Shape Pattern of Kaff
The plots below show the linear relationship between
Kaff and the Position Error of a commanded move.
NOTE: All peak error measurements were made during
the first half of the move for comparison purposes.
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 0
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 188 counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 20,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 154 counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 70,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 72 counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 100,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 28 counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 120,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 16
counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 170,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 98
counts
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10,000 count move
Trapezoidal move:
5e5 accel, decel, vel |
Green - Commanded Velocity
Yellow - Commanded Acceleration
White - Position Error |
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Kaff = 200,000
Kp = 100
Ki = 0
Kd = 2,000
Peak Position Error
= 150 counts
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To emphasize the linear relationship between Kaff and
Position Error, the grpah below summarizes the data from the above plots.
There is some non-linearity near the zero position error because of the
unsophisticated manner in which position error is determined.
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