Abstract:
In general, a computing device disposed in a cardio exercise machine receives data related to a fitness level of a user. The computing device selects a workout program based at least in part on the data. The operations of the cardio exercise machine are controlled based at least in part on the workout program. The computing device generates visual feedback based on at least one of the user's operation of the cardio exercise machine and the selected workout program measured against performance criteria.
Abstract:
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.
Abstract:
A hybrid actuator includes strain actuated elements that displace fluid to move a piston, with the elements forming a fluid housing, and being oriented and actuated to optimize force, stroke or bandwidth. In one preferred embodiment the elements are cylinders enclosing the fluid, with radial and axial components of strain-induced dimensional change adding together to enhance displacement. In another preferred embodiment, piezo bender elements produce large stroke, high bandwidth movements. Strokes of up to fifty percent of actuator length, and bandwidths above 500 Hz are achieved in light weight electrically actuated devices free of external piping or hydraulics. The actuator is readily integrated into a gate valve, sub-woofer, or other driven device.
Abstract:
A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate, machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required. The actuator assembly can be manufactured in quantity, to provide a versatile actuator with uniform mechanical and actuation characteristics, that introduces negligible mass loading to the workpiece. The cards themselves may be arranged as independent mechanical actuators, rather than strain-transfer actuators, in which the induced strain changes the position of the card. Various arrangements of pinned or cantilevered cards may act as a pusher, bender or other motive actuator, and structures such as powered bellows may be formed directly by folding one or more suitably patterned cards.
Abstract:
Described is a circuit arrangement for detection of a tone whose presence indicates insertion of a headphone plug into a jack. The circuit includes a receptacle having contacts configured to receive a plug inserted into the receptacle, a current sense circuit, an amplifier coupled to the current sense circuit and a band pass filter coupled to an output of the amplifier, the band pass filter configured to pass a signal having a frequency in a range of about 2 Hz to 20 Hz. Circuitry converts the passed signal into a digital signal to provide an input signal to a controller to indicate that a headphone plug was inserted into the receptacle.
Abstract:
In general, a computing device disposed in a cardio exercise machine receives data related to a fitness level of a user. The computing device selects a workout program based at least in part on the data. The operations of the cardio exercise machine are controlled based at least in part on the workout program. The computing device generates visual feedback based on at least one of the user's operation of the cardio exercise machine and the selected workout program measured against performance criteria.
Abstract:
A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required. The actuator assembly can be manufactured in quantity, to provide a versatile actuator with uniform mechanical and actuation characteristics, that introduces negligible mass loading to the workpiece. The cards themselves may be arranged as independent mechanical actuators, rather tan strain-transfer actuators, in which the induced strain changes the position of the card. Various arrangements of pinned or cantilevered cards may act as a pusher, bender or other motive actuator, and structures such as powered bellows may be formed directly by folding one or more suitably patterned cards.
Abstract:
A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece, device, substrate machine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required. The actuator assembly can be manufactured in quantity, to provide a versatile actuator with uniform mechanical and actuation characteristics, that introduces negligible mass loading to the workpiece. The cards themselves may be arranged as independent mechanical actuators, rather than strain-transfer actuators, in which the induced strain changes the position of the card. Various arrangements of pinned or cantilevered cards may act as a pusher, bender or other motive actuator, and structures such as powered bellows may be formed directly by folding one or more suitably patterned cards.
Abstract:
A recreational board such as a snowboard incorporates strain transducers to damp a plate resonance of the board. The strain transducers are preferably located around a peripheral region to capture strain energy affecting control edges, for example steering control edges at the front and/or rear of the board. Electrical energy from the transducers is shunted to damp a targeted resonance. In a preferred embodiment the strain transducers cover a region of the snowboard adjacent one surface and extending along the forward periphery, preferably at both inside and outside edges, and are shunted with a resonant shunt tuned to a torsional or torsion-like mode of the board that is excited during steering maneuvers. The transducers may be fabricated as preassembled sheets or may be formed in the snowboard during the assembly process using sheets of piezoceramic material, or using piezo fiber or other composite constructions. The strain material may be positioned to preferentially shift or damp one resonance mode, and/or it may be arranged to exert a directional effect or anisotropic control authority. A passively operated embodiment employs a simple resistive shunt to enhance control of strain energy at the frequency of a resonant mode of the snowboard. Damping of that mode reduces chatter of the steering edges in use. The strain elements may be used in conjunction with viscoelastic or other damping mechanisms to tailor the overall level of mechanical control and limit the allowed excitations of the board.
Abstract:
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.