A cross beam flexure pivot assembly is a device which secures to and supports a mechanism and transmits to the mechanism well-defined limited rotational movement about a radial axis of rotation. Cross beam flexure pivot assemblies are used, for example, in supporting a mechanism which requires precise pointing throughout the limited rotation of the mechanism. Cross beam flexure pivot assemblies are configured to avoid friction in a desire to obtain reliable and repeatable pointing throughout the limited rotation. Flexing beam members connect two parts of the cross beam flexure pivot assembly, which have limited rotation relative to one another, such that the two parts are not positioned in frictional contact with one another in the interest of providing precise limited rotation of the supported mechanism in a repeatable plane.
Cross beam pivot flexure assemblies have unequal moment stiffness in different directions with respect to the flexing beams, which can present difficulty, for example, in sustaining precision pointing by the mechanism supported by the cross beam flexure pivot assembly. Cross beam flexure pivot assemblies used, for example, to support a cantilevered load of the mechanism, normally would be designed using the softer direction moment stiffness of a cross beam pivot flexure assembly, requiring a larger or heavier flexure design that can reduce system pointing performance in a precision tracking system. There is a need to provide cross beam flexure pivot assembly support to cantilevered loads such that the cantilevered load can be supported with an optimally sized cross beam pivot flexure allowing maximum pointing performance with a given mass and volume constraint.