a,
Case I: 500mm
CaseII: 125mm


fruit

01----------------

 \






Camera Optical Center, 0O
 /
 /
 /.


 fruit

 /
 /

 /
 / 162 mm

/




 %\ 8mm

 \ Infinite Image Plane


Case I: 1077 pixels
Case II: 269 pixels


Figure 7.6. Relationship between the amplitude of a fruit and the amplitude of its image on
 the camera image plane.


 To provide more information for determining the performance requirements for the

vision control system, the difference between the location of the targeted fruit and the end-

effector was calculated. First, the previously observed motion of a fruit was expressed as a

vector,

 fm = af sin(ot)

where fm = fruit motion (pixels),

 at = fruit motion amplitude (pixels),

 o = frequency of fruit motion (deg/sec), and

 t time (sec).

The predicted motion of the robot's end-effector was also described as a vector,

 rm = ar sin(ct+o)

where rm = end-effector motion (pixels),

 ar = end-effector motion amplitude (pixels), and

 phase lag between fruit and end-effector motion (deg).


I


I