|On 16 May 1998, Felix Leonidovich Chemous'ko, a leading scientist in
the field of mechanics and control theory, celebrated his sixtieth birthday.
The wide range of his research interests and achievements covers the dynamics of rigid bodies con-taining cavities with liquid or movable internal masses, the theory of optimal control, the theory of dif-ferential games, vibration theory, the theory of the esti-mation of the state of dynamical systems, computational methods of variational calculus and optimal control, and robotics. The important results he obtained in these ar-eas have been recognized both in Russia and abroad.
During the 1960s, he carried out a large series of researches on the dynamics of a rigid body with cavities containing a liquid. Using the classical methods of separation of motions, he studied the angular motion of the body depending on the shape of the cavity, the extent to which it was filled, and the viscosity of the liquid.