+++
title = "Position Sensors"
author = ["Thomas Dehaeze"]
draft = false
+++
Backlinks:
- [A review of nanometer resolution position sensors: operation and performance]({{< relref "fleming13_review_nanom_resol_posit_sensor" >}})
- [Measurement technologies for precision positioning]({{< relref "gao15_measur_techn_precis_posit" >}})
- [Sensors]({{< relref "sensors" >}})
- [Collocated Control]({{< relref "collocated_control" >}})
- [Inertial Sensors]({{< relref "inertial_sensors" >}})
- Tags
- [Inertial Sensors]({{< relref "inertial_sensors" >}}), [Force Sensors]({{< relref "force_sensors" >}}), [Sensor Fusion]({{< relref "sensor_fusion" >}}), [Signal Conditioner]({{< relref "signal_conditioner" >}}), [Signal to Noise Ratio]({{< relref "signal_to_noise_ratio" >}})
Reviews of Relative Position Sensors
- Fleming, A. J., A review of nanometer resolution position sensors: operation and performance (Fleming 2013) ([Notes]({{< relref "fleming13_review_nanom_resol_posit_sensor" >}}))
Technology |
Frequency |
Resolution |
Range |
T Range |
LVDT |
DC-200 Hz |
10 nm rms |
1-10 mm |
-50,100 °C |
Eddy current |
5 kHz |
0.1-100 nm rms |
0.5-55 mm |
-50,100 °C |
Capacitive |
DC-100 kHz |
0.05-50 nm rms |
50 nm - 1 cm |
-40,100 °C |
Interferometer |
300 kHz |
0.1 nm rms |
10 cm |
-250,100 °C |
Encoder |
DC-1 MHz |
1 nm rms |
7-27 mm |
0,40 °C |
Bragg Fibers |
DC-150 Hz |
0.3 nm rms |
3.5 cm |
-30,80 °C |
Sensor Type |
Range |
DNR |
Resolution |
Max. BW |
Accuracy |
Metal foil |
\(10-500 \mu m\) |
230 ppm |
23 nm |
1-10 kHz |
1% FSR |
Piezoresistive |
\(1-500 \mu m\) |
5 ppm |
0.5 nm |
>100 kHz |
1% FSR |
Capacitive |
\(10 \mu m\) to \(10 mm\) |
24 ppm |
2.4 nm |
100 kHz |
0.1% FSR |
Electrothermal |
\(10 \mu m\) to \(1 mm\) |
100 ppm |
10 nm |
10 kHz |
1% FSR |
Eddy current |
\(100 \mu m\) to \(80 mm\) |
10 ppm |
1 nm |
40 kHz |
0.1% FSR |
LVDT |
\(0.5-500 mm\) |
10 ppm |
5 nm |
1 kHz |
0.25% FSR |
Interferometer |
Meters |
|
0.5 nm |
>100kHz |
1 ppm FSR |
Encoder |
Meters |
|
6 nm |
>100kHz |
5 ppm FSR |
Capacitive Sensors and Eddy-Current sensors are compare here.
Capacitive Sensor
Description:
Manufacturers |
Links |
Country |
Micro Sense |
link |
USA |
Micro-Epsilon |
link |
Germany |
PI |
link |
Germany |
Unipulse |
link |
Japan |
Lion-Precision |
link |
USA |
Fogale |
link |
USA |
Queensgate |
link |
UK |
Capacitec |
link |
USA |
Inductive Sensor (Eddy Current)
Manufacturers |
Links |
Country |
Micro-Epsilon |
link |
Germany |
Lion Precision |
link |
USA |
Cedrat |
link |
France |
Kaman |
link |
USA |
Keyence |
link |
USA |
Inductive Sensor (LVDT)
Manufacturers |
Links |
Country |
Micro-Epsilon |
link |
Germany |
Keyence |
link |
USA |
Interferometers
Manufacturers |
Links |
Country |
Attocube |
link |
Germany |
Zygo |
link |
USA |
Smaract |
link |
Germany |
Qutools |
link |
Germany |
Renishaw |
link |
UK |
Sios |
link |
Germany |
Keysight |
link |
USA |
Optics11 |
link |
Netherlands |
Table 3:
Characteristics of Environmental Units
|
Temperature (\(\pm\ ^oC\)) |
Pressure (\(\pm\ hPa\)) |
Humidity \(\pm\% RH\) |
Wavelength Accuracy (\(\pm\ \text{ppm}\)) |
Attocube |
0.1 |
1 |
2 |
0.5 |
Renishaw |
0.2 |
1 |
6 |
1 |
Picoscale |
0.2 |
2 |
2 |
1 |
(Jang and Kim 2017)
{{< figure src="/ox-hugo/position_sensor_interferometer_precision.png" caption="Figure 1: Expected precision of interferometer as a function of measured distance" >}}
Linear Encoders
Manufacturers |
Links |
Country |
Heidenhain |
link |
Germany |
MicroE Systems |
link |
USA |
Renishaw |
link |
UK |
Celera Motion |
link |
USA |
Bibliography
Fleming, Andrew J. 2013. “A Review of Nanometer Resolution Position Sensors: Operation and Performance.” Sensors and Actuators a: Physical 190 (nil):106–26. https://doi.org/10.1016/j.sna.2012.10.016.
Jang, Yoon-Soo, and Seung-Woo Kim. 2017. “Compensation of the Refractive Index of Air in Laser Interferometer for Distance Measurement: A Review.” International Journal of Precision Engineering and Manufacturing 18 (12):1881–90. https://doi.org/10.1007/s12541-017-0217-y.