Often times, the supplier will have an image of curve, but no data points to download...so how do you obtain the data points easily and somewhat accurately?
I've imported images into Solid Edge before, scaled them, and used them as profiles for my model (reverse engineering parts that had a lasered profile), so I figured why not use that technique to discretize the curve.
Step 1: In a new part file, start a new sketch, and insert the image.
Step 2: You need to scale the image. Since the Y axis has known values, I created a line that was 9000 inches long, then scaled the image to match.
Step 3: I then drew line segments to approximate the curve.
Step 4: Add coordinate dimensions to the endpoints of each line and you now have data points to use in your FEA software of choice. Note, the X-axis dimensions in Figure 1 don't match my Solid Edge dimensions, which meant a scale factor must be used to calculate the respective strain value.
Step 5: I added these points into my nonlinear material in Femap.
Thanks for taking time to read this and let me know if you have any questions.
- David Haag