In the paper, a new form of differential equations for rigid body attitude dynamics is obtained. Three s-parameters (modified Rodrigues-Hamilton parameters) and three angular velocity parameters are used as unknown variables. Built equations are particularly useful for analytical and numerical study of rotational motion of a rigid body. The topological structure of configurational s-manifold for a balanced rigid body is investigated. An example of the use of constructed equations to describe the rotational motion of a rigid body in a resisting medium is considered