Hello, does this mean that in the frequency range of concern, the more resonance peaks, the more suitable it is to paste the acceleration sensor here??? If you need to select two points, then point 1 is the most appropriate and point 4 is more appropriate. Is this the case??? Thank you and look forward to your reply
For a given structure, the more peaks in a driving point FRF the better, as this means you are exciting more modes by exciting there (Point 1 vs Point 4). However, you can also choose multiple driving points for a given structure, you will just end up taking 2x the data, which may result in a higher quality modal analysis, or yield additional modes. For example: Accel at Pt 1, Rove Hammer to points 1-15 = 15 FRFs. Next, Accel at Pt 4, Rove Hammer to points 1-15 = 15 more FRFs (total 30 FRFs). However, for this simple plate we likely won't gain any additional useful information from the Driving Point #4 FRFs as all the information extracted from this location was already extracted by impacting at Point #1 (Point 1 driving point FRF had all the peaks from Point 4 driving point, plus more). Usually when additional driving points are added they are performed in a different direction (not vertical) to excite different modes than a vertical excitation.
@@SimcenterTesting Thank you for your reply; I have a question here. Generally, the reference point of modal test should be fixed; If I have only one sensor, can I fix the sensor at reference point 1, move the hammer to traverse all points, then fix the sensor to reference point 2, and move the hammer to traverse all points again, so that I can get more FRF curves. Can I do this? We look forward to your reply
Hello, does this mean that in the frequency range of concern, the more resonance peaks, the more suitable it is to paste the acceleration sensor here??? If you need to select two points, then point 1 is the most appropriate and point 4 is more appropriate. Is this the case??? Thank you and look forward to your reply
For a given structure, the more peaks in a driving point FRF the better, as this means you are exciting more modes by exciting there (Point 1 vs Point 4). However, you can also choose multiple driving points for a given structure, you will just end up taking 2x the data, which may result in a higher quality modal analysis, or yield additional modes. For example: Accel at Pt 1, Rove Hammer to points 1-15 = 15 FRFs. Next, Accel at Pt 4, Rove Hammer to points 1-15 = 15 more FRFs (total 30 FRFs). However, for this simple plate we likely won't gain any additional useful information from the Driving Point #4 FRFs as all the information extracted from this location was already extracted by impacting at Point #1 (Point 1 driving point FRF had all the peaks from Point 4 driving point, plus more).
Usually when additional driving points are added they are performed in a different direction (not vertical) to excite different modes than a vertical excitation.
@@SimcenterTesting Thank you for your reply; I have a question here. Generally, the reference point of modal test should be fixed; If I have only one sensor, can I fix the sensor at reference point 1, move the hammer to traverse all points, then fix the sensor to reference point 2, and move the hammer to traverse all points again, so that I can get more FRF curves. Can I do this? We look forward to your reply