Abstract: An active vibration isolation system for isolating a suspended platform from vibration input to the vibration isolation system base includes an exoskeleton, a rotary actuator, and a drive mechanism separate from the exoskeleton for providing force output from the rotary actuator to the suspended plant. The rotary actuator may include inner and outer rotors which rotate relative to each other. The rotary actuator may be free to translate relative to the vibration isolation system base and the suspended platform, and both the inner and outer rotors may be free to rotate relative to the exoskeleton.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever coupling the oscillatory force source to the acoustic diaphragm, and a pivot coupled to the lever such that the lever moves in an arcuate path about the pivot when the oscillatory force source applies a force to the lever. The pivot includes at least one torsion bushing. The at least one torsion bushing includes a first member, a second member coupled to the lever and movable relative to the first member, and an elastomeric member coupling the first member to the second member. Either the first member or the second member is coupled to and moves with the lever. An outer surface of the elastomeric member is coupled to the second member via mechanical compression.

Abstract: An apparatus includes at least one load and a plurality of armatures, each including a permanent magnet, which are coupled to the at least one load to cause the at least one load to move. The apparatus also includes a common stator that defines an air gap within which the plurality of armatures is disposed. The common stator is configured for creating magnetic flux across the air gap for the armatures to interact with, thereby to drive motion of the at least one load.

Abstract: An apparatus includes a load, a lever that is coupled to the load, and an electric motor that is coupled to the lever for driving the lever in oscillatory, rotary motion about a pivot axis. The electric motor includes an armature and a stator. The armature is coupled to the lever and includes a permanent magnet. The stator defines an air gap within which the armature is disposed. The stator is configured for creating magnetic flux across the air gap for the permanent magnet to interact with, thereby to drive motion of the load. The electric motor is configured such that substantially no detent forces (a/k/a cogging forces) are generated between the stator and the permanent magnet as the lever is driven by the motor.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever coupling the oscillatory force source to the acoustic diaphragm, and a pivot coupled to the lever such that the lever moves in an arcuate path about the pivot when the oscillatory force source applies a force to the lever. The pivot includes at least one torsion bushing. The at least one torsion bushing includes a first member, a second member coupled to the lever and movable relative to the first member, and an elastomeric member coupling the first member to the second member. Either the first member or the second member is coupled to and moves with the lever. An outer surface of the elastomeric member is coupled to the second member via mechanical compression.

Abstract: An apparatus includes a load and a first armature. A first lever mechanically couples the first armature and the load. Motion of the first armature causes the first lever to pivot about a first pivot axis. The apparatus also includes a second armature and a second lever that mechanically couples the second armature and the load. Motion of the second armature causes the second lever to pivot about a second pivot axis. At least one stator is provided for creating magnetic flux for the first and second armatures to interact with, thereby to drive motion of the load. The apparatus also includes a coupling mechanism that couples the first lever and the second lever. The coupling mechanism is arranged to encourage common mode oscillation of the first and second levers and inhibit differential mode oscillation of the first and second levers, thereby to inhibit rocking of the load.

Abstract: A loudspeaker includes an acoustic diaphragm, a lever, and an oscillatory force source for driving the lever in oscillatory, rotary motion about a pivot axis. The loudspeaker also includes a connector that couples the lever to the acoustic diaphragm. The connector includes a first rotary joint that defines a first rotary axis that is fixedly attached to the acoustic diaphragm, a second rotary joint that defines a second rotary axis that is fixedly attached to the lever, and a linkage coupling the first and second rotary joints. The connector allows for rotational and translational movement of the lever and the diaphragm relative to each other.

Abstract: An electro-acoustic driver including an acoustic waveguide includes an enclosure, an acoustic transmission line formed within the enclosure, and a plurality of acoustic transducers contained within the enclosure and disposed along a length of the acoustic transmission line. Each acoustic transducer is configured to emit acoustic energy directly into the acoustic transmission line at two separated locations along the length of the acoustic transmission line.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever coupling the oscillatory force source to the acoustic diaphragm, and a pivot coupled to the lever such that the lever moves in an arcuate path about the pivot when the oscillatory force source applies a force to the lever. The pivot includes at least one torsion bushing. The at least one torsion bushing includes a first member, a second member coupled to the lever and movable relative to the first member, and an elastomeric member coupling the first member to the second member.

Abstract: An active vibration isolation system for isolating a suspended platform from vibration input to the vibration isolation system base includes an exoskeleton which supports the suspended platform relative to the base. The exoskeleton includes first and second scissors mechanisms with main links of unequal length. The main links pass through a parallel condition as the suspended platform moves over its intended range of travel relative to the base. The vibration isolation system may include a rotary actuator and a drive mechanism separate from the exoskeleton for providing force output from the rotary actuator to the suspended platform. The rotary actuator may include inner and outer rotors which rotate relative to each other and may be free to rotate relative to the exoskeleton. The rotary actuator may be free to translate relative to the vibration isolation system base and the suspended platform.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever that couples the oscillatory force source to the acoustic diaphragm, and a pivot that is coupled to the lever such that the lever pivots about a pivot axis when the oscillatory force source applies a force to the lever. The pivot includes a pair of rotational joints which are spaced apart to allow the diaphragm to pass therebetween as the lever pivots about the pivot axis.

