CHAOTIC PENDULUM BASED ON TORSION AND GRAVITY IN OPPOSITION

An unconventional driven torsion pendulum influenced by gravity has been studied for chaos. Through the use of a symmetric differential capacitive sensor and a galvanometer, phase-space trajectories were generated with an x-y recorder. These were then later compared against output from a computer model of the system which has been further used to generate Poincare sections, Fourier transforms, and time records. Sensitive dependence on initial conditions as a function of frequency and drive amplitude was demonstrated. (C) 1995 American Association of Physics Teachers.