Title:
Adaptive Trajectory Control for Autonomous Helicopters
Adaptive Trajectory Control for Autonomous Helicopters
Author(s)
Johnson, Eric N.
Kannan, Suresh K.
Kannan, Suresh K.
Advisor(s)
Editor(s)
Collections
Supplementary to
Permanent Link
Abstract
For autonomous helicopter flight, it is common to separate the flight control problem into an inner loop that
controls attitude and an outer loop that controls the translational trajectory of the helicopter. In previous work,
dynamic inversion and neural-network-based adaptation was used to increase performance of the attitude control
system and the method of pseudocontrol hedging (PCH) was used to protect the adaptation process from actuator
limits and dynamics. Adaptation to uncertainty in the attitude, as well as the translational dynamics, is introduced,
thus, minimizing the effects of model error in all six degrees of freedom and leading to more accurate position
tracking. The PCH method is used in a novel way that enables adaptation to occur in the outer loop without
interacting with the attitude dynamics. A pole-placement approach is used that alleviates timescale separation
requirements, allowing the outer-loop bandwidth to be closer to that of the inner loop, thus, increasing position
tracking performance. A poor model of the attitude dynamics and a basic kinematics model is shown to be sufficient
for accurate position tracking. The theory and implementation of such an approach, with a summary of flight-test
results, are described.
Sponsor
Date Issued
2005
Extent
Resource Type
Text
Resource Subtype
Article