Abstract: An apparatus includes a load, a lever that is coupled to the load, and an electric motor that is coupled to the lever for driving the lever in oscillatory, rotary motion about a pivot axis. The electric motor includes an armature and a stator. The armature is coupled to the lever and includes a permanent magnet. The stator defines an air gap within which the armature is disposed. The stator is configured for creating magnetic flux across the air gap for the permanent magnet to interact with, thereby to drive motion of the load. The electric motor is configured such that substantially no detent forces (a/k/a cogging forces) are generated between the stator and the permanent magnet as the lever is driven by the motor.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever that couples the oscillatory force source to the acoustic diaphragm, and a pivot that is coupled to the lever such that the lever pivots about a pivot axis when the oscillatory force source applies a force to the lever. The pivot includes a pair of rotational joints which are spaced apart to allow the diaphragm to pass therebetween as the lever pivots about the pivot axis.

Abstract: A loudspeaker includes an acoustic diaphragm, an oscillatory force source, a lever coupling the oscillatory force source to the acoustic diaphragm, and a pivot coupled to the lever such that the lever moves in an arcuate path about the pivot when the oscillatory force source applies a force to the lever. The pivot includes at least one torsion bushing. The at least one torsion bushing includes a first member, a second member coupled to the lever and movable relative to the first member, and an elastomeric member coupling the first member to the second member.

Abstract: A loudspeaker includes an acoustic diaphragm, a lever, and an oscillatory force source for driving the lever in oscillatory, rotary motion about a pivot axis. The loudspeaker also includes a connector that couples the lever to the acoustic diaphragm. The connector includes a first rotary joint that defines a first rotary axis that is fixedly attached to the acoustic diaphragm, a second rotary joint that defines a second rotary axis that is fixedly attached to the lever, and a linkage coupling the first and second rotary joints. The connector allows for rotational and translational movement of the lever and the diaphragm relative to each other.

Abstract: An apparatus includes a load and a first armature. A first lever mechanically couples the first armature and the load. Motion of the first armature causes the first lever to pivot about a first pivot axis. The apparatus also includes a second armature and a second lever that mechanically couples the second armature and the load. Motion of the second armature causes the second lever to pivot about a second pivot axis. At least one stator is provided for creating magnetic flux for the first and second armatures to interact with, thereby to drive motion of the load. The apparatus also includes a coupling mechanism that couples the first lever and the second lever. The coupling mechanism is arranged to encourage common mode oscillation of the first and second levers and inhibit differential mode oscillation of the first and second levers, thereby to inhibit rocking of the load.

Abstract: An electro-acoustic driver including an acoustic waveguide includes an enclosure, an acoustic transmission line formed within the enclosure, and a plurality of acoustic transducers contained within the enclosure and disposed along a length of the acoustic transmission line. Each acoustic transducer is configured to emit acoustic energy directly into the acoustic transmission line at two separated locations along the length of the acoustic transmission line.

Abstract: An active vibration isolation system for isolating a suspended platform from vibration input to the vibration isolation system base includes an exoskeleton, a rotary actuator, and a drive mechanism separate from the exoskeleton for providing force output from the rotary actuator to the suspended plant. The rotary actuator may include inner and outer rotors which rotate relative to each other. The rotary actuator may be free to translate relative to the vibration isolation system base and the suspended platform, and both the inner and outer rotors may be free to rotate relative to the exoskeleton.

Abstract: An active vibration isolation system for isolating a suspended platform from vibration input to the vibration isolation system base includes an exoskeleton which supports the suspended platform relative to the base. The exoskeleton includes first and second scissors mechanisms with main links of unequal length. The main links pass through a parallel condition as the suspended platform moves over its intended range of travel relative to the base. The vibration isolation system may include a rotary actuator and a drive mechanism separate from the exoskeleton for providing force output from the rotary actuator to the suspended platform. The rotary actuator may include inner and outer rotors which rotate relative to each other and may be free to rotate relative to the exoskeleton. The rotary actuator may be free to translate relative to the vibration isolation system base and the suspended platform.

Abstract: An apparatus includes at least one load and a plurality of armatures, each including a permanent magnet, which are coupled to the at least one load to cause the at least one load to move. The apparatus also includes a common stator that defines an air gap within which the plurality of armatures is disposed. The common stator is configured for creating magnetic flux across the air gap for the armatures to interact with, thereby to drive motion of the at least one load.