CN104537191A - Drawing method for three-dimensional rebar model schematic diagram - Google Patents

Abstract

The invention relates to a drawing method for a three-dimensional rebar model schematic diagram, and aims to provide the drawing method for the three-dimensional rebar model schematic diagram. The drawing method is capable of drawing a random shaped three-dimensional rebar model schematic diagram. According to the technical scheme of the drawing method, the drawing method for the three-dimensional rebar model schematic diagram comprises the following steps: A, extracting rebar model information used for reading engineering properties and space geometrical information of a three-dimensional rebar model, and the space geometrical information of the model comprises piecewise numbers and piecewise geometrical properties of the model; B, converting geometric data, and the original three-dimensional geometric data is converted into two-dimensional or one-dimensional geometric data which can be easily demonstrated on a blueprint through coordination transformation and coordination rotation; C, correcting the geometric data, and sequentially carrying out the overall scaling and the piecewise adjustment on a converted two-dimensional or one-dimensional geometric data; D, drawing a rebar schematic diagram, carrying out the drawing of the rebar schematic diagram on each group, and the drawing of the rebar schematic diagram for each group comprises two parts, namely rebar schematic lines and information labels.

Description

A kind of method for drafting of three-dimensional reinforcing bar model schematic

Technical field

The present invention relates to Computer-aided Design Technology, three-dimensional information modelling technique and three-dimensional one-tenth diagram technology, especially a kind of method for drafting of three-dimensional reinforcing bar model schematic.Be applicable to the civil engineering work industry needing the adopted three-dimensional design using reinforced concrete structure, comprise water resources and hydropower construction, work China Democratic National Construction Association, road and bridge, also comprise the industries such as power plant construction, port construction, blower foundation.

Background technology

Current, along with the application of computer technology in water resources and hydropower construction industry is more and more extensive, the concept of three-dimensional design is also more and more mentioned.Factory building in power station is based on xoncrete structure, the professional leading specialty of factory building (structure), a general medium-sized project factory part drawing amount is at about 1000, factory building (structure) specialty nearly 500 multiple, about accounting for half, wherein in the majority with reinforcement drawing again, at about 300, account for 1/3 of whole engineering drawing total amount.Traditional method for designing is that the space imagining ability relying on oneself in D CAD carries out Reinforcement Design, manually draws, by Microsoft Excel statistics reinforcing bar amount, when school is examined, personnel need the reinforcing bar drawing according to drawing that whole reinforcing bar amount is recalculated one time, workload is abnormal huge, be difficult to the reinforcement drawing need of production meeting actual factory building specialty, therefore, three-dimensional arrangement of reinforcement technology has just been born under this demand, have benefited from the develop rapidly of computer software and hardware and going deep into of three-dimensional design research and apply, be also applied in engineering by real gradually.

The prerequisite of three-dimensional arrangement of reinforcement Technology application to have three-dimensional entity's structure model, and then use computer technology, under the requirement of design specifications, in conjunction with the arrangement of reinforcement parameter that designer or Reinforcing Steel Bar Calculation software provide, comprise the grade of reinforcing bar, diameter, spacing and other arrangement requirement, in 3D solid structural model, directly generate the method for designing of three-dimensional rebar model.After the rebar model of three-dimensional generates, can directly count bar list and material list, and can be extracted out the reinforcement drawing of arbitrary cross-section by the mode of cutting figure.

In bar list, need the schematic diagram of the reinforcing bar that each form is provided, the current method had is the schematic diagram that method by enumerating pre-defines often kind of pattern reinforcing bar, when extracting three-dimensional reinforcing bar schematic diagram, is mated by three-dimensional reinforcing bar with the pattern defined.But due to the complicacy of reinforcing bar true in large volume model, this method workload is too large and can not enumerate all patterns in advance.

Summary of the invention

The technical problem to be solved in the present invention is: for above-mentioned Problems existing, provides a kind of method for drafting of three-dimensional reinforcing bar model schematic, to draw the three-dimensional reinforcing bar model schematic of arbitrary shape.

