This paper is organized as follows: in the first section,
we investigate the response of the compound pendulum
to ground vibration using analytical mechanics and
establish the horizontal and tilt transfer functions of the
compound pendulum system, respectively. In the second
section, according to the two transfer functions, we define
four coefficients to describe the performance of compound
pendulum vibration isolation, which dependence with
geometric parameters provides reliable basis for the selection
of the geometric parameters. Finally, the response of
the compound pendulum with the reasonable geometric
parameters to ground horizontal and tilt vibration is calculated
and discussed. The conclusions are given in the last
section.
The schematic layout of cylindrically symmetric
compound pendulum used for the two-dimensional low
frequency ground tilt vibration isolation system is shown
in Fig. 1. The compound pendulum is mainly composed
of a simple pendulum and a U-shape inverse pendulum.
The two pendulums are serially connected each other.
The upper end of the single pendulum is connected to
the suspension point by one elastic reed, and the lower