The framed n-discs operad f D n is studied as semidirect product of SO(n) and the little n-discs operad. Our equivariant recognition principle says that a grouplike space acted on by f D n is equivalent to the n-fold loop space on an SO(n)-space. Examples of f D 2 -spaces are nerves of ribbon braided monoidal categories. We compute the rational homology of f D n , which produces higher Batalin-Vilkovisky algebra structures for n even. We study quadratic duality for semidirect product operads

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... compute the double loop space homology of a manifold as BV-algebra. †