Abstract: An "isoharmonic" sports bat, for example a baseball bat or cricket bat, includes a hitting surface for impact with a ball, wherein the duration of a half cycle of a selected mode of vibration of the hitting surface when in contact with the ball is approximately equal to the contact time between the hitting surface and the ball during an average impact. This allows the vibrational energy of the bat to be returned efficiently to the ball, which improves the coefficient of restitution, and the peak contact force between the bat and the ball may be reduced. The hitting surface may be formed by a plate attached to the bat.

Abstract: A laser cutter for cutting textile or leather clothing material adhered on a stiff tacky backing sheet includes a laser which produces a laser beam, a guide head for reflecting and focusing the laser beam onto the sheet-backed clothing material, and an optical sensor mounted on the guide head for recognizing the shape or a pattern marked on the material. The material is supported by an idler roller. Under the control of a computer, a pair of bi-directionally driven pinch rollers move the material back and forth across the idler roller in synchronism with movement of the guide head transversely across the material. The computer alternately activates and controls the optical sensor or the laser. In an optical scanning mode, under control of the computer, the material is scanned to create in the computer memory a model of the desired pattern to be cut in the clothing material, and a desired cutting path matched to the shape of, or pattern on, the clothing material.

Abstract: A process for reproducing a design, especially a fabric design comprising an embroidered applique element stitched to a base fabric material, comprises the sequential steps of analyzing the design to derive data for use as stitch command data by an embroidery machine, and as cutting command data by a cutting machine, cutting out an applique element from a sheet material in accordance with the cutting command data, transferring the cut-out applique element to the base material and stitching the applique element to a base material in accordance with the stitch command data. The invention provides a far quicker, more accurate and neater embroidered applique fabric than prior semi-manual techniques.