Constructing the Bode Plot

In the process of drawing a Bode Plot, I have construct a plot including 400 times the frequency of the KUKA and 100 times of the force data.

The x-axis marks the period of the peaks and troughs of the increasing frequency of the KUKA robot. I am assuming the rate of increasing frequency is constant within each period, using that to calculate the frequency of each point to plot the frequency response which leads to the Bode Plot.