This is an overview of several cycles, to illustrate the data for further analysis below.

The top “lane” of data is from the right-hand unloader accelerometer, in raw format (zero is at mid-line).

The bottom “lane” of data is torque from the strain gages mounted on the motor reaction torque tube. This is scaled in Nm *100 – that is, 2.0 = 200 Nm. This is from the lower right unloader motor.

The vertical blue dotted lines are “markers” which can be positioned to measure signal features: in this image the top line of text gives the time interval between the 2 markers as 5.000s, which equates to 12 strokes per minute as I picked the start of two consecutive machine cycles.

This image is a closer look at one representative cycle. The torque data is particularly interesting in that it reveals a high degree of pulsation in torque, including rapid torque reversals in mid-stroke.

This is a zoom-in of the torque pulsation in a portion of the cycle, with markers used to measure the period of the pulses, which in this particular case is 35ms – the inverse of this is 28 cycles per second.

Here is another measurement in the same cycle, during a more aggressive acceleration interval. Here the torque pulsation can be seen reflected in the acceleration.

Here are photos of the accelerometer location:

Unloader Accelerometer is here

Loader Accelerometer is here (same slice as the unloader)

Gearbox

Motor

Strain Gage sites