> > home made Board of Education is running of the usual 4 x AA
> > battery pack and has the 33000uf capacitor in place. The
> > Polariod 6500 is running of a separate PP3 volt battery.
> > Both negative's from the pack are tied together, as I've seen
> > in the past (from this email page) problems when running two
> > separate power packs to drive separate sensors etc.
> > At the moment the stamp has not been programmed to drive the
> > servo's just the 6500 calibration programme. I know the 6500
> > board is causing the interference
>
> Hi John,
>
> It is also important to bypass the ATN input to the stamp. That is an
> prime entry point for weirdness. Put a resistor, say 3.3 kohms, from pin
3
> of the StampII to ground at pin 4. You might also add a capacitor there
in
> parallel with the resistor, say 0.1uF.
>
> Do you also have a fat capacitor across the 6500 board itself? You can
> also try moving around the point where the negatives tie together. The
> important thing is avoid any current flow from the 6500 common to the
Stamp
> wiring.
>
> -- Tracy Allen
> http://www.emesystems.com
>
>
>
>
It was worth a try. I also tried the different tie in points for the ground wire but this has no effect.
I just have to keep trying. The only ideas I can come up with is putting the 6500 board in a metal enclosure, but there just is not enough room on the BoEBoT for this.
Thanks anyway Tracy.
John
Original Message
From: john & lisa
To: basicstamps@egroups.com
Sent: Friday, November 10, 2000 8:49 PM
Subject: [noparse][[/noparse]basicstamps] BoEBoT & Polariod 6500
Thanks to Tracy Allen with your ideas regarding interference from the 6500 board. I tried your idea but it seemed to have no effect what's so ever.
It was worth a try. I also tried the different tie in points for the ground wire but this has no effect.
I just have to keep trying. The only ideas I can come up with is putting the 6500 board in a metal enclosure, but there just is not enough room on the BoEBoT for this.
Thanks anyway Tracy.
John
Thanks again
John
Original Message
From: David Peterson
To: basicstamps@egroups.com
Sent: Saturday, November 11, 2000 7:49 AM
Subject: Re: [noparse][[/noparse]basicstamps] BoEBoT & Polariod 6500
I don't know if you've seen it or not, but Dennis Clark has a webpage about using sonar boards hacked from Polaroid cameras. It's at http://www.verinet.com/~dlc/sonar/dlcsonar.html·if you want to take a look for any other ideas. He has code for the BS2 and 68HC11 SBasic.
Original Message
From: john & lisa
To: basicstamps@egroups.com
Sent: Friday, November 10, 2000 8:49 PM
Subject: [noparse][[/noparse]basicstamps] BoEBoT & Polariod 6500
Thanks to Tracy Allen with your ideas regarding interference from the 6500 board. I tried your idea but it seemed to have no effect what's so ever.
It was worth a try. I also tried the different tie in points for the ground wire but this has no effect.
I just have to keep trying. The only ideas I can come up with is putting the 6500 board in a metal enclosure, but there just is not enough room on the BoEBoT for this.
Thanks anyway Tracy.
John
board.
>I tried your idea but it seemed to have no effect what's so ever.
>It was worth a try. I also tried the different tie in points for the
ground
>wire but this has no effect. I just have to keep trying. The only ideas I
>can come up with is putting the 6500 board in a metal enclosure, but there
just
>is not enough room on the BoEBoT for this.
>Thanks anyway Tracy.
Hi John,
Oh, well. Can you detach the 6500 completely from the stamp and make it
ping on its own power supply and its own wiring. Have a program running on
the stamp at the same time. Does the operation of the 6500 still affect
the stamp?
If so, then it is time to work on that shielding. That might be as simple
as some heavy duty aluminum foil (with some plastic insulator!?) wrapped
around it and grounded to the chassis.
If you can ping the 6500 without it affecting the stamp, then the problem
is more than likely coming in through the wiring. Put resistors in the
leads that go from the stamp pins to the 6500. Surges can sneak in through
the signal lines. Also, run the power line through a shield. Also, run
the signal and excitation lines through a shield. You can purchase metal
braided shield that you can attach to ground at one end only. Keep at it!!
-- Tracy
distance from the stamp board and it did sort the problem, so a metal
enclosure it looks like it'll have to be, but getting a custom built box is
impossible due to size limitations, and getting sheet metal out here in
Cyprus is impossible, and so is sheet plastic, so making my own custom box
will be hard to do. I'm currently trying thin card with tin foil glued to it
(mostly my fingers at the mo) I'll keep you posted.
Many Thanks
John
Original Message
From: Tracy Allen <emesys@c...>
To: <basicstamps@egroups.com>
Sent: Sunday, November 12, 2000 6:23 PM
Subject: [noparse][[/noparse]basicstamps] BoEBoT & Polariod 6500
> >Thanks to Tracy Allen with your ideas regarding interference from the
6500
> board.
> >I tried your idea but it seemed to have no effect what's so ever.
> >It was worth a try. I also tried the different tie in points for the
> ground
> >wire but this has no effect. I just have to keep trying. The only ideas I
> >can come up with is putting the 6500 board in a metal enclosure, but
there
> just
> >is not enough room on the BoEBoT for this.
> >Thanks anyway Tracy.
>
> Hi John,
>
> Oh, well. Can you detach the 6500 completely from the stamp and make it
> ping on its own power supply and its own wiring. Have a program running
on
> the stamp at the same time. Does the operation of the 6500 still affect
> the stamp?
>
> If so, then it is time to work on that shielding. That might be as simple
> as some heavy duty aluminum foil (with some plastic insulator!?) wrapped
> around it and grounded to the chassis.
>
> If you can ping the 6500 without it affecting the stamp, then the problem
> is more than likely coming in through the wiring. Put resistors in the
> leads that go from the stamp pins to the 6500. Surges can sneak in
through
> the signal lines. Also, run the power line through a shield. Also, run
> the signal and excitation lines through a shield. You can purchase metal
> braided shield that you can attach to ground at one end only. Keep at
it!!
>
> -- Tracy
>
>
>
>
>