Underwater ROV

Step 4 Navigation

To determine which direction the ROV is facing, I used an electronic compass. This is a Dinsmore 1490 electronic compass. I got it from Zargos Robotics. I used this schematic to create a visual representation of the direction. One note: This compass has no North. You just select a direction as north, and then all the rest will line up. It is also very sensitive to tilt, a few degrees and it gets screwed up. It senses changes in Earth's magnetic field, so make sure you place it far enough away from magnets, like the ones in the motors. If you need more info about the compass, check this site out

In the picture, the four wires in the silver casing will go to the surface and interface with the computer to show me which direction I am facing. I am writing a program that will rotate an image of the robot to show direction. However, this might take a while so for now I might just use the LEDs

For a tilt compensated compass, check out this one at Sparkfun. It is definitely top of the line, but also carries a huge price tag

EDIT:  I removed this because of its inability to maintain a steady heading.  This is most likely due to the tilt that the compass couldn't handle, along with the magnieting interference.

Comments

[pic16f630]

Very interesting. I wonder where did you get that electronic compass....

[Pyrotechnic-Robot]

alright so it is quite easy to make this compass.
FIrst you have to go to Zargos Robotics and get the compass sensor. it is located at their very bottom of the pagehttps://www.zagrosrobotics.com/Index.asp
then what I did is I made a little pcb board to fit the sensor and the lights and the output. I can give you the layout that I made if you would like it.
ŽPŽ
Just to tell you this compass is very finicky.

[SpaceShipOne]

I got it from a robotics website. It is a fairly standard compass used for navigation on robots. Its a Dinsmore 1490. A search online should yield several different stores that stock it