Abstract
Similar systems with antisymmetric coupling may be analysed by a root locus technique which is a more general version of the standard method. The normal gain K may be augmented to include antisymmetric coupling γ. and rules for sketching the loci for each value of γ are given.
Filters may be used to add complex poles/zeros without their complex conjugates.
An important class of systems to which the method is relevant is the body having similar pitch/yaw characteristics, and which is spinning at constant rate about its axis of symmetry.