Grasp It!

Task

Implement find_the_ball() and grasp() functions in exercise_5.py that will find and grasp the ball. The function are methods of a class Grasper, that contains several useful methods. After grasp, you should move the ball up such that it is at least 5cm above the table.

The class takes two arguments

• client - instance of pyCub class that controls the simulation

• eye - name of the eye in which the camera is placed; ‘l_eye’ or ‘r_eye’ The two function have predefined arguments and returns:

• find_the_ball() - takes no arguments and should return (u, v) - center of the ball in image plane

• grasp() - takes one argument center (the 2D center returned by find_the_ball()) and should return 0 in case of successful grasp You are free to add any method or variable to the class, but only find_the_ball() and grasp() will be called.

The class Grasper contains several helpful methods, e.g., to get RGB and Depth image; to deproject the 2D point; to close fingers.

The ball is always green (0, 255, 0) and it’s radius is 2.5cm.

Scoring

• If the ball is 5cm above the table and in the hand of the robot after you return from grasp(), you passed the test

Requirements

Those apply mainly for exercise_5_tester.py to work correctly:

• do not create new client instance, use the one that is passed as an argument to Grasper class

• do not rename the functions find_the_ball(), grasp() or the file

• The ball must be 5cm above the table and in the hand of the robot after grasp() returns

Those apply so that you fulfill the exercise as intended:

• Do not turn of gravity