From 95112f90c2e1e2403412c651d3d7a41131631d30 Mon Sep 17 00:00:00 2001 From: Thomas Dehaeze Date: Wed, 16 Dec 2020 14:07:07 +0100 Subject: [PATCH] Add some comments --- index.html | 64 +++++++++++++++++++++++++++++++++++++++--------------- index.org | 18 ++++++++++++++- 2 files changed, 64 insertions(+), 18 deletions(-) diff --git a/index.html b/index.html index c33d07c..ac15c30 100644 --- a/index.html +++ b/index.html @@ -3,7 +3,7 @@ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> - + Encoder Renishaw Vionic - Test Bench @@ -30,14 +30,15 @@

Table of Contents

+

You can find below the document of:

@@ -46,8 +47,23 @@ You can find below the document of:
  • Linear Scale
    • -
    -

    1 Encoder Model

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    + +

    +We would like to characterize the encoder measurement system. +

    + +

    +In particular, we would like to measure: +

    + + +
    +

    1 Encoder Model

    The Encoder is characterized by its dynamics \(G_m(s)\) from the “true” displacement \(y\) to measured displacement \(y_m\). @@ -58,8 +74,12 @@ Ideally, this dynamics is constant over a wide frequency band with very small ph It is also characterized by its measurement noise \(n\) that can be described by its Power Spectral Density (PSD).

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    +The model of the encoder is shown in Figure 1. +

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    + +

    encoder-model-schematic.png

    Figure 1: Model of the Encoder

    @@ -67,23 +87,33 @@ It is also characterized by its measurement noise \(n\) that can be described by
    -
    -

    2 Test-Bench Description

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    +

    2 Test-Bench Description

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    +

    +To measure the noise \(n\) of the encoder, one can rigidly fix the head and the ruler together such that no motion should be measured. +Then, the measured signal \(y_m\) corresponds to the noise \(n\). +

    + +

    +In order to measure the linearity, we have to compare the measured displacement with a reference sensor with a known linearity. +An interferometer or capacitive sensor should work. +An actuator should also be there so impose a displacement. +

    +
    - -
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    3 Measurement procedure

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    3 Measurement procedure

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    4 Measurement Results

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    4 Measurement Results

    Author: Dehaeze Thomas

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    Created: 2020-12-16 mer. 11:52

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    Created: 2020-12-16 mer. 14:07

    diff --git a/index.org b/index.org index 92954ca..f878e6c 100644 --- a/index.org +++ b/index.org @@ -42,9 +42,18 @@ * Introduction :ignore: +#+begin_note You can find below the document of: - [[file:doc/L-9517-9678-05-A_Data_sheet_VIONiC_series_en.pdf][Vionic Encoder]] - [[file:doc/L-9517-9862-01-C_Data_sheet_RKLC_EN.pdf][Linear Scale]] +#+end_note + +We would like to characterize the encoder measurement system. + +In particular, we would like to measure: +- Bandwidth/dynamics of the sensor +- Power Spectral Density of the measurement noise +- Linearity/resolution of the sensor * Encoder Model The Encoder is characterized by its dynamics $G_m(s)$ from the "true" displacement $y$ to measured displacement $y_m$. @@ -52,6 +61,8 @@ Ideally, this dynamics is constant over a wide frequency band with very small ph It is also characterized by its measurement noise $n$ that can be described by its Power Spectral Density (PSD). +The model of the encoder is shown in Figure [[fig:encoder-model-schematic]]. + #+begin_src latex :file encoder-model-schematic.pdf \begin{tikzpicture} \node[block] (G) at (0,0){$G_m(s)$}; @@ -76,8 +87,13 @@ It is also characterized by its measurement noise $n$ that can be described by i * Test-Bench Description +To measure the noise $n$ of the encoder, one can rigidly fix the head and the ruler together such that no motion should be measured. +Then, the measured signal $y_m$ corresponds to the noise $n$. + +In order to measure the linearity, we have to compare the measured displacement with a reference sensor with a known linearity. +An interferometer or capacitive sensor should work. +An actuator should also be there so impose a displacement. * Measurement procedure - * Measurement Results