Here's a good design for an indoor robotic navigation system.

http://www.sdrobotics.org/publications/index.html

I had also considered using an acoustic long-baseline system and measuring
travel times to fixed acoustic transponders.

thankyou very much bob
this system can be used to provide absolute fixes
..followed by inertial guidance system. the system
seems easy to deploy 

--- Bob Waters <b_waters@b_wa...> wrote:
> Here's a good design for an indoor robotic
> navigation system.
> 
> http://www.sdrobotics.org/publications/index.html
> 
> I had also considered using an acoustic
> long-baseline system and measuring
> travel times to fixed acoustic transponders.
> 
> 


__________________________________

Using a GPS re-radating kit will not work very well in
this application.  As I understand it the GPS is being
used to find the location indoors, however the
re-radiated signal will always decode to the position
of the external antenna used to receive the off-air
signals.  

I would also question the suitability of GPS in this
application without all the complications of using
differential GPS and a second receiver at a known
location to provide the correction values.  The module
that I use (u-blox) has an accuracy of 50% within 4m
of true position when it has a clear view of the sky. 
This would make for a pretty big air hockey table ;-)

Ian  

http://www.satamatics.com

 --- Greg Maki <gmaki@gmak...> wrote: > Hi
Harshit,
> 
> If you need to receive GPS signals indoors, there
> are GPS re-radiating kits
> available. We purchased this one and it works great.
> There a little pricey,
> but it sure beats having to take everything outside
> to do your testing!
> 
> http://www.navtechgps.com/supply/rerad.asp
> 
> HTH,
> 
> Greg
> ----- Original Message ----- 
> From: "harshit suri" <suri_list@suri...>
> To: <msp430@msp4...>
> Sent: Tuesday, October 28, 2003 10:36 PM
> Subject: Re: [msp430] Hardware architectural
> decisions
> 
> 
> > Hi Everyone
> >
> > thankyou all for your replies. Al thankyou for
> your
> > advice. Could you please give me some links /
> > documents for your INS + GPS implementation
> > this is an indoor robot. autonomous and it hovers
> on
> > top of a air hockey table using the principle of
> air
> > bearings
> > i am using an air hockey table to simulate the
> > frcitionless environment of space in 2Dimensions.
> > I really dont know if ill be able to use gps as
> its in
> > door but its my first draft of design so it might
> > change. could you please share any design docs
> > /implementation of your INS system
> > have u interfaced MEMS gyros + MEMS accelerometer
> to
> > the MSP430 ?
> >
> > the objective of the robots are to cooperate to
> build
> > a structure.so they fly around catch onto things
> and
> > then cooperate to construct structures :-)
> >
> > once again thanks for your help everyone
> > cheers
> > Harshit Suri
> >
> > __________________________________
> > 
> >
> >
> > .
> >
> >
> >
> > ">http://docs.yahoo.com/info/terms/
> >
> >
> 
> 
> ------------------------ Yahoo! Groups Sponsor
> 
> .
> 
>  
> 
> ">http://docs.yahoo.com/info/terms/ 
> 
>  

________________________________________________________________________
Want to chat instantly with your online friends?  Get the FREE Yahoo!
Messenger http://mail.messenger.yahoo.co.uk

I use a MSP430F1121A and it is usually in  low current applications. I 
normally switch power to external chips only when I need them to conserve 
power. However, I now have a problem with this. I have a regulator 
(TPS60240) which I provide power to via P2.5. I found the regulator was 
drawing too much current in my circuit ( some 25mA with no load on it.). I 
set up the regulator by itself and it draws about 200uA with no load and at 
3.0 volts which is about right. I then use the FET and switch power to the 
regulator. When it is not switched high, the current is about 55uA and when 
I switch it high it is 16.6mA! Again this is with no load. The TPS60240 has 
2 charge caps (1uF each) and an input and output cap (each 1uF).
Can anyone provide some clues as to what is happening?


Thanks


Peter 

	According to the TI webpage, the TPS60240 is a 3.3V regulator, not 3.0V 
(TPS60243 is 3.0V).  If you're not seeing 3.3V on the output, you are
likely 
not switching the FET on completely.  Most FETS are not designed for use as a 
high-side switch, unless you're using a double FET configuration, or 
something like the Fairchild SI3861DV (an excellent little logic level FET 
switch).

	I also don't know why you need the FET at all, since the TPS60240 has an 
enable input that should put in a .1ua shutdown mode.

