# Research on Decoupling of Parallel Six-Axis Force/Torque Sensor Based on an Independent Component Analysis

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## Abstract

**:**

## 1. Introduction

## 2. Parallel Six-Axis Force/Torque Sensor

#### 2.1. Introduction to Parallel Six-Axis Force/Torque Sensor Structure

#### 2.2. Mathematical Model of Parallel Six-Axis Force/Torque Sensor

## 3. Online Static Loading Test

#### 3.1. Introduction to Test System and Loading Method

#### 3.2. Analysis of Loading Test Results

- Adjust the arm position to the position where the sensor is loaded, adjust the DC voltage to 24 V, and run the software to reset the initial voltage.
- Perform 20 load and unload tests in sequence at the load point and store the voltage of each load point in turn.
- Perform a calibration test on the prototype according to steps (1) and (2) and save the test data to Excel.
- Check and test the test data, calculate the matrix of the fit coefficient, and determine the static performance index.

## 4. Dynamic Decoupling Research of Parallel Six-Axis Force/Torque Sensor

#### 4.1. Dynamic Decoupling Based on Diagonal Dominant Matrices (DDM)

#### 4.2. Dynamic Decoupling Based on ICA

#### 4.3. Analysis of Results

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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Converter Type | Input Range | Conversion Accuracy | Total Number of Analog Input Channels | Channel Switching Mode | System Measurement Accuracy |
---|---|---|---|---|---|

AD7321 | $\pm 5\mathrm{V}$ | 13 digits, and the 13th digit is the sign bit | Select single channel mode, a total of 6 channels | First and last channel sequence switching | $0.1\%$ |

Output Input | Channel 1 | Channel 2 | Channel 3 | ||||||
---|---|---|---|---|---|---|---|---|---|

None (V) | DDM (V) | ICA (V) | None (V) | DDM (V) | ICA (V) | None (V) | DDM (V) | ICA (V) | |

Channel 1 | 6.6 | 3.4 | 2.0 | 0.1 | 0.3 | 0.1 | 0.4 | 0 | 0.1 |

Channel 2 | 0.5 | 0.3 | 0.1 | 6.2 | 3.7 | 2.0 | 2.6 | 1.2 | 0.1 |

Channel 3 | 0.1 | 0 | 0.1 | 0.8 | 0.7 | 0.1 | 4.6 | 3.1 | 2.0 |

Output Input | Channel 1 | Channel 2 | Channel 3 | ||||||
---|---|---|---|---|---|---|---|---|---|

None (V) | DDM (V) | ICA (V) | None (V) | DDM (V) | ICA (V) | None (V) | DDM (V) | ICA (V) | |

Channel 1 | 4.0 | 2.1 | 2.0 | 0 | 0 | 0 | 0 | 0 | |

Channel 2 | 0.2 | 0.1 | 0 | 3.9 | 2.2 | 2.0 | 2 | 0.1 | 0 |

Channel 3 | 0 | 0 | 0 | 0.6 | 0 | 0 | 3 | 2.1 | 2.0 |

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**MDPI and ACS Style**

Wang, Z.; Liu, L.; Wang, K.; He, J.; Li, Z.
Research on Decoupling of Parallel Six-Axis Force/Torque Sensor Based on an Independent Component Analysis. *Symmetry* **2021**, *13*, 172.
https://doi.org/10.3390/sym13020172

**AMA Style**

Wang Z, Liu L, Wang K, He J, Li Z.
Research on Decoupling of Parallel Six-Axis Force/Torque Sensor Based on an Independent Component Analysis. *Symmetry*. 2021; 13(2):172.
https://doi.org/10.3390/sym13020172

**Chicago/Turabian Style**

Wang, Zhijun, Lu Liu, Kai Wang, Jing He, and Zhanxian Li.
2021. "Research on Decoupling of Parallel Six-Axis Force/Torque Sensor Based on an Independent Component Analysis" *Symmetry* 13, no. 2: 172.
https://doi.org/10.3390/sym13020172