Motor-vehicle trajectory planning and control to cause automated motor-vehicles to perform low-speed manoeuvres in automated driving

1. An automotive electronic dynamics control system for a motor-vehicle equipped with and automotive automated driving system designed to cause the motor-vehicle to perform low-speed manoeuvres in automated driving;

the automotive automated driving system comprises:

an automotive sensory system designed to sense motor-vehicle-related quantities, and

automotive actuators comprising an Electric Power Steering, a Braking System, and a Powertrain;

the electronic dynamics control system is designed to implement:

a Driving Path Planner designed to:

receive data representative of static obstacles in the surroundings of the motor-vehicle and representing static space constraints to the motion of the motor-vehicle, and

compute, based on the received data, a planned driving path for the motor-vehicle during a low-speed manoeuvre performed in automated driving;

a Model Predictive Control (MPC)-based Trajectory Planner and Controller designed to:

receive from the Driving Path Planner data representative of the planned driving path and from the automotive sensory system data representative of positions and orientations of the motor-vehicle and of dynamic obstacles in the surroundings of the motor-vehicle and representing dynamic space constraints to the motion of the motor-vehicle, and

compute, based on the received data, a planned lateral trajectory and a planned longitudinal trajectory for the motor-vehicle during the low-speed manoeuvre performed in automated driving; and

a Motion Controller designed to:

receive from the Trajectory Planner and Controller data representative of the planned lateral and longitudinal trajectories, and

compute commands for the Electric Power Steering based on the planned lateral trajectory, and for the Braking System and the Powertrain based on the planned longitudinal trajectory;

the Driving Path Planner is designed to compute the planned driving path as an obstacle-free driving corridor within which the motor-vehicle may be driven and made up of a series of driving path segments each with a length and an orientation referenced in an inertial reference frame;

the MPC-based Trajectory Planner and Controller comprises:

an MPC-based Lateral Trajectory Planner and Controller designed to compute the planned lateral trajectory as a series of steering requests (6) referenced in a motor-vehicle reference frame; and

an MPC-based Longitudinal Trajectory Planner and Controller designed to compute the planned longitudinal trajectory as a series of longitudinal acceleration requests;

the Lateral Trajectory Planner and Controller is further designed to compute the planned lateral trajectory based on a linearized Model which exhibits a representation singularity whenever the relative orientation of a couple of successive driving path segments of the planned driving path is equal to or higher than a given amount;

the Lateral Trajectory Planner and Controller is further designed to dynamically modify relative orientation (θ ROT ) of the motor-vehicle reference frame and the inertial reference frame along the planned driving path so as to result in the relative orientations of all of the couples of successive driving path segments of the planned driving path being lower than the given amount.

2. The automotive electronic dynamics control system of claim 1 , wherein the Lateral Trajectory Planner and Controller is further designed to compute the orientation (θ ROT ) of the motor-vehicle reference frame relative to the inertial reference frame based on the orientation (θ i ) of the driving path segment currently driven by the motor-vehicle and on the orientation (θ i+1 ) of the next driving path segment.

3. The automotive electronic dynamics control system of claim 2 , wherein the Lateral Trajectory Planner and Controller is further designed to compute the orientation (θ ROT ) of the motor-vehicle reference frame relative to the inertial reference frame also based on the orientation (θ i+2 ) of the second next driving path segment.

4. The automotive electronic dynamics control system of claim 3 , wherein the Lateral Trajectory Planner and Controller is further designed to compute the relative orientation of the motor-vehicle reference frame and the inertial reference frame as a linear interpolation of the orientation (θ i ) of the driving path segment currently driven by the motor-vehicle and of the orientations (θ i+1 , θ i+2 ) of the first and next driving path segments.

5. The automotive electronic dynamics control system of claim 4 , wherein the Lateral Trajectory Planner and Controller is further designed to compute the relative orientation of the motor-vehicle reference frame and the inertial reference frame as:

θ

ROT

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(

θ

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θ

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d

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(

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(

26

)

where:

θ ROT is the orientation of the motor-vehicle reference frame relative to the inertial reference frame,

θ i , θ i+1 , θ i+2 are the orientations of the driving path segment currently driven by the motor-vehicle, of the first next driving path segment, and of the second next driving path segment in the inertial reference frame,

W is a weighting factor,

x v ,y v are the current motor-vehicle's coordinates in the inertial reference frame,

d is the Euclidean distance between the current position of the motor-vehicle 2 and the end of the driving path segment containing the current position of the motor-vehicle 2 , and

d i+1,i is the length of the next driving path segment to the one containing the current position of the motor-vehicle 2 .

6. An automotive electronic control unit designed to implement the automotive electronic dynamics control system as claimed in claim 1 .

7. Software loadable in an automotive electronic control unit and designed to cause, when executed, the automotive electronic control unit to become configured to implement the automotive electronic dynamics control system as claimed in claim 1 .