Dynamic stability of multi-inertial system

Experience has shown that a considerable vibration, due to either hard or soft self-excitation, of the driven end mechanism has often led to many design modifications (through build and test cycle). Conventional techniques of representing driven end mechanism by a ldquoBlack Boxrdquo of lumped parameters fail to identify the source of such undesirable structural oscillations. To make a viable computer model, it needs a more realistic approach, i.e. representing driving and driven end explicitly in terms of the maximum possible number of represent able subsystems. The approach would, indeed, take comparatively more computer time and space but still would be cost effective in identifying the problem and determining a suitable compensation strategy if necessary. Conventional methods to determine system stability does not suit for highly interactive multi-inertial system as each structural element behave differently due to adjoining element. The paper describe AEW radar scanner which is highly interactive electromechanical non-linear system. The scanner has two aerial bodies employed at front and back of the carrier aircraft. Both make azimuth rotation in synchronization mode to cover 360 degree coverage. The elevation rotation is based on demand angle of 5deg degrees in single instance as and when demanded. State Space method is used to define all structural elements cascaded together to count for intra element effects. The paper presents a novel technique to determine dynamic stability; the tendency of their variables or components of a system to remain within defined and recognizable limits despite the impact of disturbances.