Someone who see Roktrack in action for the first time say, "If there are no pylons, where would it go?".

However, this does not happen. If there is no pylon, it simply turns 360 degrees on the spot and stops because it cannot find the pylon. If you look at mowing through a polygon that is vertexed with pylons, you will see that the pylons are used to define the boundaries. But in fact, Roktrack uses pylons not so much to define boundaries, but rather as guideposts to point the way to where it should go.

Basically, Roktrack heads toward the pylon it see, and when it gets a certain degree closer, it turns around and find the next pylon, and continue in the same manner. By gradually shortening this approach, it moves inward and fills the polygon. Since the principle of operation is simply to approach a visible pylon, it is impossible for Roktrack to go in the wrong direction unless it is misdetected. Personally, I find this more reassuring than GPS guidance because the working area is visually visible.

Drive Route

Flow Chart

*The complete flowchart is uploaded as a pdf file.

Encoderless

Pylons as signposts pointing the way make the drive motors encoderless. As shown in the image below, it is possible to calculate the deviation of the recognized pylon from the center of the image. In this case, there is a 20px gap to the right of where the center of the screen should be (the position of the recognized pylon). In this case, Roktrack will increase the PWM of the right motor and decrease the PWM of the left motor. The same calculation is performed during the next process, and if there is a gap, it is compensated. In this way, straightness is gradually ensured.

It is not where you are, but whether you can see your way.