草图工作台中的草图验证工具

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This page is a translated version of the page Sketcher ValidateSketch and the translation is 22% complete.
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Sketcher ValidateSketch.svg Sketcher ValidateSketch

Menu location
Sketch → Validate sketch…
Workbenches
Sketcher, PartDesign
Default shortcut
None
Introduced in version
-
See also
Sketcher ConstrainCoincident, Topological naming problem

描述

草图验证(Validate sketch)工具可用于修复不可编辑的草图、存在无效约束的草图,以及添加有缺失的重合约束的根据DXF等文件中导入的几何图形所创建的草图。此工具也可有效的定位本地草图中缺失的重合约束,这个问题将导致在您试图运用一个PartDesign特征时生成一个"can't validate broken face"错误。

Sketcher ValidateSketch taskpanel.png

The Sketcher validation task panel

如何使用

  1. 选择待验证的草图,可以从模型树或通过单击3D视图中目标对象的一条边进行选择。请注意: 草图一定不能处于编辑模式中。如果您正处于草图编辑模式,需要退出草图编辑模式
  2. 从Sketch菜单或Part Design菜单中打开草图验证工具。
  3. 执行的具体操作请参考下列选项部分。
  4. 完成验证后点击Close按钮。

选项

缺失重合约束

找出有重合关系却缺失重合约束的顶点,并为之添加重合约束。按下Find按钮;程序会弹出一个对话框来报告找到了多少缺失的重合约束; 并在3D视图中以黄色小十字符号表示出来。按下OK来关闭此对话框,再按Fix按钮来添加缺失的重合约束。

如有需要,可在下拉字段中定义一个更大的公差值。

Press Highlight open vertexes to highlight vertexes that are outside this tolerance.

This tolerance is also used by the Find/Fix process.

通过选择"Ignore construction geometry"复选框在分析过程中忽略造型几何图形。

Invalid constraints

无效约束

For example, if there is a Circle-Line-Tangent constraint, but it references two lines, it is considered invalid.

(This sometimes happens due to the Topological naming problem, i.e. the external geometry changes type).

It also does other checks, such as for empty links.

Degenerated geometry

Degenerated geometry can result from solver actions in a sketch.

For instance, if a line is forced to shorten to become almost a point.

Other examples: a zero length line or zero radius circle/arc.

Reversed external geometry

逆向外部几何图形

This process might be helpful if sketches with external-geometry fail to solve because of these changes.

Constraint orientation locking

约束方向锁定

Internally they work by constraining the angle between tangent vectors. With tangent constraint for example, the angle can be 0 or 180 degrees (co-directed or opposed vectors). The actual angle is remembered in the constraint data ("constraint orientation is locked"), it guards against flipping. But the angle can be erased ("constraint orientation unlock") or updated; these tools do exactly that.

The locking mechanism typically works well and this tool should not be needed. It should only used after making a backup of the open document.