초록 ▼

A golf club includes an electroactive assembly attached to the club and electrically tuned to capture energy from one or more vibrational modes with high efficiency. More generally, a sports implement includes an electroactive element, such as a piezoceramic sheet attached to the implement, and a ci

A golf club includes an electroactive assembly attached to the club and electrically tuned to capture energy from one or more vibrational modes with high efficiency. More generally, a sports implement includes an electroactive element, such as a piezoceramic sheet attached to the implement, and a circuit attached to the electroactive element. The circuit may be a shunt, or may include processing such as amplification and phase control to apply a driving signal which may compensate for strain sensed in the implement, or may simply alter the stiffness to affect performance. The electroactive element is located in a region of high strain to apply damping, and may include plural subassemblies mounted to capture energy in different planes, or to capture an asymmetric strain distribution while maintaining structural symmetry. In a ski the element captures between about one and five percent of the strain energy of the ski. The region of high strain may be found by modeling mechanics of the sports implement, or may be located by empirically mapping the strain distribution which occurs during use of the implement. In other embodiments, the electroactive elements may remove resonances, adapt performance to different situations, or enhance handling or comfort of the implement. Other embodiments include striking implements intended to hit a ball or object in play, such as mallets, bats and tennis racquets, wherein the strain elements may alter the performance, feel or comfort of the implement. The electroactive elements may be configured in sets to capture energy in different modes, and/or energy distributed along different directions.

대표청구항 ▼

[What is claimed is:] [1.]a body having an extent and a contact surface which is subject to stimulation such that at least a portion of the body vibrates with a distribution of strain energy that includes a region of strain; andan electroactive assembly comprising:an electroactive strain element for

[What is claimed is:] [1.]a body having an extent and a contact surface which is subject to stimulation such that at least a portion of the body vibrates with a distribution of strain energy that includes a region of strain; andan electroactive assembly comprising:an electroactive strain element for transducing electrical energy and mechanical strain energy; anda circuit across said assembly configured to dissipate said electrical energy and damp vibration of the body,wherein said electroactive assembly is attached to said body in said region of strain such that said electroactive assembly is attached on a shaft and away from the contact surface.