	--John

On Sunday 02 November 2003 22:50 pm, Peter Grey wrote:
>  I use a MSP430F1121A and it is usually in low current applications. I
>  normally switch power to external chips only when I need them to conserve
>  power. However, I now have a problem with this. I have a regulator
>  (TPS60240) which I provide power to via P2.5. I found the regulator was
>  drawing too much current in my circuit ( some 25mA with no load on it.). I
>  set up the regulator by itself and it draws about 200uA with no load and
> at 3.0 volts which is about right. I then use the FET and switch power to
> the regulator. When it is not switched high, the current is about 55uA and
> when I switch it high it is 16.6mA! Again this is with no load. The
> TPS60240 has 2 charge caps (1uF each) and an input and output cap (each
> 1uF).
>  Can anyone provide some clues as to what is happening?
>
>
>  Thanks
>
>
>  Peter
>
>
>
>
>
> 
>
>
>
>
>
>
>  .
>
>
>
>  

Hi Peter,
You obviously have something terribly wrong as the regulator is only
designed to supply 25mA max.
Drop the fet. don't need it as you can switch the enable pin from a port
directly. In shutdown mode this is only 0.1uA, with pin enabled should be
250uA. If your application requires low power consumption why not try the
TPS76933, this has higher shutdown current consumption 1uA but lower only
17uA quiescent current at full load, though this all depends what your input
voltage is as part is a fixed regulator only. Is your hardware clean? flux
residue etc.

Dennis
----- Original Message ----- 
From: "Peter Grey" <martech@mart...>
To: <msp430@msp4...>
Sent: Monday, November 03, 2003 4:50 PM
Subject: Re: [msp430] Problems with switching.


> I use a MSP430F1121A and it is usually in  low
current applications. I
> normally switch power to external chips only when I need them to conserve
> power. However, I now have a problem with this. I have a regulator
> (TPS60240) which I provide power to via P2.5. I found the regulator was
> drawing too much current in my circuit ( some 25mA with no load on it.). I
> set up the regulator by itself and it draws about 200uA with no load and
at
> 3.0 volts which is about right. I then use the FET
and switch power to the
> regulator. When it is not switched high, the current is about 55uA and
when
> I switch it high it is 16.6mA! Again this is with
no load. The TPS60240
has
> 2 charge caps (1uF each) and an input and output
cap (each 1uF).
> Can anyone provide some clues as to what is happening?
>
>
> Thanks
>
>
> Peter
>
>
>
>
> .
>
>
>
> ">http://docs.yahoo.com/info/terms/
>
>
>

At 10:07 AM 03-11-03 -0500, you wrote:
My mistake(s).
I should have said 3.3V. Also I should have said FET EMULATION TOOL, not 
FET! I used the FET because I wanted to eliminate my target board as a 
source of a problem.

Thanks


Peter
>         According to the TI webpage, the TPS60240
is a 3.3V regulator, 
> not 3.0V
>(TPS60243 is 3.0V).  If you're not seeing 3.3V on the output, you are
likely
>not switching the FET on completely.  Most FETS are not designed for use as
a
>high-side switch, unless you're using a double FET configuration, or
>something like the Fairchild SI3861DV (an excellent little logic level FET
>switch).
>
>         I also don't know why you need the FET at all, since the
TPS60240 
> has an
>enable input that should put in a .1ua shutdown mode.
>
>         --John
>
>On Sunday 02 November 2003 22:50 pm, Peter Grey wrote:
> >  I use a MSP430F1121A and it is usually in  low current applications.
I
> >  normally switch power to external chips only when I need them to
conserve
> >  power. However, I now have a problem with this. I have a regulator
> >  (TPS60240) which I provide power to via P2.5. I found the regulator
was
> >  drawing too much current in my circuit ( some 25mA with no load on
it.). I
> >  set up the regulator by itself and it draws about 200uA with no load
and
> > at 3.0 volts which is about right. I then use the FET and switch power
to
> > the regulator. When it is not switched high, the current is about 55uA
and
> > when I switch it high it is 16.6mA! Again this is with no load. The
> > TPS60240 has 2 charge caps (1uF each) and an input and output cap
(each
> > 1uF).
> >  Can anyone provide some clues as to what is happening?
> >
> >
> >  Thanks
> >
> >
> >  Peter
> >
> >
> >
> >
> >
> > 
> >
> >
> >
> >
> >
> >
> >  .
> >
> >
> >
> >  ">http://docs.yahoo.com/info/terms/

At 09:17 AM 04-11-03 +1300, you wrote:

Hi Dennis,

As in a previous post I should have said FET EMULATION TOOL.
To avoid problems with my target board I set up the FET to do the switching 
using a 1121A. When I had the regulator operating alone it was fine. When I 
try and switch power to it using the FET, I get these high currents.


