The experiment was taken place on Monday with the help of Yang and Lin. The KUKA robort was facing downwards originally, as I explained what I would like to do, Yang tried to move the end-effector upward. Yang struggled for nearly twenty minutes but it was unsuccessful in the end. The best we could achieve was to have the end-effector perpendicular to ground, thus the end-effector moves parallel to ground. In this case, I had to held the probe away form its normal position but lying down. Due to the tolerance in between the motor and the spindle, stronger vibration could be felt immediately.
In the first experiment, we have set the KUKA to oscillate with increasing frequency. We started slow, having it move one cycle per second. The performance of the probe was very good. However, as we increase the frequency to 5 cycles, the performance started to degrade. This started earlier than I originally thought, after a little fettle around, I discovered having the probe in a flattened position decrease the effective speed of the motor. I tried to increase the speed in the program to improve the performance, however this also introduced some extra vibration to the system. With the vibration, the raw data looks very noisy, they need to be filtered before moving onto plotting a Bode plot.
In the second experiment, the probe was set to follow the motion of the KUKA when the position of the holder was kept constant. The probe followed the end-effector closely with a phase shift.
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