Just a thought, but make sure that /dev/ttyUSB0 is actually the razor.
I'd be careful doing a symlink from USB0 to /dev/imu unless you really
only have a single usb serial device in your system.  I have 3 on my
robot, so I just created some udev scripts like shown on the hokyo
tutorial:

http://www.ros.org/wiki/hokuyo_node#Using_udev_to_Give_Hokuyos_Consistent_Device_Names

On Sat, Mar 12, 2011 at 10:03 AM, Patrick Goebel <patrick@pirobot.org> wrote:
> Hi Adam,
>
> Thanks for making this wrapper available.   I have a Sparkfun 9d_razor and I
> have upgraded the firmware using the .pde files in
> imu_9drazor/src/SF9DOF_AHRS.  I did this under Windows using the Arduino IDE
> (version 0022) and the upload proceeded without errors.
>
> Back on Linux with the IMU on port /dev/ttyUSB0 I followed the Wiki
> instructions:
>
> $ sudo ln -s /dev/ttyUSB0 /dev/imu
> $ roslaunch imu_9drazor imu.launch
>
> The launch proceeded without errors with the output:
> process[imu_node-1]: started with pid [23276]
> process[imu_msg_converter-2]: started with pid [23277]
>
> However, when I echo the imu topic with "rostopic echo imu" there is no data
> being published. Ditto for the topic imu/imu_raw.  Both topics are listed
> with "rostopic list".
>
> One silly question: aside from having the IMU connected to the USB port, do
> I also have to apply power to the white power connector?  I did not have to
> do this under Windows to see data via the firmware test application.
>
> Any thoughts?
>
> Thanks!
> Patrick Goebel
> http://www.pirobot.org
>
>
> On 01/10/2011 09:06 PM, Adam Stambler wrote:
>
> Hi,
>
> Just an IMU won't be able to track the position of the IMU over time.  It
> can be combined with odometry measurements with a kalman filter to a decent
> estimate though.
>
> If you are looking for a sparkfun IMU with a premade ros-wrapper, I have a
> wrapper for the sparkfun 9d razor imu called imu_9drazor.  It is a part of
> the rutgers-ros-pkg.
>
> Regards,
> Adam
>
> On Mon, Jan 10, 2011 at 11:58 PM, abhy <abhy.12354@gmail.com> wrote:
>>
>> hello,
>>
>> Does ROS have Sparkfun IMU supporting driver?
>>
>> "http://www.robotshop.com/sfe-atomic-imu-6-degrees-of-freedom-xbee-ready-1.html"
>>
>> Is this IMU sufficient for giving X, Y, Z coordinates of the Robot?
>>
>> Thanks,
>> Abhy
>> --
>> View this message in context:
>> http://ros-users.122217.n3.nabble.com/ROS-driver-supporting-Sparkfun-IMU-tp2232681p2232681.html
>> Sent from the ROS-Users mailing list archive at Nabble.com.
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>
>
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