The obtained accurate data enables our customers to automate, save costs, solve problems or develop new technologies. We develop and apply advanced sensor technologies and are constantly looking for new measuring principles to make the impossible possible.
By continuously innovating and learning, we stay ahead of the competition. You are designing a new product or machine, and somewhere a force or weight must be measured. The standard product range of force sensors and load cells don't offer a suitable solution. What now? Then you probably are looking for a customized load cell that exactly fits your machine or application.
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By strategically looking at mechanical components in your application, we can change passive components into active sensors. Tailor-made Load Cell Solutions. Innovative, high-precision measurement systems and sensor solutions are our passion. Since , Althen stands for advanced, customer-specific solutions in metrology and sensors. We offer a wide range of standard products but have the ability to fully customize a sensor or measurement system to meet your specific needs.
Known for our flexibility, experience and quality in creating innovative measurement solutions, we are ready for your future measurement challenges. Read more about Althen. One of the smallest laser triangulation sensors available worldwide! This 2D Laser Scanner has been completely redesigned to an improved non-contact measuring device.
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In this case, the probe must be closer to the target for the same zero point. Because this distance differs from the original calibration, error will be introduced. Error is also created because the probe is no longer measuring a flat surface. If the distance between the probe and the target is considered the Z axis, then an additional problem of an undersized target is that the sensor becomes sensitive to X and Y location of the probe. Without changing the gap, the output will change significantly if the probe is moved in either the X or Y axis because less of the electric field is going to the center of the target and more is going around to the sides.
Figure 10 A curved target will require that the probe be closer and the sensitivity will be affected. Shape is also a consideration. Because the probes are calibrated to a flat target, measuring a target with a curved surface will cause errors Fig. Because the probe will measure the average distance to the target, the gap at zero volts will be different than when the system was calibrated. Errors will also be introduced because of the different behavior of the electric field with the curved surface. In cases where a non-flat target must be measured, the system can be factory calibrated to the final target shape.
Alternatively, when flat calibrations are used with curved surfaces, multipliers can be provided to correct the measurement value. When the target surface is not perfectly smooth, the system will average over the area covered by the spot size of the sensor. The measurement value can change as the probe is moved across the surface due to a change in the average location of the surface.
The magnitude of this error depends on the nature and symmetry of the surface irregularities. During calibration the surface of the sensor is parallel to the target surface. If the probe or target is tilted any significant amount, the shape of the spot where the field hits the target elongates and changes the interaction of the field with the target. Because of the different behavior of the electric field, measurement errors will be introduced. At high resolutions, even a few degrees can introduce error. Parallelism must be considered when designing a fixture for the measurement.
In this temperature range, errors are less than 0. More temperature related errors are due to expansion and contraction of the measurement fixture than probe or electronics drift. A more troublesome problem is that virtually all materials used in targets and fixtures exhibit a significant expansion and contraction over this temperature range.
When this happens, the temperature related changes in the measurement are not gage error. They are real changes in the gap between the target and the probe. Careful fixture design goes a long way toward minimizing this error and maximizing accuracy. The dielectric constant of air is affected by humidity. As humidity increases the dielectric constant increases. Humidity can also interact with probe construction materials. While Lion Precision probe materials are selected to minimize these errors, in applications requiring utmost precision, control of temperature and humidity is standard practice.
Its state of the art design is driven by precision motion control electronics with positional accuracies of less than 0. The calibration system is certified on a regular basis with a NIST traceable laser interferometer. The measurement equipment used during calibration digital meters and signal generators are also calibrated to NIST traceable standards.
The calibration information for each of these pieces of equipment is kept on file for verification of traceability. Technicians use the calibration system to precisely position a calibration target at known distances to the capacitive sensor.
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The measurements at these points are collected and the sensitivity and linearity are analyzed by the calibration system. The analysis of the data is used to adjust the system being calibrated to meet order specifications. Measurements are also taken of bandwidth and output noise which affect resolution. When calibration is complete, a calibration certificate is generated. This certificate is shipped with the ordered system and archived. Calibration certificates conform to section 4.
Sensitivity indicates how much the output voltage changes as a result of a change in the gap between the target and the capacitive sensor. This means that for every 0. When the output voltage is plotted against the gap size, the slope of the line is the sensitivity. Sensitivity Error - The slope of the actual measurements deviates from the ideal slope. When sensitivity deviates from the ideal value this is called sensitivity error, gain error, or scaling error. Since sensitivity is the slope of a line, sensitivity error is usually presented as a percentage of slope; comparing the ideal slope with the actual slope.
Offset Error - A constant value is added to all measurements. Offset error occurs when a constant value is added to the output voltage of the system. However, should the offset error change after the system is zeroed, error will be introduced into the measurement. Temperature change is the primary factor in offset error.
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Lion Precision systems are compensated for temperature related offset errors to keep them less than 0. Linearity Error - Measurement data is not on a straight line. Sensitivity can vary slightly between any two points of data. This variation is called linearity error. The linearity specification is the measurement of how far the output varies from a straight line.
To calculate the linearity error, calibration data is compared to the straight line that would best fit the points. This straight reference line is calculated from the calibration data using a technique called least squares fitting. The amount of error at the point on the calibration curve that is furthest away from this ideal line is the linearity error. Linearity error is usually expressed in terms of percent of full scale. If the error at the worst point was 0. Note that linearity error does not account for errors in sensitivity. It is only a measure of the straightness of the line and not the slope of the line.
A system with gross sensitivity errors can be very linear. Error Band - the worst case deviation of the measured values from the expected values in a calibration chart. In this case, the error band is Error band accounts for the combination of linearity and sensitivity errors. It is the measurement of the worst case absolute error in the calibrated range. The error band is calculated by comparing the output voltages at specific gaps to their expected value. Bandwidth is defined as the frequency at which the output falls to -3dB.
This frequency is also called the cutoff frequency. In addition to sensing high-frequency motion, fast responding outputs maximize phase margin when used in servo-control feedback systems. Some drivers provide selectable bandwidth for maximizing either resolution or response time. Resolution is defined as the smallest reliable measurement that a system can make.
The resolution of a measurement system must be better than the final accuracy the measurement requires. If you need to know a measurement within 0. The primary determining factor of resolution is electrical noise. Electrical noise appears in the output voltage causing small instantaneous errors in the output. This noise is inherent in electronic components and can only be minimized, but never eliminated. If a driver has an output noise of 0.