I'm interested in a project which given a GPS track or series of waypoints holds a heading. This project is similar to many of the auto pilot threads with some differences that may make it simpler.
I am hoping to use side scan sonar to map river bottoms on a smaller oar powered white water boat. Side scan sonar performs best when a relatively straight line is followed. Navigating down a river usually requires what's called ferrying to avoid obstacles. When ferrying down a river the boat's bow (or stern) doesn't always point in the direction of the river flow. Thus, if a transducer is attached to the boat it will be subject to a changing heading which will result poor sonar performance.
I'm wondering if I could follow a similar routine as the auto pilot but instead of changing the heading of the boat I'm thinking I can mount the transducer on a rotating mount and adjust it's heading to point downstream no matter the position of the boat. Alternatively, I could try installing a rudder on the pole and let the current guide the pole, but what's the fun in that.
I have a grasp of heading sensors and GPS, but I'm not as certain about changing the rotation of the pole so I'm wondering if others have tackled similar projects? Input is appreciated!