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The impact on the achievable performance and some key structural characteristics in 100-m square solar sails of various design conditions and parameters is explored. Upper-bound performance is addressed with an architecture of manageable mechanics and likely ultimate structural ef ciency in this class of sails due to uniaxial tensioning in each quadrant, namely, the stripped sail. The designs are performed with a limit point friendly approach. These innovations are justi ed by reviewing response fundamentals including sail billow, boom mechanics, and operational failure modes. The observations and conclusions advance the state of the art in sail design and provide guidance for future engineering. Nomenclature a c = characteristic acceleration, mm/s 2 b = square sail edge length, m d = tubular boom diameter, 2r, cm E = boom wall Young's modulus, GPa F = axial boom cross section force, N L = boom length, m l = strip length, m m tot = entire spacecraft mass, kg m 4b = mass of all four booms, kg p = pressure, Pa R Eu = global (Euler) buckling safety coef cient r = tubular boom radius, cm t = lm thickness, ¹m t b = boom wall thickness, mm ± = sag (billow), m " = engineering straiń = ef ciency of specular re ectivity » = normalized catenary sag, ± c =b N ½ = structural surface density (structural mass per area), kg/m 2 ¾ = lm skin stress, Pa, kPa, psi

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Proposed for the high performance vibration testing of free-flying systems is the Marionette paradigm, a mechanically simple passive gravity compensation scheme characterized by low mass, little interference with specimen response, high imperfection tolerance, and compatibility with up to medium scale specimen kinematics. An introduction to this concept, theory, features, and some practicalities, is offered. The need for and the potential of system optimization are discussed and illustrated. Possible means to generalize the basic concept to adaptive specimen geometries or to the simulation of nonuniform inertial conditions are also discussed. Hardware and numerical illustrations are presented. Nomenclature d = diameter dz = vertical displacement E, = Young's modulus and Poisson's ratio e = fulcrum offset e x , e z = fulcrum offset components in directions x, z h = fly beam arm tip vertical displacement K = geometric nonlinear stiffness against beam tilt L = fly beam span: the distance between arm endpoints M = moment m = mass m= direct mass overhead support structure mass/mass supported r = fly beam arm length S, S i = load tree top and anchor point forces W, w = weight = fly beam arm ratio r 1 =r 2 = density (specific mass) = Force ratio: ratio of fly beam arm loads S 1 =S 2 Subscripts 1, 2 = association with one or the other fly beam arm