An investigation will focus on
piezoelectric/hydraulic hybrid actuation systems intended for precise
displacement, high output force, and rapid response. Several objectives will
be examined associated with the development and understanding of such hybrid
actuation systems. The primary research objectives are as follows.
Design an actuator based on
piezoelectric control of hydraulic flow paths.
Develop a closed loop control
system for piezoelectric piloted hydraulic actuators.
mathematical models of fundamental components for system design and analysis.
Improve mathematical modeling of hybrid actuation systems.
- Design and prototyping will
be focused on the development of an amplification module to multiply the
displacement of piezoelectric actuators to a usable macro-scale displacement.
- Closed loop control will be
completed using dSPACE control hardware and Matlab/Simulink, and the
integrated “ControlDesk” software.
- Models of fundamental
components, i.e. piezoelectric actuators, torque blocks, spool valves..., will
be created using C++ and transferred to the Virtual Test Bed (VTB).
Within VTB, the model parameters will be variable and configurable to develop
virtual systems. The complete virtual systems can be tested and
optimized before producing any hardware prototypes for testing.
- Mathematical system modeling
and simulation will be completed through the use of software environments
including, but not limited to C++, Matlab/Simulink, and VTB.
Shown above is John Brader adjusting the camless
Intellectual Merit and Broader Impact of the
- A prototype will demonstrate
the rapid response, precise displacement, and output force available to such
hybrid systems. The initial target will be to develop an actuator to replace
the camshaft in an internal combustion engine. This type of “camless engine
actuator” will allow for infinitely variable valve timing within engines.
This represents a great leap in automotive technology and will allow for
greater control of engine power, fuel consumption and reduced emissions.
- Closed loop control of
piezoelectric piloted actuators is an advancement over existing systems in
such that, existing systems are based primarily on binary input solenoid
designs, not the infinite input position of the piezoelectric pilot. The
positioning of a piezoelectric pilot allows for alterations to hydraulic flow
paths and thereby volumetric flow rate.
- A set of variable models for hybrid actuators will be completed so future prototypes can be
tested within the same virtual environment. This will allow for comparisons
among potential hardware designs.
- Improvements to mathematical
modeling of actuation systems will allow for greater simulation accuracy for
complex dynamic system models.
The result of this investigation
will be both a physical and virtual actuation system that represents an improved
system, and the research will advance the accuracy of dynamic system modeling.