Reduced-Order Active Disturbance Rejection Control for the Roll Channel of Small Fixed-Wing UAVs †

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Leblebici F., TEKİNALP O.

Engineering Proceedings, cilt.133, sa.1, 2026 (Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 133 Sayı: 1
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3390/engproc2026133085
  • Dergi Adı: Engineering Proceedings
  • Derginin Tarandığı İndeksler: Scopus, Applied Science & Technology Source, Directory of Open Access Journals
  • Anahtar Kelimeler: active disturbance rejection control, fixed-wing UAV, reduced-order extended state observer, roll autopilot
  • Açık Arşiv Koleksiyonu: AVESİS Açık Erişim Koleksiyonu
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Roll autopilots of small fixed-wing unmanned aerial vehicles (UAVs) should reject roll disturbances and compensate for parameter variations during flight. This study investigates an active disturbance rejection control (ADRC) architecture based on an extended state observer (ESO), with emphasis on a reduced-order ESO (RESO), for the roll channel of a small fixed-wing UAV. The roll axis is represented by a first-order roll-rate model augmented with actuator and rate-gyro dynamics; a proportional–derivative law is applied to the tracking error, while an extended state observer estimates a lumped total disturbance, and this estimate is fed forward for real-time disturbance compensation. Two observer designs are considered: a second-order linear ESO (LESO) and a first-order RESO using roll-rate and actuator feedback. Frequency-domain and time-domain analyses are carried out under aerodynamic uncertainty, actuator limits, sensor noise, and sinusoidal roll disturbances, and the RESO-based ADRC is compared with LESO-ADRC, a linear quadratic integral (LQI) controller, and a classical proportional–integral–derivative (PID) design. The simulations show that the RESO implementation retains the disturbance rejection and robustness of LESO-ADRC while reducing the observer order, and it offers improved disturbance rejection capability with acceptable noise sensitivity. These properties make RESO-based ADRC a promising candidate for real-time roll autopilots in small fixed-wing UAV applications.