Abstract: A compaction assembly comprising a lobed roller and a draw frame; and the operation thereof. A pair of composite links interconnects the roller and frame, each being pivotally connected to the frame and comprising at least two constituent links pivotally interconnected, all of said pivotal connections having lateral axes. Bearing means on each composite link carries the roller which extends therebetween. The composite links act as guide means constraining and guiding rolling of the roller. The bearing means are mounted to be independently pivotable about two or more axes relative to the draw frame and so that the roller axis has vertical free movement subject to gravity. Bias means biasses constituent links of the composite links into positions inclined to each other and allows the roller axis resiliently damped free movement relative to the frame in opposite directions along the direction of rolling.