Pioneering advances in almost all fields of manufacturing, science, and technology have introduced the need to accurately measure the vibration and position displacement of small mechanical components and assemblies.
These devices usually work at high speed with relatively slight movements, and hence they often require the usage of noncontact sensors to ensure their natural movements are not affected by the sensor itself, which otherwise could happen if contacting sensors were used. Moreover, the noncontact sensor must be extremely small and should exhibit an even smaller spatial sensing capability.
Measurement of Position/Vibration Displacement
One such example application involved the measurement of the vibration and position displacement amplitude of rigid wires, measuring 0.002” to 0.005” (50 to 125mµ) in diameter.
One particular customer attempted to perform this measurement using a range of traditional noncontact sensors employing optical, magnetics, and capacitance technology. After several unsuccessful attempts, the customer contacted MTI Instruments to find a suitable solution for this problem.
Capacitance Transducer Amplifier
Figure 1. AccumeasureT 9000.
MTI Instruments has developed a new capacitance transducer amplifier called the AccumeasureT 9000 (Figure 1). The system is capable of operating with up to 100X smaller capacitance sensing area when compared to most capacitance sensors, and yet maintains the desired levels of sensing range and standoff distance.
With the help of AccumeasureT 9000, engineers at MTI Instruments were able to design a capacitance sensor which was equipped with a sensing electrode measuring only 0.050” long and 0.005” wide. This capacitance sensor, when used with the Accumeasure 9000 amplifier at full sensitivity, could offer up to 0.008” sensing range as demanded by the application.
The 0.050” length of the sensing element was aligned with the axial length of the wire target, and the 0.005” wide dimension of the sensing element was aligned with the 0.003” diameter of the wire target.
Most capacitance transducer amplifiers offer only a 0.0005” (500µm) range with a sensor of this size, which would not be sufficient to meet the customer’s requirement.
Figures 2-4 show the gap response, lateral sensitivity, and the electric field lines from the sensing electrode to the wire, respectively.
The unique capabilities of the Accumeasure 9000 amplifier help in measuring position and vibration displacement of small targets. The tool enables MTI Instruments engineers to solve different application needs of customers in a range of research, engineering and manufacturing fields.
About MTI Instruments
MTI Instruments is a worldwide leader in the design, manufacture and engineering of non-contact measurement systems and sensors.
MTI’s main products consist of computerized general gauging instruments for position, displacement, thickness and vibration applications based on laser triangulation, fiber-optic and capacitance measurement technologies.
Microtrak Pro 2D Laser Sensor, MTI’s newest product innovation, offers an economical, industrial, high precision solution to your position, displacement and profile applications.
This information has been sourced, reviewed and adapted from materials provided by MTI Instruments Inc.
For more information on this source, please visit MTI Instruments Inc.