Mitsubishi Electric CR750 Series, Instruction Manual

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Appendix-618 Spline interpolation
7Appendix
7.3.3 Explanation of functions
(1) Path adjustment
The spline curve’s shape can be compensated by using the path adjustment function. "Tolerance designa-
tion", "arc designation", "spline cancel" and "block length ratio" are available for compensating the path.
■ Tolerance designation
Designate the tolerance
*1)
to adjust the degree of spline curve swelling in block units. The setting range is 0
to 100%, and the default value is 100% (No adjustment). The smaller the setting value is, the smaller the
degree of curve swelling is. When 0% is set, the target block will be linear.
The tolerance can also be designated for the posture. The smaller the setting value is, the smaller the
degree of swelling in posture change is. However, the smoothness in posture change will drop when pass-
ing through the path points.
Fig.7-13:Tolerance
■ Arc designation
Arc designation method is different depending on the version of the spline file.
1) Spline file version 02
When two consecutive blocks are designated as an arc (arc designation at start point of a block), the
curve that consist of those two blocks will be an arc instead of a spline. If this is applied at a section
requiring an arc-shaped curve, such as at a corner, an accurate arc can be drawn with fewer path points
than the spline curve.
Fig.7-14:Arc designation (Spline file version 02)
*1) Tolerance typically refers to the tolerable error and accuracy. However, in this function it refers to
the degree of spline curve swelling in respect to the lines (segments) that connect the path points.
トレランス
100%（調整なし）
60%
30%
0%（直線）
Tolerance
100% (no adjustment)
0% (linear)
Blocks subject to tolerance
The tolerance is set as the path point data. The tolerance set for the path point on the start position side
of each block is reflected onto that block. In the following example, the tolerance set for the path point n
is applied on block n.
経路点n
経路点n+1
ブロックn
動作方向
Path point n+1
Block n
Path point n
Direction of
movement
Arc designation
These 2 blocks are des-
ignated as arc