Hybrid System Based Design for the Coordination and Control of Multiple Autonomous Vehicles
Clifton, Charles Ali
:
2005-08-09
Abstract
Hybrid System Based Design for the Coordination and Control of Multiple Autonomous Vehicles
Charles A. Clifton
Thesis under the direction of Professor Takkuen John Koo
In recent years, the use of unmanned aerial vehicles (UAVs) has gained considerable attention
for applications where manned
operation is considered dangerous or infeasible. As the number of
UAVs in operation rises, it will become necessary to coordinate these vehicles. It can be shown
that a real-time system can be
modeled using a hybrid automaton provided that certain guarantees
can be made about the temporal properties. By using the hybrid automata to model the system composed
of a multi-modal dispatcher and waypoint/motion controller in addition to a real-time UAV
controller,
we show that the hybrid system can bisimulate a timed
automata model created using a tool called
UppAal, which can verify specifications about a given system. We thereby coordinate
multi-robot movement while ensuring that certain
constraints have not been violated.
In this thesis, we present a methodology for developing autonomous vehicle controllers using a
model-based approach and a hybrid automata to represent the control system, which features
both linear state feedback control and nonlinear control. We derive a linear model of the
physical system by performing system identification and employ a Kalman Filter to obtain
state estimates for feedback purposes. Furthermore, we explain how this
can be constructed
from a system containing both discrete-time linear and continuous-time nonlinear subsystems.
In addition, we
present the Vanderbilt Embedded Computing Platform for Autonomous
Vehicles (VECPAV), an end-to-end design platform for the rapid development and deployment
of control and motion planning
solutions for autonomous vehicles. The automated development
platform greatly speeds the controller and system development and
deployment phases by
reducing the programming and compilation burden on the lab researchers, and eliminating
the risks associated with translating code manually.