Archives for: November 2004

Continuing on, on my Mobile Robotics assignment, in the current lab we use simple path planning techniques to get from point A to point B.

Using a map built by exploring a world (as mentioned in the previous article) the code plans a path (not necessarily optimal) from the starting position to the goal position.

The "wavefront" path planning algorithm is simple, but quite effective. It is able to find a path through free space, avoiding obstacles and all locations not explored as yet.

Notice how the path planned "hugs" the wall. This is a consequence of the simplicity of the path planning algorithm and will cause undesired (duh!) collision with obstacles. We can however get over this problem very easily by "growing" the obstacles by the size of the robot.

In the following images, the obstacles are "grown" by a few cells (the areas marked in light pink) before planning is done. This guarantees a safe path that the robot can take.

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