The technical solution adopted in the present invention is: a kind of method for drafting of three-dimensional reinforcing bar model schematic, is characterized in that step is as follows:

A, rebar model information extraction, for reading engineering attribute and the space geometry information of three-dimensional rebar model, the space geometry information of model comprises number of fragments and the segmentation geometric attribute of model, segmentation geometric attribute refers to the type of segmentation, physical dimension and controling parameters, and Segment type comprises line segment, circular arc, elliptic arc and SPL;

B, geometric data convert, and the geometric data of former three-dimensional is converted to the easier two dimension expressed on drawing or one dimension geometric data by coordinate translation conversion and Rotating Transition of Coordinate;

C, geometric data correction, carry out overall convergent-divergent and segmentation adjustment successively to the two dimension after conversion or one dimension geometric data;

Overall convergent-divergent, the two dimension of three-dimensional rebar model or one dimension geometric data entirety are zoomed to pre-sizing, and in overall convergent-divergent process, the ratio of each section of model remains unchanged;

Segmentation adjusts, separately convergent-divergent adjustment is carried out to each segmentation, too small segmentation schematic lines is amplified to be easy to identification line segment type and mark line segment size, and long segmentation schematic lines is contracted to be easy to the typesetting of reinforcing bar schematic diagram in bar list and overall appearance;

D, drafting reinforcing bar schematic diagram, carry out the drafting of each group reinforcing bar schematic diagram, each group reinforcing bar schematic diagram is drawn and is comprised reinforcing bar schematic lines and information labeling two parts, wherein reinforcing bar schematic lines is two dimension or the one dimension geometric data of step C gained, and information labeling is the engineering attribute of three-dimensional rebar model and the physical dimension of model segment in steps A;

By reinforcing bar schematic lines and information labeling typing respective cells, obtain reinforcing bar form.

The overall convergent-divergent of described step C, first obtains the area size at two dimension or place, one dimension geometric data all reference mark, then the size in this region and target area size is contrasted, obtain a scale factor, by the reference mark that this scale factor convergent-divergent is all; Described target area size is the cell size of placing reinforcing bar schematic diagram in reinforcing bar form.

Described step C segmentation adjustment, obtain the length of each segmentation and the limit value I of setting and limit value II contrast, limit value II is greater than limit value I, and section length is less than adjusting according to the scale factor of itself and limit value I of limit value I, is greater than limit value I to its length; Section length is greater than adjusting according to the scale factor of itself and limit value II of limit value II, is less than limit value II to its length.

The invention has the beneficial effects as follows: the present invention enables computing machine be the schematic diagram of two dimension by the three-dimensional reinforcing bar model conversation of the arbitrary shape be distributed in solid model space adopting three-dimensional design to be formed, and then form a form or drawing, and by overall convergent-divergent and segmentation adjustment, the Model Results of three-dimensional design is converted to final drawing, solve the problem that three-dimensional design is combined with actual production.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of method of the present invention.

Fig. 2 is the geological information interrecord structure of one group of reinforcing bar pattern.

Fig. 3 is that certain hydroelectric project unit spiral case layer and following peripheral rebar model are shown.

Fig. 4 is three-dimensional reinforcing bar model display in embodiment one.

Fig. 5 is segmentation convergent-divergent adjustment process in embodiment one.

Fig. 6 is that the reinforcing bar schematic diagram generated in embodiment one is shown.

Fig. 7 is three-dimensional reinforcing bar model display in embodiment two.

Fig. 8 is that the reinforcing bar schematic diagram generated in embodiment two is shown.

Fig. 9 is that the part reinforcing bar form that certain hydroelectric project unit spiral case layer and following peripheral rebar model extract is shown.

Embodiment

Adopt three-dimensional arrangement of reinforcement technology to generate in certain hydroelectric project unit spiral case layer and following peripheral rebar model and contain nearly ten thousand large volume reinforcing bars, reinforcing bar pattern hundreds of, as shown in Figure 3.Need the schematic diagram extracting this hundreds of reinforcing bar pattern when generating reinforcing bar form, this example chooses two kinds of typical-samples, comes by reference to the accompanying drawings to be described in detail to technical solution of the present invention.

As shown in Figure 1, technical solution of the present invention comprises rebar model information extraction, geometric data conversion, geometric data correction, draws reinforcing bar schematic diagram four main process.

