A model helicopter is more difficult to control than its full scale counterpart. This is due to its greater sensitivity to control inputs and disturbances as well as higher bandwidth of dynamics. This work is focused on designing practical tracking controller for a small scale helicopter following predefined trajectories. A tracking controller based on optimal control theory is synthesized as a...

Techniques for Improved Blade Vortex Interaction Modeling,”Proceedings of the 51st Annual Forum of the American Helicopter Society (Fort Worth, TX), 1995. 31Johnson, W., Helicopter Theory, Princeton Univ. Press, Princeton, NJ, 1980, Chap. 1. 32Miller, W., “Analytical/Numerical Matching and Periodic Inversion: Two Advances in Free Wake Analysis,” Ph.D. Dissertation, Dept. of Mechanical Engineeri...

In this paper, we present the design and implementation of an autonomous flight control law for a smallscale unmanned aerial vehicle (UAV) helicopter. The approach is decentralized in nature by incorporating a newly developed nonlinear control technique, namely the composite nonlinear feedback control, together with dynamic inversion. The overall control law consists of three hierarchical layer...

This paper considers two-input, two-output nonlinear adaptive model following control of a 3-DOF (degree-of-freedom) tandem rotor model helicopter. The control performance is studied by real time implementation of the control algorithms in an actual helicopter testbed. Since the decoupling matrix of the model helicopter is singular, the system is not decouplable by static state feedback, and it...

By hybrid aircraft, we mean a UAV that can vertically take-off, land and hover like a helicopter, and meanwhile can be converted to a fixed wing airplane to achieve high forward speed and long endurance than normal helicopters. This paper presents our recent work on control of a novel small scale hybrid aircraft. The proposed aircraft should follow a specific trend of trajectory to be able to c...

Helicopter landing sites in proximity to the forest fire-risk zones are necessary for the delivery of supplies and fire emergency response teams. In this paper, we initially prepared forest fire risk map using Random Forest algorithm by overlaying the effective factors on fire occurring including vegetation types, physiographic, climatic and human factors. Then, three variants of natural candid...

In this paper, a vision-based stabilization and output tracking control method for a four-rotor helicopter has been proposed. A novel 2 camera method has been described for estimating the full 6 DOF pose of the helicopter. This two camera system is consisting of a pan-tilt ground camera and an onboard camera. The pose estimation algorithm is compared in simulation to other methods (such as four...

Neural Network Identification (NNID) for modeling the dynamics of a miniature Eagle helicopter is presented in this paper. Off-line and on-line identification is carried out for both coupled and decoupled dynamics of the helicopter from the flight test data. For both the cases, identification results and the error statistics are provided. The off-line identification performs better due to suffi...

Unmanned small autonomous helicopters can perform aggressive maneuvers that will be useful for operations in challenging conditions. This paper presents an analysis of the pilot’s execution of aggressive maneuvers from flight test data, collected on an instrumented small-scale acrobatic helicopter. A full-envelope nonlinear dynamic model of the helicopter was developed and validated for aggress...

The acoustical signal generated by a helicopter, as well as many other signals, e.g., a voiced speech signal, can be described as periodic or almost periodic. When these signals are observed in the presence of other additive wide-band signals, it becomes interesting to separate these two kinds of signals. In this paper we specifically present an iterative method for separating helicopter signal...