Instruments can include
coupling interfaces that can b used, for example, for
coupling a
surgical instrument to a navigation array or other component. An exemplary
coupling can include a first coupling interface associated with a first object, such as a
surgical instrument, and a second coupling interface associated with a second object, such as a navigation array. The coupling interfaces can be configured to ensure that, when mated, the first and second objects are disposed in a known position and orientation relative to one another and blocked from relative movement in all
six degrees of freedom. The interfaces can have a geometry that is not overdetermined, minimizing or eliminating navigation inaccuracy associated with
system tolerances. An exemplary coupling can include counterpart centering features for blocking X-axis translation and Y-axis translation, counterpart rotation stops for blocking Z-axis rotation, counterpart reference planes for blocking X-axis rotation, Y-axis rotation, and Z-axis translation in a first direction, and a locking element for blocking Z-axis translation in a second, opposite direction.