A, rebar model information extraction, for reading engineering attribute and the space geometry information of three-dimensional rebar model.Described engineering attribute refers to the attribute relevant to engineering that engineering significance representated by three-dimensional model and model itself are designed personnel and give.The space geometry information of model comprises number of fragments and the segmentation geometric attribute of model, segmentation geometric attribute refers to the type of segmentation, physical dimension and controling parameters, type comprises line segment, circular arc, elliptic arc and SPL, and the content of the geometric attribute of different Segment type is also different: 1. the geometric attribute of straight-line segment comprises line segment length, two-end-point coordinate and normal vector; 2. the geometric attribute of arc section comprises centre point coordinate, radius, arc length, central angle, normal vector, circular arc start angle and circular arc termination point; 3. the geometric attribute of oval segmental arc comprises focal coordinates, long axis length, minor axis length, central angle and arc length, normal vector, start angle and termination point; 4. the geometric attribute of SPL is endpoint curve coordinate, length of curve, multiple point coordinate along curve distribution.

B, geometric data convert, the geometric data of former three-dimensional is converted to the easier two dimension expressed on drawing or one dimension geometric data, comprise coordinate translation conversion and Rotating Transition of Coordinate two parts: 1. described coordinate translation converts and refers to that the transformation matrix of this process is the translation matrix of 3 X 1 by the coordinate translation at the rebar model reference mark of optional position in three dimensions near drawing coordinate initial point; 2. described Rotating Transition of Coordinate refers to a reference mark on three-dimensional rebar model for reference point, and by rotating to an angle, by three dimensions, rebar model data rotation is on drawing plane at any angle, and the transformation matrix of this process is the rotation matrix of 3 X 3.

C, geometric data correction, revise the two dimension after conversion or one dimension geometric data, comprise overall convergent-divergent and segmentation adjusts two parts.1. described overall convergent-divergent, be according to reinforcing bar schematic diagram width requirement, the geometric data entirety of three-dimensional rebar model is zoomed to pre-sizing, in overall convergent-divergent process, the ratio of each section of model remains unchanged; 2. described segmentation adjustment, according to the standardization of reinforcing bar schematic diagram and cosmetic requirements, separately convergent-divergent adjustment is carried out to the segmentation schematic lines do not met the demands, be easy to identification line segment type and mark line segment size after too small segmentation schematic lines is amplified, and after long segmentation schematic lines is reduced, be easy to the typesetting of reinforcing bar schematic diagram in bar list and overall appearance.

D, drafting reinforcing bar schematic diagram, require according to bar list typesetting the drafting carrying out each group reinforcing bar schematic diagram, and each group reinforcing bar schematic diagram is drawn and comprised reinforcing bar schematic lines and information labeling two parts.1. described reinforcing bar schematic lines, is the two dimension after the process of foundation step C geometric data makeover process or one dimension geometric data, draws the visuals of the reinforcing bar schematic diagram generated; 2. described information labeling, is by the engineering attribute of three-dimensional rebar model that extracts in steps A rebar model information extraction process and the geometry information of model segment, is labeled in the corresponding segments of schematic lines as word content.

By reinforcing bar schematic lines and information labeling typing respective cells, obtain reinforcing bar form.

Detailed process of the present invention and embodiment as follows:

Embodiment one: the gateway opening pattern reinforcing bar in unit spiral case layer and following peripheral model draft tube exit, three-dimensional rebar model as shown in Figure 4.

A, rebar model information extraction: the engineering attribute and the space geometry information that first extract three-dimensional rebar model.Engineering attribute refers to the attribute relevant to engineering that engineering significance representated by three-dimensional model and model itself are designed personnel and give, in this embodiment, model engineering attribute comprises reinforcing bar classification, grade, diameter, spacing, reinforcing bar numbering, reinforcing bar place elevation, face, reinforcing bar place.

The space geometry information of model comprises number of fragments and the segmentation geometric attribute of model, and segmentation geometric attribute refers to the type of segmentation, physical dimension and controling parameters, and Segment type comprises line segment, circular arc, elliptic arc and SPL.In the present embodiment, rebar model can be divided into five sections, and Segment type is respectively line segment, line segment, circular arc, line segment, line segment.The physical dimension of each section and controling parameters be as shown in Figure 2: the physical dimension of line segment comprises line segment length, and controling parameters comprises extremity of segment point coordinate and normal vector; The physical dimension of circular arc comprises radius, arc length and central angle, and controling parameters comprises arc method vector, centre point coordinate, circular arc start angle and circular arc termination point.

