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Will an IMU tell me how far my robot has moved?

Topic last updated 13 Mar 2012, by Adam Green. 2 replies
Gregory Martin
13 Mar 2012

Hi I want to know where my tracked vehicle is. It has a wifly module and I'm wondering if the data I get from this 6 degrees IMU will enable me to know how far my vehicle has moved and in what direction. http://www.ebay.co.uk/itm/260946284718?ssPageName=STRK:MESINDXX:IT&_trksid=p3984.m1436.l2649. If this is not the right sort of device can anyone suggest a better type. Im hoping to do a simple dead reckoning navigation.

Sjoerd Brandsma
13 Mar 2012

Hi,

IMU's are not the best way to do this. They can tell you rotation, acceleration and forces like that.

To do cheap distance measurements you can do something like this: http://www.martijnthe.nl/2009/07/interfacing-an-optical-mouse-sensor-to-your-arduino/

Regards, Sjoerd

Adam Green
13 Mar 2012

Wheel encoders will probably work better than an IMU in telling you how far you have moved but an IMU which has gyros and magnetometers can work quite well for the production of a heading measurement. I find the following article by David Anderson to be a great overview of such sensor fusion: http://www.geology.smu.edu/dpa-www/robo/Encoder/imu_odo/

-Adam