Abstract: This invention concerns devices, systems, and methods to induce motion in cantilevers for actuation and sensing applications. Motion is induced by applying current to a ferromagnetic, magnetostrictive cantilever subject to bending stress, and hence strain (deflection), having both elastic and magnetoelastic components. The applied current creates a magnetic field that reorients the magnetoelastic strain component, changing the total strain and thus the total deflection. Changing deflection can be harnessed for actuation or work. Moreover, considering both static and dynamic deflection, measureable parameters that are associated with beam deflection, vibration frequency, and/or amplitude can be measured.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: A new type of magnetoelastic device for sensing force is described. It comprises of two elements: a circumferentially magnetized member comprised of magnetoelastically active material mounted as a beam and loaded by the force to be sensed, and a magnetic field sensor mounted at or near the member's surface, preferentially at or near a longitudinal location where the bending moment is maximum and at a circumferential location where the bending stress is zero. Flexural loading causes a variation of the circumferential magnetization with angular position. This variation is the source of free poles, the field from which is a measure of the applied force. Testing demonstrates that the field intensity is a linear analog of the experienced bending stress over a significant range of applied push and pull forces.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a magnetic drag force between a ferromagnetic sample that is or has been in motion relative to one or more measurement magnets are described. Such sensors include at least one measurement magnet and a sensing element operably associated therewith, such that upon or after exposure of the measurement magnet(s) to a ferromagnetic sample in motion relative thereto, the sensor can sense the drag force, if any, or changes therein, experienced by the measurement magnet. Devices for detecting and/or measuring magnetic drag force that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a magnetic drag force between a ferromagnetic sample that is or has been in motion relative to one or more measurement magnets are described. Such sensors include at least one measurement magnet and a sensing element operably associated therewith, such that upon or after exposure of the measurement magnet(s) to a ferromagnetic sample in motion relative thereto, the sensor can sense the drag force, if any, or changes therein, experienced by the measurement magnet. Devices for detecting and/or measuring magnetic drag force that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: Sensors for outputting signals indicative of a rate of change of torque experienced by a magnetized member in response to a change in torque experienced by the member are described. Such sensors include at least one sense element capable of detecting a change in a magnetic parameter of a magnetized region of the member positioned proximate to the sense element in response to a change in torque applied to the member. Devices for detecting and/or measuring rates of changes in or of torque that employ one or more of these sensors are also described, as are various applications for such devices.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member, comprising, a first magnetoelstically active region in the member, the region being ferromagnetic, magnetostrictive magnetically polarized in a single circumferential direction and possessing sufficient magnetic anisotropy to return the magnetization in the region to the single circumferential direction when the applied torque is reduced to zero, whereby the ferromagnetic, magnetostrictive region produces a magnetic field varying with the torque. Magnetic field sensors are mounted proximate to the ferromagnetic, magnetostrictive region to sense the magnetic field at the sensors and provide the output signal in response thereto.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member includes a ferromagnetic, magnetostrictive, magnetoelastically active region on or in the member, the region begin proportionally subjected to the torque applied to the member. The region is endowed with an effective uniaxial magnetic anisotropy having the circumferential direction as the easy axis and is magnetically polarized in a single circumferential direction. When torque is applied to the member, the magnetoelastically active region produces a magnetic field varying with the torque, which field is sensed by magnetic field sensors arranged proximate the region.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member, comprising, a first magnetoelstically active region in the member, the region being ferromagnetic, magnetostrictive magnetically polarized in a single circumferential direction and possessing sufficient magnetic anisotropy to return the magnetization in the region to the single circumferential direction when the applied torque is reduced to zero, whereby the ferromagnetic, magnetostrictive region produces a magnetic field varying with the torque. Magnetic field sensors are mounted proximate to the ferromagnetic, magnetostrictive region to sense the magnetic field at the sensors and provide the output signal in response thereto.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member includes a ferromagnetic, magnetostrictive, magnetoelastically active region on or in the member, the region begin proportionally subjected to the torque applied to the member. The region is endowed with an effective uniaxial magnetic anisotropy having the circumferential direction as the easy axis and is magnetically polarized in a single circumferential direction. When torque is applied to the member, the magnetoelastically active region produces a magnetic field varying with the torque, which field is sensed by magnetic field sensors arranged proximate the region.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member about an axially extending axis of the member, comprising, a first ferromagnetic, magnetostrictive region in the member, the region being magnetically polarized in a single circumferential direction and possessing sufficient magnetic anisotropy to return the magnetization in the region, following the application of torque to the member, to the single circumferential direction when the applied torque is reduced to zero, whereby the ferromagnetic, magnetostrictive region produces a magnetic field varying with the torque. Magnetic field sensors are mounted proximate to the ferromagnetic, magnetostrictive region and oriented with respect thereto to sense the magnetic field at the sensors and provide the output signal in response thereto.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member about an axially extending axis of the member, comprising, a first magnetoelastically active region in the member, the region being magnetically polarized in a single circumferential direction and possessing sufficient magnetic anisotropy to return the magnetization in the region, following the application of torque to the member, to the single cirumferential direction when the applied torque is reduced to zero, whereby the magnetoelastically active region produces a magnetic field varying with the torque. Magnetic field sensors are mounted proximate to the magnetoelastically active region and oriented with respect thereto to sense the magnitude of the magnetic field at the sensors and provide the output signal in response thereto.

