Effect of the Simultaneous Variation in Blade Root Chord Length and Blade Taper on Maneuvering Manned Helicopter Control Effort

Abstract

In this article, the influence of simultaneous variation in blade root chord length and blade taper on the flight control effort of maneuvering helicopter is researched. For this intention, helicopter models which are complex, control-oriented, physics-based models and capturing the main-physics and essential-dynamics are benefited. The influence of simultaneous variation in the blade root chord length and blade taper (i.e., in both chordwise and lengthwise directions dependently) on the control effort of a maneuvering manned helicopter and also on the closed-loop responses are worked. Comparisons in terms of the control effort and peak-values with and without variations in the blade root chord and blade taper changes are followed. For helicopter control variance-constrained controllers (i.e. output variance-constrained controllers) are useful. Shortly, in also maneuvering flight conditions effects and benefits of simultaneous variation in blade root chord length and blade taper on the flight control effort is tried to be proved.

Keywords

• Maneuvers
• Helicopters
• Blade Root Chord Length
• Blade Taper
• Control Effort Saving
• Flight Control System
• Closed-Loop Response.

Pale Kök Veter Uzunluğu ve Pale Daralmasının Eş Zamanlı Değişiminin Manevra Yapan İnsanlı Helikopterin Kontrol Çabası Üzerindeki Etkisi

Abstract

Bu çalışmada, pale kök veter uzunluğu ve pale daralmasının eş zamanlı değişiminin manevra yapan insanlı helikopterin kontrol çabası üzerindeki etkisi araştırılmıştır. Bu maksatla karmaşık, kontrol amaçlı, fizik temelli, temel fizik ve gerekli dinamikleri içeren helikopter modellerinden faydalanılmıştır. Pale kök veter uzunluğu ve pale daralmasının (hem veter açıklığı hem de uzunluk doğrultularında aynı şekilde) eş zamanlı değişiminin manevra yapan insanlı helikopterin kontrol çabası ve ayrıca kapalı çevrim cevaplarındaki etkileri çalışılmıştır. Kontrol çabası ve pik değerler için pale kök veter uzunluğu ve pale daralmasının gerçekleştiği ve gerçekleşmediği durumlarda kıyaslamalar yapılmıştır. Kısacası pale kök veter uzunluğu ve pale daralmasının eş zamanlı değişiminin manevralı uçuş koşullarında dahi etkileri ve faydaları ispatlanmaya çalışılmıştır.

Keywords

• Manevralar
• Helikopterler
• Pale Kök Veter Uzunluğu
• Kontrol Çabası Kazancı
• Uçuş Kontrol Sistemi
• Kapalı-Çevrim Cevabı.

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