Turtlebot3, change the velocity (linear and rotational) of the robot while driving depending on the traveled distance(angle)

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hello all, I would have a changeable velocity to drive the robot instead of the fixed one. I mean at the beginning of the movement I want the velocity to be low and then by increasing the traveled distance ethe velocity should increase until reaching the maximum value, then before reaching the goal, I want the velocity to start to decrease until '0' when arriving the goal. Any idea from you could help Thanks in advance