Navigation:  Tutorials > Measurement tutorials > Vibration > DEWESoft 7.0  data acquisition, processing, analyzing and storage software Analysis

In the analysis mode we can look through the data. Here, one picture is put on top of another to see the movement of the beam. The first picture below is the upper point of displacement.

On the scope on the right, we can see nicely that the Vib1 and Vib2 are phase shifted for 90 deg . Thus, the user is in the clear region of the natural frequency of this structure.

On the recorder graph below, we can analyze the acceleration, the velocity and the displacement. The displacement (green curve) is in the upper position , which can be visually confirmed with the video . The velocity (the red curve) is zero - this is also clear because the upper point is a turnaround and before reaching this point on the top, the velocity is decreased and at the top point, the velocity is zero. The acceleration (blue curve) at the top is at maximum in the negative direction . Acceleration is the rate of change of the velocity. We can see from the velocity curve that the rate of change is at a maximum at the top; therefore the acceleration is as its maximum at the top dead point.

 

Now let's go to the next significant point of the movement - the center point. We can see that it is the center point because the displacement is in the middle . The velocity in the center is at a maximum in the negative direction . This is makes sense: the beam is reaching the middle point with maximum velocity, and it will slowly start to decelerate. Acceleration at that point is zero - when a body is standing still or moves with constant velocity, its acceleration is zero . This can be confirmed by observing the blue acceleration curve.

 

 

The third significant point is the bottom point. Here, a top point is shown in background for reference . The displacement is at the lowest point , velocity is zero and will continue to increase, the acceleration is at a maximum in the positive direction  - the speed is changing at a maximum rate at this point.

 

Here, we conducted a simple experiment to get a better feeling about the vibration measurement. In practice, the vibration measurement would surely look different, but we would use the same basic principles as shown in this example.