Abstract: A magnetoelastic torque sensor for providing an output signal indicative of the torque applied to a member about an axially extending axis of the member, comprising, a member which is unitary and of generally homogeneous chemical composition, the member comprising separate magnetically active and magnetically substantially passive regions. A first magnetoelastically active region in the member is magnetically polarized in a single circumferential direction and possesses sufficient magnetic anisotropy to return the magnetization in the region, following the application of torque to the member, to the single circumferential direction when the applied torque is reduced to zero, whereby the magnetoelastically active region produces a magnetic field varying with the torque. Magnetic field sensors are mounted proximate to the magnetoelastically active region and oriented with respect thereto to sense the magnitude of the magnetic field at the sensors and provide the output signal in response thereto.

Abstract: A torque sensor comprises a magnetoelastically active element, and a magnetic sensor, such as a Hall effect sensor, responsive to the field of the magnetoelastically active portion. In the preferred embodiment, the magnetoelastically active portion comprises a ring of material endowed with an effective uniaxial magnetic anisotropy such that the circumferential direction is the easy axis, and magnetically polarized in a substantially circumferential direction. The ring is attached to the torqued member, such as a rotating shaft, so that application of a torque to the shaft is transmitted to the ring. The torque on the ring reorients the circumferential magnetic orientation of the ring, producing a helical magnetic orientation having both circumferential and axial components. A magnetic field vector sensor is mounted on a flux collector in a fixed position relative to the ring and oriented so that it responds to the field arising from the axial component of the magnetization within the ring.

Abstract: A torque sensor for providing an output signal indicative of the torque applied to a rotating torqued member comprises a magnetoelastically active element for producing a magnetic field varying with the applied torque and a field modulating means for modulating the magnetic field in a periodic manner which is indicative of the speed of member rotation. A magnetic field vector sensor, such as a Hall effect sensor, senses the amplitude of the modulated field for providing an output signal which is linearly indicative of the torque applied to the rotating member. The field modulating means preferably comprises at least one ring having some uniformly spaced salient feature, such as gear-like teeth, around the periphery thereof. In one embodiment, the magnetoelastically active element comprises a ring of material endowed with an effective uniaxial magnetic anisotropy such that the circumferential direction is the easy axis, and magnetically polarized in a substantially circumferential direction.

Abstract: A power sensor for providing an output signal indicative of the power transmitted by a rotating torqued member comprises a magnetoelastically active element for producing a magnetic field varying with the applied torque and a field modulating means for modulating the magnetic field in a periodic manner which is indicative of the speed of member rotation. A magnetic field vector sensor in the form of a coil senses the amplitude of the time rate of change of the modulated field for providing an output signal which is linearly indicative of the power transmitted by the rotating member. The field modulating means preferably comprises at least one ring having some uniformly spaced salient feature, such as gear-like teeth, around the periphery thereof.