A novel "pendulum actuator" was extrapolated from an existing magnetostrictive auxiliary mass damper for generating tonal forces with adaptable operating frequency. The transducer element in the actuator serves to set the pendulum force and therefore the pendulum frequency but can also maintain oscillation of the pendulum mass with an appropriate dynamic driving signal. Two periods of active element elongation are added for each oscillation of the pendulum mass, thereby resulting in larger sinusoidal force amplitudes in comparison with the original force generator design. The operating principle of the novel force generator is established through a detailed review of the mathematical pendulum. The resulting mathematical formulas support the dimensioning of such a pendulum actuator. A laboratory prototype and a measurement documenting its behaviour as a force generator are shown.
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