Photoswitches vs. Camera

[Geek 2.0]

Here's an interesting idea: if you aren't going to use your camera for anything else, you could use it as a line tracker. In my opinion, it would seem easier to use for a two-axis drivetrain (such as mecanum or crab or whatnot) because it would give you direction to a line, so that you can strafe along it as opposed to trying to follow it. What do you think?

[DavidGitz]

Originally Posted by Geek 2.0

Here's an interesting idea: if you aren't going to use your camera for anything else, you could use it as a line tracker. In my opinion, it would seem easier to use for a two-axis drivetrain (such as mecanum or crab or whatnot) because it would give you direction to a line, so that you can strafe along it as opposed to trying to follow it. What do you think?

We had originally looked at doing this. There are advantages and disadvantages of using a camera for line-tracking.
Advantages:
-More accurate (assuming a good vision processing algorithm)
-Identify path options easier: branch, end, etc.
-History: You can look at the angle of the line along with your position to determine the appropriate heading.
Disadvantages:
-Development time: Develop a vision processing algorithm that works reliably, efficiently and handles the different path options will take longer than using the KOP line sensors
-Lag: The line sensors are read faster than the camera. With very basic image processing we were at about 12 fps with the camera, compared to the line sensors running as fast as the periodic tasks while loop they are in are called.

I personally thought the disadvantages outweighed the advantages, and compared to the relative ease we had with the line sensors (we were line tracking within about 2 hours once we started installing them) and the lack of being able to use the camera for anything else (we weren't planning on putting it on a pan/tilt mount) it was an easy choice.