all the best


Peter
>Hi Peter,
>You obviously have something terribly wrong as the regulator is only
>designed to supply 25mA max.
>Drop the fet. don't need it as you can switch the enable pin from a
port
>directly. In shutdown mode this is only 0.1uA, with pin enabled should be
>250uA. If your application requires low power consumption why not try the
>TPS76933, this has higher shutdown current consumption 1uA but lower only
>17uA quiescent current at full load, though this all depends what your input
>voltage is as part is a fixed regulator only. Is your hardware clean? flux
>residue etc.
>
>Dennis
>----- Original Message -----
>From: "Peter Grey" <martech@mart...>
>To: <msp430@msp4...>
>Sent: Monday, November 03, 2003 4:50 PM
>Subject: Re: [msp430] Problems with switching.
>
>
> > I use a MSP430F1121A and it is usually in  low current applications. I
> > normally switch power to external chips only when I need them to
conserve
> > power. However, I now have a problem with this. I have a regulator
> > (TPS60240) which I provide power to via P2.5. I found the regulator
was
> > drawing too much current in my circuit ( some 25mA with no load on
it.). I
> > set up the regulator by itself and it draws about 200uA with no load
and
>at
> > 3.0 volts which is about right. I then use the FET and switch power to
the
> > regulator. When it is not switched high, the current is about 55uA and
>when
> > I switch it high it is 16.6mA! Again this is with no load. The
TPS60240
>has
> > 2 charge caps (1uF each) and an input and output cap (each 1uF).
> > Can anyone provide some clues as to what is happening?
> >
> >
> > Thanks
> >
> >
> > Peter
> >
> >
> >
> >
> > .
> >
> >
> >
> > ">http://docs.yahoo.com/info/terms/
> >
> >
> >
>
>
>
>
>.
>
>
>
>">http://docs.yahoo.com/info/terms/

Hi Peter,
I'll assume you have set P2.5 as output and P2Sel.5 as I/O.
Is the port switching from low/hi?
The specs say what you are doing is fine and you have tested regulator
outside of micro so I have no idea.
You say the regulator uses 55uA when enable is low. Doe's this include the
micro or just regulator?
If just regulator something is wrong. Are these figures true when you
measure regulator only with enable low then hi?

good luck, hopefully somebody else can be more helpful

Dennis
----- Original Message ----- 
From: "Peter Grey" <martech@mart...>
To: <msp430@msp4...>
Sent: Tuesday, November 04, 2003 10:53 AM
Subject: Re: [msp430] Problems with switching.


> At 09:17 AM 04-11-03 +1300, you wrote:
>
> Hi Dennis,
>
> As in a previous post I should have said FET EMULATION TOOL.
> To avoid problems with my target board I set up the FET to do the
switching
> using a 1121A. When I had the regulator operating
alone it was fine. When
I
> try and switch power to it using the FET, I get
these high currents.
>
>
> all the best
>
>
> Peter
> >Hi Peter,
> >You obviously have something terribly wrong as the regulator is only
> >designed to supply 25mA max.
> >Drop the fet. don't need it as you can switch the enable pin from
a port
> >directly. In shutdown mode this is only 0.1uA, with pin enabled should
be
> >250uA. If your application requires low power consumption why not try
the
> >TPS76933, this has higher shutdown current consumption 1uA but lower
only
> >17uA quiescent current at full load, though this all depends what your
input
> >voltage is as part is a fixed regulator only.
Is your hardware clean?
flux
> >residue etc.
> >
> >Dennis
> >----- Original Message -----
> >From: "Peter Grey" <martech@mart...>
> >To: <msp430@msp4...>
> >Sent: Monday, November 03, 2003 4:50 PM
> >Subject: Re: [msp430] Problems with switching.
> >
> >
> > > I use a MSP430F1121A and it is usually in  low current
applications. I
> > > normally switch power to external chips only when I need them to
conserve
> > > power. However, I now have a problem
with this. I have a regulator
> > > (TPS60240) which I provide power to via P2.5. I found the
regulator
was
> > > drawing too much current in my circuit (
some 25mA with no load on
it.). I
> > > set up the regulator by itself and it
draws about 200uA with no load
and
> >at
> > > 3.0 volts which is about right. I then use the FET and switch
power to
the
> > > regulator. When it is not switched high,
the current is about 55uA and
> >when
> > > I switch it high it is 16.6mA! Again this is with no load. The
TPS60240
> >has
> > > 2 charge caps (1uF each) and an input and output cap (each 1uF).
> > > Can anyone provide some clues as to what is happening?
> > >
> > >
> > > Thanks
> > >
> > >
> > > Peter
> > >
> > >
> > >
> > >
> > > .
> > >
> > >
> > >
> > > ">http://docs.yahoo.com/info/terms/
> > >
> > >
> > >
> >
> >
> >
> >
> >.
> >
> >
> >
> >">http://docs.yahoo.com/info/terms/
>
>
>
>
> .
>
>
>
> ">http://docs.yahoo.com/info/terms/
>
>

