# Robust Model Reference Adaptive Control for Tail-Sitter VTOL Aircraft

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## Abstract

**:**

## 1. Introduction

- □
- Design of Model Reference Adaptive Controller for tracking control of roll attitude for the Tail-Sitter VTOL aircraft;
- □
- Development of adaptive laws that guarantee bounded convergence of tracking and estimation error of controlled aircraft based on Lyapunov stability analysis; and
- □
- Improvement of the robustness characteristics for Model Reference Adaptive Controlled aircraft by modifying the developed adaptive laws using dead-zone modification.

## 2. Dynamic Model of Tail-Sitter VTOL UAV

## 3. Design of Adaptive Model Reference Control for Tail-Sitter VTOL Aircraft

**Theorem**

**1.**

**Proof.**

## 4. Robust Adaptive Model Reference Control

**Theorem**

**2.**

**Proof.**

## 5. Computer Simulation

#### 5.1. Scenario I: Uncertainty-Free Case

#### 5.2. Scenario II: Uncertainty Case

#### 5.3. Scenario III: Uncertainty with Modification

## 6. Conclusions

## Author Contributions

## Funding

## Conflicts of Interest

## References

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Parameter | Description | Value |
---|---|---|

${J}_{x}$ | x-axis moment of inertia | $0.0144\mathrm{kg}\xb7{\mathrm{m}}^{2}$ |

${C}_{L}$ | Roll damping coefficient | 0.36 |

$d$ | Rotor distance from the center of mass | $0.2\mathrm{m}$ |

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**MDPI and ACS Style**

Ajel, A.R.; Humaidi, A.J.; Ibraheem, I.K.; Azar, A.T.
Robust Model Reference Adaptive Control for Tail-Sitter VTOL Aircraft. *Actuators* **2021**, *10*, 162.
https://doi.org/10.3390/act10070162

**AMA Style**

Ajel AR, Humaidi AJ, Ibraheem IK, Azar AT.
Robust Model Reference Adaptive Control for Tail-Sitter VTOL Aircraft. *Actuators*. 2021; 10(7):162.
https://doi.org/10.3390/act10070162

**Chicago/Turabian Style**

Ajel, Ahmed R., Amjad J. Humaidi, Ibraheem Kasim Ibraheem, and Ahmad Taher Azar.
2021. "Robust Model Reference Adaptive Control for Tail-Sitter VTOL Aircraft" *Actuators* 10, no. 7: 162.
https://doi.org/10.3390/act10070162