Performing a Deviation Analysis

• Reference data can be a volume, a surface, a plane, a point, a curve, or a cloud of points.
• To measure data can be clouds of points, points, curves, surfaces, or volumes.
• When the data To measure are curves, surfaces, or volumes, they are discretized.
• Multiselection is available:
• is available to hide or show the Reference and the To measure data.

• Determine the discretization Accuracy, available only when at least one curve, volume, or surface is selected as Reference.
• Select Only Orthogonal to eliminate points that are not projected orthogonally on the Reference:
• Select Absolute to perform the analysis with absolute values only.
• When the Reference is a curve, a surface or a body, and for more precise results, select Exact to project the To measure geometry on the Reference exact curve (instead of on its discretization) , or on exact surface (instead of on its tessellation). The projection is either orthogonal or along the chosen direction.
• Select Direction to define a projection direction by picking a plane or a line.
  Notes:

  • Right-click Direction and select the required menu item.
  • Or right-click the Robot and select Lock Privileged Plane Orientation Parallel to Screen and Robot Direction.
  • If you change the direction, do not forget to update the deviation analysis feature.

• Select Spikes to activate the visualization of the spikes.
• Select Points to change the display to points.
• Click Options to customize the display of Spikes and Points. Use
  • Spike scale to change the length of the spikes.
  • Point to change the display symbol of points.
• Select Texture to display the deviations as textures.
  Notes:

  • Texture is applied to the data To measure.
  • The data To measure must be a mesh, a surface or a volume.
  • The Render Style must be Shading with Material. If this is not the case, a message asks you to switch to this Render Style.
  • Texture mode is available on meshes only, their display mode being either Flat or Smooth.
  • Texture mode is always available but only triangles with values on their three vertices are displayed. In the example below, the triangles on the top and on the left are not displayed in Texture mode.
    
    
  • There must be a color for each value. The No color and the Hide dimmed points options apply to spikes and points visualizations only. They have no effect on texture mode.
• Select Max values to display the maximum deviation values (positive and negative) and their locations on the data To measure.

• Select Homogeneous filtering to reduce the number of points of the data To measure to take into account. A sphere filtering is applied. The parameter represents the radius of this sphere.
• Select Threshold to remove points with a deviation higher than this threshold.
• Select Step when the data to measure are curves, surfaces, oror volumes. It controls the length of the discretization triangles f surfaces or volumes, or of the segments for curves. If you do not select this check box and enter a value, Deviation Analysis computes the step, but in some cases it is better that you define your own step value.

• Style: three styles are available:
  • Scientific
  • Decimal
  • Automatic
• Define the Number of significant digits between 1 and 15.

• If With distances is cleared, the data is exported as x y z dx dy dz.

  x(mm)	y(mm)	z(mm)	dx(mm)	dy(mm)	dz(mm) 
  10000	2000	0	-6620.91	-3940.1	-8.91151e-014

• If With distances is selected, the data is exported as x y z dx dy dz d, where d is the distance, absolute or signed depending on the option chosen for the deviation analysis.

   
  x(mm)	y(mm)	z(mm)	dx(mm)	dy(mm)	dz(mm)	d(mm) 
  10000	2000	0	-6620.91	-3940.1	-8.91151e-014	7704.6

1. Change the value and recompute intermediate values.
   • The Recompute intermediate values check box is displayed once a value has been changed.
   • A warning message is displayed if you enter an inconsistent value.

You cannot modify the colors in Smooth mode.

• You cannot modify the values in Equalization mode.
• This mode is not always possible (for example concentration of points on one value).
• There is one distribution for the positive values and one for the negative values.

• All: Selects all the items below (Results, Statistics, Tolerances, Histogram).
• None: None of the items below (Results, Statistics, Tolerances, Histogram) is selected.
• Results
  
  
• Statistics
  
  
• Tolerances
  
  Double-click the tolerance to edit it.
• Histogram
  
  

You can combine all these options.

Points are dimmed for three reasons:

• They are out of the color map: the max. values are [0,10], you change them to [0,5]. The points inside [5,10] are dimmed.
• They are inside the tolerance and the option Dim points inside the tolerance is selected.
• They are outside the tolerance and the option Dim points outside the tolerance is selected.

This menu item:

• Is available only if the Tolerances option is selected.
• Dims the points that are within the tolerance.
• Those points can then be hidden with the option Hide dimmed points.

This menu item:

• Is available only if the Tolerances option is selected.
• Dims the points that are not within the tolerance.
• Those points can then be hidden with the option Hide dimmed points.