1. Robotics & Sensor Fusion for Mechatronics Autonomous vehicle navigation An Obstacle Avoidance Exercise Luca Baglivo, Mariolino De Cecco

2. Robotics & Sensor Fusion for Mechatronics We’re using two-dimensional grids: maps represented as images!

3. Robotics & Sensor Fusion for Mechatronics From CAD to Image

4. Robotics & Sensor Fusion for Mechatronics ATTRACTIVE POTENTIAL REPULSIVE POTENTIAL + IMAGINE ROBOT AS A BALL ROLLING DOWN HILLS

5. Robotics & Sensor Fusion for Mechatronics TOTAL POTENTIAL

6. Robotics & Sensor Fusion for Mechatronics THE RESULTING FORCE IS THE GRADIENT AND GIVES DIRECTION TO THE ROBOT This example is in the Matlab script “OstacoliQuadrati.m”

7. Robotics & Sensor Fusion for Mechatronics POTENTIAL FIELDS METHOD FEATURES: AUTOMATIC PATH PLANNING FOR OBSTACLE AVOIDANCE IS BOTH A PLANNING & CONTROL STRATEGY ALL-IN-ONE BEST FOR LOCAL PATH PLANNING->UNEXPECTED OBSTACLES BE AWARE FROM LOCAL MINIMA! HARMONIC POTENTIAL FUNCTIONS HAS PROVEN ONLY GLOBAL MINIMA NOT SUITABLE FOR HIGH PRECISION POSITIONING ON TARGET

8. Robotics & Sensor Fusion for Mechatronics A FORMULATION

9. Robotics & Sensor Fusion for Mechatronics A FORMULATION

10. Robotics & Sensor Fusion for Mechatronics A FORMULATION

11. Robotics & Sensor Fusion for Mechatronics A FORMULATION

12. Robotics & Sensor Fusion for Mechatronics A FORMULATION

13. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORIDOR ALIGNMENT FOR LINE FOLLOWING The attractive potential can be defined punctually as desired. Build a vector field that point towards desired path.

14. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORRIDOR ALIGNMENT FOR LINE FOLLOWING How to define it LcLc xFxF yFyF K y angles (+) alpha K

15. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORIDOR ALIGNMENT FOR LINE FOLLOWING How to compute steering angle input K y alpha K delta steering axis

16. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORIDOR ALIGNMENT FOR LINE FOLLOWING Now add the repulsive force vector F rep, and play … K y F rep F tot delta’

17. Robotics & Sensor Fusion for Mechatronics OBJECT PICKING A possible application for forklifts

18. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORIDOR ALIGNMENT FOR LINE FOLLOWING Try with: Tricycle robot forward velocity, point obstacle at (x F,y F ) = (4,1.5) yRyR b D1

19. Robotics & Sensor Fusion for Mechatronics ANOTHER, NAIVE FORMULATION A VIRTUAL CORIDOR ALIGNMENT FOR LINE FOLLOWING A control sketch Robot kinematic model Steer control velocity steer angle Potential field gradient vector y + - alpha K delta k control

20. Robotics & Sensor Fusion for Mechatronics Bibliography 1.Siegwart R., Nourbakhsh I, Scaramuzza D., Introduction to Autonomous Mobile Robots