Figure 36.

Shifts of frequency in panel (A) and bandwidth in panel (B) as computed with an FEM simulation for the configuration shown in Figure 35. There are two separate coupled resonances. These are the consequence of two dynamical variables, which are translation and rotation. Translation and rotation are always coupled, but there are two special linear combinations of translation and rotation, which both produce a resonance. Only the transverse force at the point of contact shifts Δf and ΔΓ, a torque does not take an influence. The relative importance of the force compared to the torque is larger for the high-frequency mode. The sphere rotating about the point of contact mostly exerts a torque. This low-frequency mode therefore appears as less pronounced when probed with the QCM. Adapted from [171].