Active stabilization of slung loads in high speed flight using cable angle feedback

Mariano Scaramal, Jacob Enciu, Joseph Francis Horn

Research output: Contribution to journalConference article

Abstract

This paper addresses the problem of active stabilization of slung loads at high speed flight. To demonstrate the method, simulations of a utility helicopter with a dynamic inversion controller (as its automatic flight control system) and a CONEX cargo container were used. An airspeed scheduled controller utilizing cable angle feedback was designed for the nonlinear coupled system by the classic root locus technique. Nonlinear simulations of straight and level flight at different airspeeds were used to validate the controller performance in stabilizing the load pendulum motions. Controller performance was also evaluated in complex maneuvers with different levels of turbulence. The results show that the use of cable angle feedback provides or improves system stability when turbulence is not included in the simulation. When light/moderate turbulence is present sustained limit cycle oscillations are avoided by the use of the controller. For severe turbulence levels, the controller did not provide any significant improvement.

Original languageEnglish (US)
JournalAnnual Forum Proceedings - AHS International
Volume2018-May
StatePublished - Jan 1 2018
Event74th American Helicopter Society International Annual Forum and Technology Display 2018: The Future of Vertical Flight - Phoenix, United States
Duration: May 14 2018May 17 2018

Fingerprint

Slings
Cables
Stabilization
Feedback
Controllers
Turbulence
Root loci
Flight control systems
Pendulums
System stability
Helicopters
Containers

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

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abstract = "This paper addresses the problem of active stabilization of slung loads at high speed flight. To demonstrate the method, simulations of a utility helicopter with a dynamic inversion controller (as its automatic flight control system) and a CONEX cargo container were used. An airspeed scheduled controller utilizing cable angle feedback was designed for the nonlinear coupled system by the classic root locus technique. Nonlinear simulations of straight and level flight at different airspeeds were used to validate the controller performance in stabilizing the load pendulum motions. Controller performance was also evaluated in complex maneuvers with different levels of turbulence. The results show that the use of cable angle feedback provides or improves system stability when turbulence is not included in the simulation. When light/moderate turbulence is present sustained limit cycle oscillations are avoided by the use of the controller. For severe turbulence levels, the controller did not provide any significant improvement.",
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Active stabilization of slung loads in high speed flight using cable angle feedback. / Scaramal, Mariano; Enciu, Jacob; Horn, Joseph Francis.

In: Annual Forum Proceedings - AHS International, Vol. 2018-May, 01.01.2018.

Research output: Contribution to journalConference article

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