Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: Excalib12e on November 09, 2010, 10:18:06 AM

Title: IMU sensor for camera position
Post by: Excalib12e on November 09, 2010, 10:18:06 AM
Hello,

I am building a spherical rolling robot. powered by a pendulum mechanism. The difficult part is that I have to implement a camera onto this mechanism of which the angle ranges from 0 - 90 degrees. The camera has to point in always the same direction. I am thinking of coupling it to a servo, arduino and a IMU so that the camera is always kept at the same angle with respect to the ground.
It will only need to operate in one axis in this case.

Can anyone advise if this would be the right way to go? With an IMU that is. 
Title: Re: IMU sensor for camera position
Post by: Metal Slug 2 on November 09, 2010, 11:01:21 PM
If what I'm guessing is correct, then the camera only needs to be able to rotate on a horizontal axis +/-45 degrees from its initial position.  If this is the case, then I would recommend not using an IMU as they are rather expensive ($50+).  Instead, for what you want to do, I would recommend a digital compass (http://www.sparkfun.com/commerce/product_info.php?products_id=7915).

The compass will allow you to always orient your camera in a specific direction (if you so choose), so when you turn it on, it will always try to point for example North.  You could also just read the initial position of the compass, and compare the cameras deviation from that position and readjust accordingly with the servo you mentioned you would have the camera mounted on.  The digital compass would also be easier to use.
Title: Re: IMU sensor for camera position
Post by: Razor Concepts on November 10, 2010, 05:04:06 AM
If you want to skip the programming, buy a RC helicopter gyro with heading hold.
Title: Re: IMU sensor for camera position
Post by: azy on November 13, 2010, 06:39:13 AM
cnat you mount it on some kind of weighted spindle setup....gravity alway keeping it level ?