At 11:27 AM 04-11-03 +1300, you wrote:

Hi Dennis
I have set P2.5 to and output and have not touched P2Sel.5 as it should be 
set up as I/O on start up. The port is switching from low to high. The 55uA 
is from the regulator only which is a little disconcerting as I would not 
expect any current. I have the enable of the regulator wired to the input 
line. That is, I switch both enable and Vin from P2.5.
If I set up the regulator with enable and Vin common and use a power supply 
to switch on these lines all is OK. I will try just switching the enable 
line and see what happens. I am wondering if I have a faulty batch of 
regulators but it is all too easy to blame the component.

Thanks for the help


Peter
>Hi Peter,
>I'll assume you have set P2.5 as output and P2Sel.5 as I/O.
>Is the port switching from low/hi?
>The specs say what you are doing is fine and you have tested regulator
>outside of micro so I have no idea.
>You say the regulator uses 55uA when enable is low. Doe's this include
the
>micro or just regulator?
>If just regulator something is wrong. Are these figures true when you
>measure regulator only with enable low then hi?
>
>good luck, hopefully somebody else can be more helpful
>
>Dennis
>----- Original Message -----
>From: "Peter Grey" <martech@mart...>
>To: <msp430@msp4...>
>Sent: Tuesday, November 04, 2003 10:53 AM
>Subject: Re: [msp430] Problems with switching.
>
>
> > At 09:17 AM 04-11-03 +1300, you wrote:
> >
> > Hi Dennis,
> >
> > As in a previous post I should have said FET EMULATION TOOL.
> > To avoid problems with my target board I set up the FET to do the
>switching
> > using a 1121A. When I had the regulator operating alone it was fine.
When
>I
> > try and switch power to it using the FET, I get these high currents.
> >
> >
> > all the best
> >
> >
> > Peter
> > >Hi Peter,
> > >You obviously have something terribly wrong as the regulator is
only
> > >designed to supply 25mA max.
> > >Drop the fet. don't need it as you can switch the enable pin
from a port
> > >directly. In shutdown mode this is only 0.1uA, with pin enabled
should be
> > >250uA. If your application requires low power consumption why not
try the
> > >TPS76933, this has higher shutdown current consumption 1uA but
lower only
> > >17uA quiescent current at full load, though this all depends what
your
>input
> > >voltage is as part is a fixed regulator only. Is your hardware
clean?
>flux
> > >residue etc.
> > >
> > >Dennis
> > >----- Original Message -----
> > >From: "Peter Grey" <martech@mart...>
> > >To: <msp430@msp4...>
> > >Sent: Monday, November 03, 2003 4:50 PM
> > >Subject: Re: [msp430] Problems with switching.
> > >
> > >
> > > > I use a MSP430F1121A and it is usually in  low current
applications. I
> > > > normally switch power to external chips only when I need
them to
>conserve
> > > > power. However, I now have a problem with this. I have a
regulator
> > > > (TPS60240) which I provide power to via P2.5. I found the
regulator
>was
> > > > drawing too much current in my circuit ( some 25mA with no
load on
>it.). I
> > > > set up the regulator by itself and it draws about 200uA with
no load
>and
> > >at
> > > > 3.0 volts which is about right. I then use the FET and
switch power to
>the
> > > > regulator. When it is not switched high, the current is
about 55uA and
> > >when
> > > > I switch it high it is 16.6mA! Again this is with no load.
The
>TPS60240
> > >has
> > > > 2 charge caps (1uF each) and an input and output cap (each
1uF).
> > > > Can anyone provide some clues as to what is happening?
> > > >
> > > >
> > > > Thanks
> > > >
> > > >
> > > > Peter
> > > >
> > > >
> > > >
> > > >
> > > > .
> > > >
> > > >
> > > >
> > > > ">http://docs.yahoo.com/info/terms/
> > > >
> > > >
> > > >
> > >
> > >
> > >
> > >
> > >.
> > >
> > >
> > >
> > >">http://docs.yahoo.com/info/terms/
> >
> >
> >
> >
> > .
> >
> >
> >
> > ">http://docs.yahoo.com/info/terms/
> >
> >
>
>
>
>
>.
>
>
>
>">http://docs.yahoo.com/info/terms/