# Self-Calibratable Absolute Modular Rotary Encoder: Development and Experimental Research

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## Abstract

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## 1. Introduction

## 2. Overview

#### 2.1. Working Principle of Optical Encoders

#### 2.2. Errors in Modular Optical Rotary Encoders

#### 2.2.1. Low-Frequency Errors

#### 2.2.2. High-Frequency Errors

## 3. Materials and Methods

#### 3.1. Development of the Sefl-Calibratable Optical Modular Encoder

#### 3.1.1. Mechanical Design of the Encoder

#### 3.1.2. Electrical Design of the Encoder

^{22}(4194304) unique absolute positions per one revolution. The principle electrical scheme is presented in Figure 6.

#### 3.2. Cross-Calibration of the Produced Optical Encoder

#### 3.3. Self-Calibration of the Developed Optical Encoder

## 4. Experimental Results

## 5. Discussion and Conclusions

- Applying a self-calibration method by integrating additional optical sensors in a modular-type optical encoder is an effective approach to eliminate its mounting errors.
- In this way, a high accuracy of the encoder is ensured, while maintaining easy installation and all the advantages of the modular kit encoder.

## Author Contributions

## Funding

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 8.**Representative plots: (

**a**) deviation plot of optical sensor S1 with marked 1st harmonic and residual deviation after the elimination of the 1st harmonic; (

**b**) residual deviation with marked 2nd harmonic; (

**c**) Fourier harmonics of sensor S1; (

**d**) angle deviations of all eight optical sensors.

**Figure 9.**Conception diagram of the specific optical sensor used in different self-calibration arrangements. Where red circles indicate the optical sensors included in each arrangement, and red squares help to distinguish optical sensors that belong to different set.

**Figure 10.**Obtained plots of angle deviation and Fourier harmonics of (

**a**) ×2 optical sensors; (

**b**) ×3 optical sensors; (

**c**) ×4 optical sensors; (

**d**) ×6 optical sensors; (

**e**) multicombination of ×2 and ×3 optical sensors; (

**f**) multicombination of ×3 and ×4 optical sensors.

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**MDPI and ACS Style**

Gurauskis, D.; Marinkovic, D.; Mažeika, D.; Kilikevičius, A.
Self-Calibratable Absolute Modular Rotary Encoder: Development and Experimental Research. *Micromachines* **2024**, *15*, 1130.
https://doi.org/10.3390/mi15091130

**AMA Style**

Gurauskis D, Marinkovic D, Mažeika D, Kilikevičius A.
Self-Calibratable Absolute Modular Rotary Encoder: Development and Experimental Research. *Micromachines*. 2024; 15(9):1130.
https://doi.org/10.3390/mi15091130

**Chicago/Turabian Style**

Gurauskis, Donatas, Dragan Marinkovic, Dalius Mažeika, and Artūras Kilikevičius.
2024. "Self-Calibratable Absolute Modular Rotary Encoder: Development and Experimental Research" *Micromachines* 15, no. 9: 1130.
https://doi.org/10.3390/mi15091130