Patent Application
20100050788
The present disclosure relates generally to the measurement of system parameters and, more specifically, to the nanoscale measurement of force, torque and acceleration.
Nanotechnology is an important field of endeavor that provides materials and devices in nanoscale that may be used in a wide variety of applications. In the implementation of nanoscale materials and devices, it may be useful to sense and measure various parameters, such as force, torque and acceleration. Further, it may be advantageous to sense and measure parameters with sensitivity such that small magnitudes may be measurable.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the components of the present disclosure, as generally described herein, and illustrated in the figures, may be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and made part of this disclosure.
In the following description, various embodiments will be disclosed. However, it will be apparent to those skilled in the art that the embodiments may be practiced with all or only some of the disclosed subject matter. For purposes of explanation, specific numbers and/or configurations are set forth in order to provide a thorough understanding of the embodiments. However, it will also be apparent to one skilled in the art that the embodiments may be practiced without one or more of the specific details, or with other approaches and/or components. In other instances, well-known structures and/or operations are not shown or described in detail to avoid obscuring the embodiments. Furthermore, it is understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, and designed in a wide variety of different configurations, all of which are explicitly contemplated and made part of this disclosure.
References throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner. Various operations may be described as multiple discrete steps in turn, in a manner that is most helpful in understanding the claimed subject matter. However, the order of description should not be construed as to imply that these operations are necessarily order dependent.
This disclosure is drawn, inter alia, to nanoscale measurement devices and apparatuses, methods for measuring nanoscale forces and torques, and related nanoscale systems. The nanoscale measurement device may be considered a force transducer, a torque transducer, or an accelerometer.
In an embodiment, a nanoscale measurement device may include a first plurality of nanoparticles coupled to a substrate surface by optional couplers. The device may also include a second plurality of nanoparticles coupled to a second substrate surface by optional couplers. The first plurality of nanoparticles may be spaced such that they electrically contact each other or such that they have small gaps that may be tunneled by electrons. In either case, electrical continuity across the first plurality of nanoparticles may be provided. The second plurality of nanoparticles may be similarly situated to provide electrical continuity across the second plurality of nanoparticles. The first and second pluralities of nanoparticles may face each other and, in the rest state of the device, be held apart by pillars disposed between the surfaces of the first and second substrates. Electrical contact to the first and second pluralities of nanoparticles may be made by electrodes, such that one or more electrodes may be incorporated to provide an electrical circuit along each of the first and second pluralities of nanoparticles. In one example, three electrodes may be used with one electrode contacting the first plurality of nanoparticles, a second electrode contacting the second plurality of nanoparticles, and a third electrode contacting the first and second plurality of nanoparticles. In another example, four electrodes may be used with two electrodes contacting the first plurality of nanoparticles at opposite ends of the device and two other electrodes contacting the second plurality of nanoparticles at the opposite ends of the device. The electrodes may be coupled to a sensing device that may provide an electrical voltage or current in order to measure characteristic resistances of the nanoscale measurement device. Accordingly, the device may monitor changes in electrical properties of at least one of the first and second pluralities of the nanoparticles, changes in electrical interactions between the first and second pluralities of the nanoparticles, or the like.
In operation, a force may be applied to a surface of one or both of the substrates and the device may begin to deform such that the substrates may bow. The sensing device may be able to detect the deformation by sensing a change in the measured electrical resistances. In an embodiment, the change in resistance may be due to changes in the positions of the nanoparticles as compared to the rest state in one or both of the first and second pluralities of nanoparticles. For example, the first or second plurality of nanoparticles may tend to splay apart under the applied force or the first or second plurality of nanoparticles may tend to compact. Those changes may cause a change in the resistances sensed by the sensing device, which may be correlated to a measurement of force, torque or acceleration. In another example, the device may be configured such that some of the first plurality of nanoparticles contact some of the second plurality of nanoparticles upon the application of a force. The number of contacting particles may depend on the amount of force applied. The contact between the particles may cause a change in the characteristic resistances that may be sensed and correlated to a force, torque or acceleration measurement.
In another embodiment, a light emitter and a detector may be provided. The light source may irradiate the device and the detector may receive resultant light rays. The light rays may be transmitted through the device or the light rays may be reflected off the device. In either event, the resultant light rays may be monitored for, for example, a polarization change, an intensity change or a diffraction pattern. The monitored parameter may relate to a change in an optical property of the device due to an above described deformation of the device, which may be correlated to a force, torque or acceleration measurement. In some examples, the light source and the detector may be used without the electrodes and electrical sensor, and in other examples, they may be used with the electrodes and a sensor.
