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XBee compass interference


#1

I was thinking about getting a pair of 60mW XBEee’s for RWAR, but I am a little worried about them interfering with the IMU/compass.

Anyone have any thoughts? Should I go with the 1mW ones to avoid this sort of situation? Of course, I would locate the XBee as far from the compass as possible, but I’m not sure if I can get it more than 6-8 inches away from the IMU.


#2

I would say they will not interference with each other. I am not sure though. So I checked out some google pages and came across this website

Check out this comment:

[quote]Comment by Radoslaw Kornicki on January 24, 2010 at 1:25pm
I had no issues with none of my sensor readings when using xBee. Actually I’ve used it in such configuration from very beinging, I’ve never even hooked up this board directly to the PC serial port.
I also had no problems with getting a propper GPS lock. Of course the xBee on the picture is just for tests - final version will use different module with a wire antenna.
I think in the end the trick is that I have separated the sensor circuit (analog) portion from the digital one, they have separate voltage regulators and signal tracks are placed as far apart as possible on the board (I also use a 4 layer board - this way I could ground planes to isolate possible noise). In the early tests I had lots of noise comming from the PWM inputs and the servos themselves - optical isolation did a great job dealing with that noise.
As to the mounting in the plane - I have nice spot in the wing of the plane - no interference with cables and etc.[/quote]

Note that he has used separated power supplies, separate circuits and the signal lines are as far away as possible.

I am not sure if this will help you, but it might give you some tips though.

I do not have a compass otherwise I would try it out for you. (I own the 60mw xbees)

Note: you can also configure the 60mw xbees to send a less stronger signal.


#3

I have a XBee 60mW pretty close to my compass. All powered from the same source and I haven’t had any problems.


#4

Thanks Geir, that’s exactly the response I was looking for :slight_smile:


#5

Can I know what is over at the prototyping area of your shield, Geir?


#6

Not much really.
The headers are for signals to the rudder servo, motor PWM and winch system. There is also a transistor for pulling up the voltage to the MOSFET for the motor.


#7

How much range do you get with the XBee out on open water?


#8

Geir, do you have a project page for you vehicle? I guess “vessel” would be the correct term instead of “vehicle”.

I stopped being a lazy and found it myself: http://letsmakerobots.com/node/22108 :stuck_out_tongue:


#9

Chris: I haven’t had a chance to test it yet and with the winter coming I probably wont get to test it before next spring. The spec says 1500m and you wont get more line of sight then open water :slight_smile: But as its mounted inside the plastic box i’m hoping for 8-900m. If not I will change it to an external antenna.

mhectorgato: So you found it at LMR :slight_smile: It’s also here (link removed) with some software download if you are interested.