PartsPerArea

Description of the app:
2D Cutting optimization for identical parts of any shape

The app calculates the maximum number of similar parts of a given shape and
size that can be accommodated on a given rectangular area.

The app is intended for all users who want to cut identical parts out of a rectangular, flat material.
The app user receives information about the material requirements and the optimal placement of the parts.

The calculated maximum number of parts and the percentage utilization of the area are displayed as the result.
The optimization result is displayed graphically and can be saved as a DXF file.


Special features:
• 2D cutting optimization for parts of any shape
• Consideration of a tool diameter or a minimum safety distance between the parts
• CAD interface
• Easy to use: If the accuracy requirement is slightly reduced, a photo of the part is sufficient
• Data entry and analysis result within 90s


In addition to rectangles and circles, profiles that can have any shape can be selected as parts.
For the "Profile", the description of the part must be imported. There are 3 import options
available:
• DXF file, NC program
• Graphic as bitmap file
• Photograph

Placing methods:
• Standard: No rotation
• Optimized: The parts are rotated


Input parameters for the profile optimization calculation:
• "Area Length"
• "Area Width"
• "Tool diameter"


Start of optimization (button "Calculate") :
After entering the parameters and importing the profile description, the optimization calculation can be started. If an invalid parameter configuration is detected, an error message appears with instructions on how to fix it.


Import of a profile part description (button "Import"):
The description of the part must be imported in the form of a CAD file (*.dxf), an NC program file (*.txt), or a graphic file (*.jpg, *.jpeg, *.gif, *.bmp, *.png).


Photo as profile part description (button "Photo"):
A photo of the part can also be used as a profile description. It must be noted that image distortions can occur when taking photos.

After taking photos, a rectangular image section can be defined using a cropping function. Only this image section is then evaluated.

Requirements for a usable photo:
The part must stand out clearly from the background of the image. The background must also be as uniform and unicoloured as possible.
When photographing objects, it is recommended to use a white sheet of paper as a background. Any shadow of the object can be minimized using the flash function. Light problem areas can be covered with dark adhesive tape.



Special features of bitmap import and photography:
When importing a bitmap file or using a photo, the user must also specify the dimensions of the part ("length of the part") or ("width of the part"), as no information about the dimensions of the part is available.
To determine the part dimensions, the part can be aligned by rotating it. The gray rectangle shown corresponds to the part dimensions that are used for optimization.
The imported part can be saved as a DXF file or as an NC program. This saved profile description file can be imported again later for further calculations.

Importing a DXF file or an NC program as a profile part description:
Processing these two data formats yields the highest calculation accuracy.

Note about the CAD-DFX format: Not all CAD programs and CAD viewers support the DFX INSERT command used.
Recommended viewer: LibreCAD

The NC program must be stored in a text file. The NC program specifies the part contour from the start point to the end point of the contour. The start and end points must be identical. Only the outer edge of the part may be programmed.

Not all standard G code instructions are supported. Unknown G codes are ignored.

List of supported G codes:

• G1, G01:               Linear interpolation (default)
• G2, G02:               Circular interpolation clockwise
• G3, G03:               Circular interpolation counterclockwise
• X<Pos>:                Block target point, X coordinate
• Y<Pos>:                Block target point, Y coordinate
• Z<Pos>:                Block target point, Z coordinate
• I<Cen>:                 Circle center point, X coordinate
• J<Cen>:                Circle center point, Y coordinate
• K<Cen>:                Circle center point, Z coordinate
• R<Rad>:                Circle radius

                                     Circle angle < 180deg? --> R = radius
                                     Circle angle >= 180deg? --> R = -radius

• G17:                       XY plane selection (default)
• G18:                       XZ planen selection
• G19:                       YZ plane selection
• G161:                     Absolute circle center coordinate programming
• G162:                     Relative IJK circle center value programming (default)

Programming notes
The setting G codes G17, G18, G19, G161 und G162 must be programmed before the first motion block (G1, G2, G3).

In the case of relative IJK circle center value programming (G162), the IJK circle center value must be calculated according to the following rule:
IJKPosition[X,Y,Z] = CircleCenter[X,Y,Z] - StartPosition[X,Y,Z]

IJKPosition[X,Y,Z]:      Relative circle center point coordinates
CircleCenter[X,Y,Z]:    Circle center point coordinates
StartPosition[X,Y,Z]:   Start point of the current NC block.

The start point of the current NC block corresponds to the target point of the preceding NC block.

NC program example:
G17 G162
G1 X100 Y0               ;Start point
G1 X100 Y100
G1 X-100 Y100
G1 X-100 Y0
G1 X-70 Y0
G2 X-20 Y50 I50 J0  ;alternative: G2 X-20 Y50 R5
G1 X20 Y50
G2 X70 Y0 I0 J-50    ;alternative: G2 X70 Y0 R50
G1 X100 Y0               ;End point