We present a novel armature structure for 3D shapes, called SBall short for ‘skeletal balls’, which includes two parts: a curve skeleton and incident balls. This structure is based on an approximation skeleton which is homotopy equivalent to the shape. Each ball in the structure connects a skeletal joint and an interior region of the shape. The boundary vertices on the shape surface are attached onto the SBall using the power diagram of the ball set. A bilateral filtering algorithm and a variational segmentation algorithm are proposed to enhance the quality of SBall. Finally, applications of this structure are discussed.