Support Accessibility Tool
Support Accessibility module is used to visualize and generate the tooling/machining sequence required to remove support structures built for a part using user-input build orientation. For
Instructions
The Accessibility Tool GUI is shown in the figure below. The detailed explanation of each option in the GUI is given below.
Figure 1 Support Accessibility Detection GUI
a) Orientation Independent Directions
The direction of the tool is independent of the build orientation.
6 Cartesian Directions for the tool which are +X, -X, +Y, -Y, +Z, and -Z directions and 8 Cartesian Diagonal Directions for the tool are ±X, ±Y, and ±Z – 8 combinations.
b) Orientation Dependent Directions
The direction of the tool changes as the build orientation changes. The directions are selected as vectors. For selection of directions, click on Add New set and select the vectors using the options available in NX.
c) Select Body
Select the body for which accessibility has to be visualized and analyzed.
d) Rotation
Input rotation of the part along X and Y axes
e) Threshold angle
The angle between the part surface normal and the build direction (Z axis) is entered here. The default value is set to 135 degrees.
f) Overhang Length
Overhang length is the center-to-center distance between two adjacent support columns (square cross-section). It is also the side length of the cross section of the support column (square cross-section). Values ranging from 1.00 to 4.00 are optimal. A lower value will take longer computational time due to a greater number of support structures. A higher value of overhang length will generate fewer support structures making the solution sub-optimal.
- After making the selections for the input parameters in the Accessibility tool GUI, the module requires the user to click the OK button after the accessibility analysis, to go to the next set up (this number depends on the number of tooling sequence), to display in-accessible points, and finally to end the sequential display.
- The output window of the Accessibility module is shown below. The results consist of accessibility index (percentage of supports that can be removed), total points considered and the tooling sequence.
Interpretation of tooling sequence: The tool sequence shows the optimal sequence of directions to remove all the accessible supports. For example, in the output shows below, the optimal sequence would be first removing the support from direction of vector 3 (which can remove 96.15% of supports), and then removing the remaining support from direction of vector 1 (which can remove 0.464% of supports). The vectors are displayed in the CAD geometry and removable supports are shown in different colors with respect to each sequence.
Figure 2 Support Accessibility Output Window
Please watch the video tutorial of the module for an example part included with the zip file of the module.
Example Problem
Use the Parasolid File named Support_Accessibility_Eg_1.x_t in the Example Parts folder attached in the Accessibility Tool folder that you have extracted from the website. Try out the following input configurations to note the changes in Orientation Independent Directions, Orientation Dependent Directions, and Rotation
Figure 3 Support Accessibility Example Problem
a. Select 6 Cartesian Directions in Orientation Independent Directions, Rotate the part along X axis by 35 degrees and rotate the part along Y axis by 50 degrees Set Threshold to default value (135 degrees). Input Overhang Length as 4.00 mm.
b. Select 8 Cartesian Directions in Orientation Independent Directions, Rotate the part along X axis by 45 degrees and rotate the part along Y axis by 0 degrees Set Threshold to default value (135 degrees). Input Overhang Length as 4.00 mm.
c. Select three orthogonal directions along the edges of the cubic body at the origin in Orientation Dependent Directions, Rotate the part along X axis by 0 degrees and rotate the part along Y axis by 0 degrees Set Threshold to default value (135 degrees). Input Overhang Length as 4.00 mm. The directions are shown in figure given below.