Turning now to
Further, nanoparticles 115 and nanoparticles 130 may have electrical or optical characteristics that may be probed via the electrodes. When a force is applied to measurement device 100, the configuration of the nanoparticles may change such that the electrical or optical characteristics may change. Those changes may be correlated to determine a measured force, for example, of the force applied to the device. Since measurement device 100 may include two or more layers of nanoparticles, it may be considered a multilayered nanoparticle device. Although illustrated in a cross-section or side view for ease of understanding, measurement device 100 may be an enclosed device including a sealant around the edge of the device and between substrate 120 and substrate 105.
Referring now to
Sensing device 210 may electrically probe measurement device 100 using the connectors and electrodes. In one example, sensing device 210 may include a voltage source and a current measuring device. In another example, sensing device 210 may include a current source and a voltage measuring device. Sensing device 210 may include multiple voltage sources and/or current sources. Sensing device 210 may also include a processor, a memory, and related circuitry that may provide control over a sensing pattern and memory for data storage. Using the provided voltage and measured current (or provided current and measured voltage), a characteristic resistance of the measurement device may be determined. As discussed, connectors 255, 265 may couple to one set of nanoparticles while connectors 250, 260 may couple to another set of nanoparticles. Connectors 250, 255 may be coupled to one side of a voltage source and connectors 260, 265 coupled to another side of the voltage source, such that a parallel circuit may be provided. By measuring the resistance of the parallel circuit a sensitive measurement of a force on the device may be obtained.
With reference to
Such changes in orientation may cause change in the resistances of the device. For example, a closed parallel circuit using connectors 250, 255 coupled to one end of a voltage source and connectors 260, 265 (please refer to
As shown in
As discussed, electrical conductivity between the nanoparticles may be provided by electron tunneling across gaps or by the nanoparticles being densely enough spaced to provide direct electrical connection. Although
Referring again to
Nanoparticles 115 may be coupled to surface 170 of substrate 105 by optional couplers 110, and nanoparticles 130 may be coupled to surface 175 of substrate 120 by optional couplers 125. Alternatively, nanoparticles 115, nanoparticles 130, or both may be directly mounted to their respective substrates. Nanoparticles 115 and nanoparticles 130 may be any suitable size. In some examples, they may have diameters in the range of approximately 100 to 2,500 nm. In other examples, they may have diameters in the range of approximately 1 to 100 nm. Nanoparticles 115, 130 may include a variety of conductive materials including, but not limited to, copper, silver, gold, nickel, palladium, platinum, tin, lead, aluminum, and alloys thereof. Different materials may be used among nanoparticles 115 or nanoparticles 130 such that the nanoparticles are not necessarily uniform across their entirety. For example, materials of different conductivities may be used across the device in some applications. Nanoparticles 115 and nanoparticles 130 may include uniform conductive materials or they may include nonconductive nanoparticles with conductive coatings. Nanoparticles 115 and nanoparticles 130 may include the same materials or they may include different materials.
Nanoparticles 115 may be configured to provide electrical continuity among nanoparticles 115, and nanoparticles 130 may be similarly configured to provide electrical continuity among nanoparticles 130. In some examples, the electrical continuity may be provided by the nanoparticles being spaced densely enough to provide direct electrical contact. In other examples, there may be gaps between the nanoparticles that may be quantum mechanically tunneled by electrons such that electrical continuity may be provided. Nanoparticles 115 and nanoparticles 130 may be configured as a conductive tightly packed array or mesh of nanoparticles. Nanoparticles 115, 130 may be evenly or nearly evenly spaced throughout the device as one mesh. Alternatively, the nanoparticles may be spaced at different pitches at different locations of the device. Further, two or more conductive meshes of nanoparticles may be used. The multiple nanoparticle meshes may be provided in series or parallel electrically.
Optional couplers 110, 125 may include a variety of rigid, semirigid or flexible materials, such as, but not limited to, long chain molecules, molecular assemblies of high aspect ratios, nanotubes, lipids, DNA, RNA, and proteins. Couplers 110, 125 may include insulating materials so as not to provide a conduction path. In an embodiment, couplers 110, 125 may be at least partially electrically conductive and couplers 110, 125 may form an additional path or additional paths for electrons, such that such couplers 110, 125 may increase the current when a torque is applied, thereby enhancing the sensitivity of device 100. Couplers 110 may include the same material as substrate 105 and/or couplers 125 may include the same material as substrate 120, such as the sample materials listed above. Couplers 110 may be of approximately the same length as couplers 125 or their lengths may be different. For example, couplers 110 may be longer than couplers 125. Couplers 110 and couplers 125 may be of any suitable length, such as, but not limited to, approximately 10 to 2,000 nm. A single coupler may be included for each nanoparticle or multiple couplers, such as, but not limited to, 2 to 5 couplers, may be provided for each nanoparticle.