B, geometric data convert: the geometric data of former three-dimensional is converted to the easier two dimension expressed on drawing or one dimension geometric data, the reference mark of the three-dimensional reinforcing bar extracted in steps A process is spatial point, cannot directly sign on drawing, this process is two-dimensional coordinate the reference mark coordinate conversion of former three-dimensional reinforcing bar, and all reference mark Z coordinate after changing is 0.Geometric data conversion comprises coordinate translation conversion and rotational transform two parts of coordinate: coordinate translation converts and refers to that the transformation matrix of this process is the translation matrix of 3 X 1 by the coordinate translation at the rebar model reference mark of optional position in three dimensions near drawing coordinate initial point; Rotating Transition of Coordinate refers to a reference mark on three-dimensional rebar model for reference point, and by rotating to an angle, by three dimensions, rebar model data rotation is on drawing plane at any angle, and the transformation matrix of this process is the rotation matrix of 3 X 3.

In general, although reinforcing bar distribution in three dimensions, still belong to planar object, namely each segmentation of reinforcing bar is in same plane.System is by all reference mark of reinforcing bar, automatically the plane at reinforcing bar place is extracted, with the starting point at reference mark for initial point, the normal direction of the longest section of reinforcing bar is that X-axis sets up local coordinate system, is then transformed into by all Three dimensions control point coordinate in the local coordinate system just set up by origin translation and X-axis rotate.

C, geometric data correction: the geometric data after conversion is revised, makes the schematic diagram of drafting meet the standard of publishing picture.Geometric data correction is divided into overall convergent-divergent and segmentation to adjust two parts.The rebar model set up according to Practical Project size is zoomed to the pre-sizing of drawing by overall convergent-divergent process, and in overall convergent-divergent process, the scaling that model is each section is identical; Segmentation adjustment refers to carry out convergent-divergent adjustment separately to each segmentation, and ensure that the size of each segment figure after adjustment is all in rational scope, be unlikely to excessive or too small, in this process, the proportionate relationship that model is each section can change to some extent.

Perform overall convergent-divergent, first the area size at two dimension or place, one dimension geometric data all reference mark is obtained, then the size in this region and target area size (being in general the cell size of the placement schematic diagram of reinforcing bar form) are compared, obtain a scale factor, by the reference mark that this scale factor convergent-divergent is all.

Execution segmentation adjusts, and the length of each segmentation and the limit value I of setting and limit value II contrast, and limit value II is greater than limit value I, and section length is less than adjusting according to the scale factor of itself and limit value I of limit value I, is greater than limit value I to its length; Section length is greater than adjusting according to the scale factor of itself and limit value II of limit value II, is less than limit value II to its length.Rebar model first in the present embodiment, the 5th section too short, if draw schematic diagram according to the original scale of each section of three-dimensional reinforcing bar completely, the first of reinforcing bar schematic diagram, the 5th segment length can be caused too little to such an extent as to mark word cannot be write, therefore also need to amplify separately the first, the 3rd section, ensure that the minimum length of each section is not less than some limit values, and the size marking word of this section can be write.After adjustment, model second segment and the 4th section longer, although do not affect schematic information to express, but the schematic diagram of generation can be made to take more bar list space, affect attractive in appearance, therefore also need to carry out independent convergent-divergent to the second, the 4th section, ensure the size marking word that can either write this section, have and be unlikely to oversize and affect aesthetic property, the process of segmentation adjustment as shown in Figure 5.

D, drafting reinforcing bar schematic diagram: reinforcing bar schematic diagram is drawn and comprised reinforcing bar schematic lines and information labeling two parts.Reinforcing bar schematic lines be according to the process of step C process after two dimension or a dimension geometry certificate, draw the visuals of the reinforcing bar schematic diagram generated; Information labeling is by the engineering attribute of three-dimensional rebar model that extracts in steps A process and the geometry information of model segment, is labeled in the corresponding segments of schematic lines as word content.The reinforcing bar schematic diagram of final generation as shown in Figure 6.

Embodiment two: three sections of pattern reinforcing bars at unit spiral case layer and following peripheral model top, reinforcing bar pattern as shown in Figure 7.

