Speed planning guidance line for mild slow down

A non-transitory machine-readable medium having instructions stored therein, which when executed by a processor, cause the processor to perform operations of operating an autonomous driving vehicle (ADV), the operations comprising:

• in response to a request for driving in a natural deceleration mode, determining a current speed of the ADV;
• generating a speed guideline based on a predetermined natural deceleration profile associated with the ADV in view of the current speed of the ADV;
• performing a speed planning operation by optimizing a total cost function based on the speed guideline to determine speeds of a plurality of trajectory points along a trajectory planned to drive the ADV;
• and
• generating a plurality of control commands based on the speed planning operation to control the ADV with the planned speeds along the trajectory, such that the ADV naturally slows down according to the predetermined natural deceleration profile.

A data processing system, comprising:

• a processor;
• and
• a memory coupled to the processor to store instructions, which when executed by the processor, cause the processor to perform operations of operating an autonomous driving vehicle (ADV), the operations including
• in response to a request for driving in a natural deceleration mode, determining a current speed of the ADV,
• generating a speed guideline based on a predetermined natural deceleration profile associated with the ADV in view of the current speed of the ADV,
• performing a speed planning operation by optimizing a total cost function based on the speed guideline to determine speeds of a plurality of trajectory points along a trajectory planned to drive the ADV, and
• generating a plurality of control commands based on the speed planning operation to control the ADV with the planned speeds along the trajectory, such that the ADV naturally slows down according to the predetermined natural deceleration profile.