Further, couplers 110 may have approximately the same lengths throughout the device or their lengths may vary, such that in side-view profile they have, for example, a sloped shape. That is, on one end of the device, couplers 110 may be shorter or longer than on another end of the device. Other profile shapes may be used, such as, for example, curved shapes. Typically, couplers 110 and couplers 125 may have approximately the same profile shapes such that distance between immediately adjacent nanoparticles 115 and nanoparticles 130 may be approximately constant throughout the device. For example, in
As shown, pillars 135, 140 may be disposed between surface 170 and surface 175 such that nanoparticles 115 and nanoparticles 130 may be separated by a distance. Pillars 135, 140 may be partially elastic such that they compress to a shorter profile when the measurement device is deformed or they may be rigid such that they maintain their shape when the device is deformed. In an example, pillars 135, 140 may be rigid such that pillars 135, 140 may be displaced angularly in response to a force or torque and nanoparticles 115, 130 may move closer to each other.
Pillars 135, 140 may take on a variety of configurations. As in the illustrated example, pillars 135, 140 may be provided outside or near the periphery of the nanoparticles. In other examples, an additional pillar or pillars may be provided among the nanoparticles, such as at or near the center of the device. In another example, a pillar or several pillars may be provided among the nanoparticles without pillars being provided outside or near the periphery of the device.
The pillars may include a variety of materials including, but not limited to, long chain molecules, crooked long chain molecules, molecular assemblies of high aspect ratios, nanotubes, lipids, DNA, RNA, and proteins. In some examples, the pillars may include the same material as the substrate materials, as listed above. The pillar materials may maintain the integrity of the device upon repeated applications of force on the device. Pillar 135 may be the same material as pillar 140 or they may be different materials. Further, the pillars may be fixedly coupled to one of the substrates or both substrates. For example, pillar 135 may be fixedly connected to surface 170 of substrate 105 and may be butted against surface 175 of substrate 120. Alternatively, pillar 135 may be fixedly connected to both surface 170 and surface 175.
As shown, nanoparticles 115 may be contacted at one end of the device by electrode 155 and at another end of the device by electrode 165. Similarly, nanoparticles 130 may be contacted at one end of the device by electrode 150 and at another end of the device by electrode 160. Electrodes 150, 155, 160, 165 may include a variety of conductive materials including, but not limited to copper, silver, gold, nickel, palladium, platinum, tin, lead, aluminum, tungsten, alloys of those materials, or carbon nanowires. Electrodes 150, 155, 160, 165 may include the same materials or they may include different materials. Electrodes 150, 155, 160, 165 may provide electrical contact to the nanoparticles and allow probing and measurement of their electrical characteristics. Since the measurement device and/or related circuitry may convert an applied force, torque or acceleration to an electrical characteristic or signal, the measurement device may be considered a force transducer, a torque transducer, or an accelerometer.
Now with reference to
As illustrated, four connectors may be provided. In other embodiments, fewer connectors and related electrodes or more connectors and related electrodes may be used. For example, two connectors and electrodes may be used. In other examples, more connectors and electrodes may be used that correspond to multiple nanoparticle meshes or that correspond to a variety of locations on the nanoparticle arrays. By configuring the connectors and electrodes and by monitoring different available paths, a wide variety of characteristic data may be used to monitor the force on measurement device 100.
Sensing device 210 may output raw electrical data or sensing device 210 may output converted measurement data that may relate to a force, torque or acceleration applied on the measurement device. The converted data may be obtained by correlation using the optional processor and memory of the sensing device. For example, the processor may calculate force, torque or acceleration measurement data using conversion parameters stored in the memory or the processor may use the memory to look up the force, torque or acceleration measurement data based on the measured electrical parameters.
Referring again to
As discussed, sensing device 210 may provide raw electrical data or a raw electrical signal to device 230. Device 230 may use the raw data and may correlate it to determine a force, torque or acceleration measurement. Device 230 may use the correlated force or torque data in a variety of ways, such as, but not limited to, as a process or system monitor, as feedback to a system, or as a control parameter. Device 230 may provide output over output connection 235 to other devices, databases, or equipment.
