See Add Point-Cloud
Use a Point Cloud to:
Import-data as a text-file.
Use the Point-Cloud dialog-box to import data.
Typically, the data are coordinates of a cam-profile, which are measured with a Coordinate Measurement Machine (CMM). The measurement data are taken 'as is'. Numerical techniques calculate motion-derivatives, but the higher derivatives are usually noisy.
Fit-a-Curve to the imported-data.
Use Point-Cloud dialog-box to fit a Curve to the Imported-Data.
The Curve is a continuous-function that is a good-fit to the imported-data. We use the continuous-function to evaluate motion-derivatives, which are usually smooth.
Open the Point-Cloud dialog-box
Import a text file of data that you want to use as the Point-Cloud.
Do A, B, and C
Click the Browse... button to select data-file you want to import.
The file-name will show in the File-name to Import (Read-Only) box
B. Edit File-Format
Each row of data in the data-file must include:
•X & Y coordinates, or
•R & Θ coordinates.
Each data-point must be a new line, and ideally only two columns of data.
However, not all data-files have only two columns of data.
Use the Edit File-Format box to remove extra columns of data from the data-file
See File Formats below.
c. Import button
Click the Import button to import the Point-Cloud data file.
If successful, the Point-Cloud will show as a continuous line in the graphic-area immediately.
See also: Messages
x , y
When you add a Point-Cloud, you select a Part. The Part has an Origin - its start-Point - where its XY coordinates are (0,0)
If the Point-Cloud data has a measurement offset, then remove the offset with the X and Y data boxes.
Or, If you want to offset the Point-Cloud data by an offset, then add the offset.
File Rotary Units ; File Linear Units
Select the units that match those of the original Point-Cloud data-file
Pre-Select a File Format
To help you with the formatting, you can use the Pre-Select a File Format drop-down list-box.
When any of these formats do not represent the format of the data in your data-file, then edit the format in the Edit File Format box directly.
Example Data-Files & File-Formats.
When you successfully import a Point-Cloud, the chart shows the Point-Cloud in (Dark Blue) and the Continuous Curve in (Light-Blue).
Fit a Continuous Curve to the Point-Cloud Data
A.Original Data Accuracy
This is a judgment you must make. I enter 0.1, then reduce it to approximately 0.01 - see below for more thoughts.
B.Auto-Fit check-box and Fit Curve button
Usually, you can click the Auto-Fit... check-box to put a tick in the check-box - see options
C.Increase the # Harmonics
Edit the # Harmonics
The Continuous-Curve improves each time you edit the # Harmonic.
D.Fit-Quality =~1 ?
When Fit Quality Traffic Light becomes Green, STOP, or
When the number in the Fit-Quality Number box is near to, or equal to, one (1), STOP
If you add more harmonics, the fitted-curve may oscillate with an amplitude equal to the Original Data Accuracy.
Click one of the four radio buttons:
•Point and Curve
Clear the Auto-Fit check-box if the Point-Cloud has many points. E.g. > 10000 points / lines.
You must click use the Fit Curve button to update the Fitted-Curve,
Repeat until the Fit-Quality and the Traffic-Light becomes Green or Orange
Velocity and Acceleration Filter Width
The default plot is for Position. I do not use the V or the A buttons as I cannot find a good use to do so.
•If you want to look at the plot of the Point-Cloud as Velocity or Acceleration (), then click the V or the A icons.
•If the Point-Cloud Data is noisy you can smooth the Velocity or Acceleration data. Use the Filter Width to remove some of the noise from the data. This may help you identify the original Motion-Law.