A, rebar model information extraction: the engineering attribute and the geological information that first extract three-dimensional rebar model.Engineering attribute refers to the attribute relevant to engineering that engineering significance representated by three-dimensional model and model itself are designed personnel and give, in this embodiment, model engineering attribute comprises reinforcing bar classification, grade, diameter, spacing, reinforcing bar numbering, reinforcing bar place elevation, face, reinforcing bar place.

In the present embodiment, rebar model can be divided into three sections, and three Segment types are all line segments, and size is respectively 1130,15315 ~ 16150 (△=60), 1130, unit mm.Three sections of controling parameters are terminal coordinate and segment method vector.

The controling parameters controling parameters of the first segmentation is:

[StartPoint(-53109.0000,-8800.0100,87673.0000)]

[EndPoint(-53109.0000,-8800.0100,88799.0000)]

[Vector(0,0,1)]

The controling parameters controling parameters of the second segmentation is:

[StartPoint(-53109.0000,-8800.0100,88799.0000)]

[EndPoint(-37851.0000,-8800.0100,88799.0000)]

[Vector(1,0,0)]

The controling parameters controling parameters of the 3rd segmentation is:

[StartPoint(-37851.0000,-8800.0100,88799.0000)]

[EndPoint(-37851.0000,-8800.0100,87673.0000)]

[Vector(0,0,-1)]。

B, geometric data convert: the geometric data of former three-dimensional is converted to the easier two dimension expressed on drawing or one-dimensional data, the reference mark of the three-dimensional reinforcing bar extracted in steps A process is spatial point, cannot directly sign on drawing, this process is two-dimensional coordinate the reference mark coordinate conversion of former three-dimensional, and all reference mark Z coordinate after changing is 0.Geometric data conversion comprises coordinate translation conversion and rotational transform two parts of coordinate: coordinate translation converts and refers to that the transformation matrix of this process is the translation matrix of 1 X 3 by the coordinate translation at the rebar model reference mark of optional position in three dimensions near drawing coordinate initial point; Rotating Transition of Coordinate refers to a reference mark on three-dimensional rebar model for reference point, and by rotating to an angle, by three dimensions, rebar model data rotation is on drawing plane at any angle, and the transformation matrix of this process is the rotation matrix of 3 X 3.

In general, although reinforcing bar distribution in three dimensions, still belong to planar object, namely each section of reinforcing bar in same plane.System is by all reference mark of reinforcing bar, automatically the plane at reinforcing bar place is extracted, with the starting point at reference mark for initial point, the normal direction of the longest section of reinforcing bar is that X-axis sets up local coordinate system, is then transformed into by all Three dimensions control point coordinate in the local coordinate system just set up by origin translation and X-axis rotate.

In the present embodiment, translation matrix is:

|53109.0000 8800.0100 -87673.0000|

Rotation matrix is:

|1.0000 0.0000 0.0000|

|0.0000 0.0000 1.0000|

|0.0000 1.0000 0.0000|。

C, geometric data correction: the geometric data after conversion is revised, makes the schematic diagram of drafting meet the standard of publishing picture.Geometric data correction is divided into overall convergent-divergent and segmentation to adjust two parts.The rebar model set up according to Practical Project size is zoomed to the pre-sizing of drawing by overall convergent-divergent process, and in overall convergent-divergent process, the scaling of each segmentation of model is identical; Segmentation adjustment refers to carry out convergent-divergent adjustment separately to each segmentation, and ensure that the size of each segment figure after adjustment is all in rational scope, be unlikely to excessive or too small, in this process, the proportionate relationship that model is each section can change to some extent.

Perform overall convergent-divergent, first the area size at place, all reference mark is obtained, then by the size in this region and target area size (being in general the cell size of the placement schematic diagram of reinforcing bar form), compare, obtain a scale factor, by the reference mark that this scale factor convergent-divergent is all;

Execution segmentation adjusts, and the length of each segmentation and the limit value I of setting and limit value II contrast, and limit value II is greater than limit value I, and section length is less than adjusting according to the scale factor of itself and limit value I of limit value I, is greater than limit value I to its length; Section length is greater than adjusting according to the scale factor of itself and limit value II of limit value II, is less than limit value I to its length.In the present embodiment, rebar model second segment is oversize, if draw schematic diagram according to the original scale of each section of three-dimensional reinforcing bar completely, the first of reinforcing bar schematic diagram, the 3rd section too short can be caused to such an extent as to cannot see completely, therefore also need to carry out independent convergent-divergent to the first, the 3rd section, ensure that the minimum length of each section is not less than some limit values, and the size marking word of this section can be write;