Referring now to
In various embodiments, light source 610 may irradiate the device with light rays 620. The light rays may pass through the device and/or reflect off a part or parts of the device. In an embodiment, detector 640 may be provided to detect resultant light rays 630 that may have passed through the device. In such an embodiment, substrates 105, 120 may be at least partially transparent and they may substantially transmit light at the wavelength provided. Detector 640 may detect a parameter of the resultant light rays such as, but not limited to, a polarization change, an optical intensity change, a diffraction pattern, or the like. The optical parameter change may relate to a deformation of the device, splaying of the nanoparticles, compacting of the nanoparticles, or an interaction between the nanoparticles, as described above. Such a change may be correlated to a measurement such as a force, a torque or an acceleration. In an example, the light source and the detector may be provided at an angle with respect to a substrate surface of the device. In another example, light source 610 and detector 640 may be substantially aligned opposite the measurement device.
In another embodiment, detector 650 may be provided to detect resultant light rays 660 that may have reflected off a part of the device. In various examples, the resultant light rays may have reflected off nanoparticles 115, nanoparticles 130, couplers 110, couplers 125, or a combination thereof. In such embodiments, substrate 105 may be at least partially transparent, while substrate 120 may be transparent or opaque. As described with respect to detector 640, detector 650 may detect a parameter of the resultant light rays such as, but not limited to, a polarization change, an optical intensity change, a diffraction pattern, or the like due to a deformation of the device, and may correlate the parameter change to a measurement such as a force, a torque or an acceleration based at least in part on the optical characteristic change. Light source 610 and detector 650 may be provided in any orientation such that light rays 620 and resultant light rays 660 may reflect off the device and be captured by the detector.
In another embodiment, light source 610 may be positioned at one end of the device, and may provide light rays along an axis of the device that may be substantially along the planes of nanoparticles 115, 130. A detector may be positioned at an opposite end of the device to gather the resultant light rays and detect a parameter such as, but not limited to, a polarization change, an optical intensity change, a diffraction pattern, or the like. As discussed, the optical parameter change may correspond to a deformation of the device, and may be correlated to a measurement such as a force, a torque or an acceleration.
In various examples, a single light source may be used. In other examples, multiple light sources may be used. Similarly, one or more detectors may be used in various applications. Also, the light sources and detectors may be used in combination with the described electrodes, sensing device, other devices, and related electrical characteristics measurements or they may be used without the electrodes and related devices. In some embodiments, the illustrated electrodes may not be provided. Further, light source 610 may provide any suitable range of wavelength of light based at least in part on the materials chosen for the components of the device. The described detectors may provide raw data, raw electrical signals, or correlated measurements to another device, which may determine a correlated measurement. In some examples, the detector may include a processor and a memory that may be operable to determine correlated measurement, such as, for example, by using a look up table or calculation using known parameters. The detector may also provide output to other devices as, for example, a process or system monitor, as feedback to a system, or as a control parameter. In an example, the detector may provide an output to sensing device 210 or device 230 (please refer to
As discussed, a force may be applied at or near an end of the measurement device while the other end of the device, or the center of the device, may be secured to another substrate or mounting platform or support. The force applied and the length of the lever arm over which the force is applied may define a torque that may be acting on the device. The torque may cause a deformation of the device which may change the orientation of the nanoparticles and may cause a change in the electrical characteristics of the device that may be sensed and correlated to a torque measurement.
Referring now to
Force 740 and force 750 may be exerted on measurement device 100 in any suitable manner. For example, another object may push against or pull on the device. In other examples, measurement device 100 may be in a fluid and the fluid may exert a force as it may flow around the device or as it may change pressure in the fluid. In other examples, measurement device 100 may be bombarded by particles or particulate. In other examples, the top substrate, the bottom substrate, or both may couple by an external coupler to an object which may translate, rotate, pivot or otherwise move with respect to device 100. In an example, device 100 may be arranged to bend regardless of characteristics of the movement of the object (e.g., a linear or angular movement) based on an arrangement of coupling between device 100 and the object, thereby assessing the movement characteristics of the object by the force, torque or acceleration measured by the device. Further, although forces and torques have been discussed, measurement device 100 may also be used to measure linear or angular acceleration by measuring a temporal change in the force or torque measured. Therefore, measurement device 100 may also be considered an accelerometer.
Referring now to
Referring now to
Referring now to
From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