After data transformation and convergent-divergent, the controling parameters that model is each section is as follows:

The controling parameters controling parameters of the first segmentation is:

[StartPoint(0.0000,0.0000,0.0000)]

[EndPoint(0.0000,10.0000,0.0000)]

[Vector(0,1,0)]

The controling parameters controling parameters of the second segmentation is:

[StartPoint(0.0000,10.0000,0.0000)]

[EndPoint(24.0000,10.0000,0.0000)]

[Vector(1,0,0)]

The controling parameters controling parameters of the 3rd segmentation is:

[StartPoint(24.0000,10.0000,0.0000)]

[EndPoint(24.0000,0.0000,0.0000)]

[Vector(0,-1,0)]。

D, drafting reinforcing bar schematic diagram: reinforcing bar schematic diagram is drawn and comprised reinforcing bar schematic lines and information labeling two parts.Reinforcing bar schematic lines be according to the process of step C process after two dimension or one dimension geometric data, draw the visuals of the reinforcing bar schematic diagram generated; Information labeling is by the engineering attribute of three-dimensional rebar model that extracts in steps A process and the geometry information of model segment, is labeled in the corresponding segments of schematic lines as word content.Final generation reinforcing bar schematic diagram, as shown in Figure 8.

Fig. 9 is that the part reinforcing bar form that certain hydroelectric project unit spiral case layer and following peripheral rebar model extract is shown, is formed by the reinforcing bar schematic lines of each segmentation and the corresponding cell of information labeling typing.

Claims (3)

1. a method for drafting for three-dimensional reinforcing bar model schematic, is characterized in that step is as follows:

A, rebar model information extraction, for reading engineering attribute and the space geometry information of three-dimensional rebar model, the space geometry information of model comprises number of fragments and the segmentation geometric attribute of model, segmentation geometric attribute refers to the type of segmentation, physical dimension and controling parameters, and Segment type comprises line segment, circular arc, elliptic arc and SPL;

B, geometric data convert, and the geometric data of former three-dimensional is converted to the easier two dimension expressed on drawing or one dimension geometric data by coordinate translation conversion and Rotating Transition of Coordinate;

C, geometric data correction, carry out overall convergent-divergent and segmentation adjustment successively to the two dimension after conversion or one dimension geometric data;

Overall convergent-divergent, the two dimension of three-dimensional rebar model or one dimension geometric data entirety are zoomed to pre-sizing, and in overall convergent-divergent process, the ratio of each section of model remains unchanged;

Segmentation adjusts, separately convergent-divergent adjustment is carried out to each segmentation, too small segmentation schematic lines is amplified to be easy to identification line segment type and mark line segment size, and long segmentation schematic lines is contracted to be easy to the typesetting of reinforcing bar schematic diagram in bar list and overall appearance;

D, drafting reinforcing bar schematic diagram, carry out the drafting of each group reinforcing bar schematic diagram, each group reinforcing bar schematic diagram is drawn and is comprised reinforcing bar schematic lines and information labeling two parts, wherein reinforcing bar schematic lines is two dimension or the one dimension geometric data of step C gained, and information labeling is the engineering attribute of three-dimensional rebar model and the physical dimension of model segment in steps A;

By reinforcing bar schematic lines and information labeling typing respective cells, obtain reinforcing bar form.

2. the method for drafting of three-dimensional reinforcing bar model schematic according to claim 1, it is characterized in that: the overall convergent-divergent of step C, first the area size at two dimension or place, one dimension geometric data all reference mark is obtained, then the size in this region and target area size are contrasted, obtain a scale factor, by the reference mark that this scale factor convergent-divergent is all; Described target area size is the cell size of placing reinforcing bar schematic diagram in reinforcing bar form.

3. the method for drafting of three-dimensional reinforcing bar model schematic according to claim 1, it is characterized in that: step C segmentation adjusts, obtain the length of each segmentation and the limit value I of setting and limit value II contrast, limit value II is greater than limit value I, section length is less than adjusting according to the scale factor of itself and limit value I of limit value I, is greater than limit value I to its length; Section length is greater than adjusting according to the scale factor of itself and limit value II of limit value II, is less than limit value II to its length.