The University of Texas at Arlington
- Offer Profile
|Much of ARRI's research revolves around SMART MICROMACHINES which can
emulate human functions, such as, perception, cognition, motion, communication,
and interaction with the environment, humans, and among themselves.
Smart micromachines are essentially heterogeneous microscale
systems consisting of integrated sets of sensors, actuators, processors, and
fluidic, optical or RF circuits. They can be embedded into smart materials,
possibly on flexible substrates, or packaged as discrete standalone devices, or
networked into integrated systems with power harvesting, communications and/or
self-diagnostics features. Key elements of our program include a focus on
piezoelectric materials and on applications to medical microdevices.
A new generation of robots is being developed to more closely emulate human
and animal functionalities such as facial expressions, compliance, and
The goal is to develop commercializable systems for entertainment, medical
simulators, cooperative assembly with humans in a manufacturing environment,
and sensor deployment in unstructured and hostile environments.
A key element in our approach is the development of novel materials for
different types of artificial tissue. These materials are “smart” in that
they include embedded sensors, actuators and microfluidics. They can be used
to enhance the performance of humanoid and biomimetic robots and robot
- Quickskin™: embedded piezo unimophs and multifiber
composites into silicone elastomer. This sample skin is responding to
curving, folding, and punching via electrical voltages of a few volts per
Newton of applied force.
MAYA simulation interface
- A MAYA simulation interface is used to analyze the
kinematics and dynamics of the robot, and generate complex motion sequences.
- A Quickskin™ patch mounted on the CRS-A465 6-DOF Robot
arm allows an operator to move the robot arm by directly pushing on it.
- ROBOVIE-M2/M3 are biped robots with 20+ degrees of
freedom, equipped with PWM-controlled RC-servos, accelerometers, and an
on-board CPU. It is capable of throwing objects, punching, somersaulting,
doing handstands, running, side-stepping, and playing soccer!
Discrete Devices : Medical Microdevices
Research and development of miniature cost-effective microdevices including
sensors and actuators for medical applications targeting implants, in vivo
and ex vivo diagnosis and surgical instrumentations.
- Batch fabrication and manufacturing processes to ensure cost
effectiveness and miniaturization.
- Application and problem-oriented approaches to address needs in
- Target the whole systems in solving medical issue and addressing
patient’s needs and surgical/treatment procedures.
- System configurations include telemetry, micropumps, chemical
sensors, physical sensors, electrodes, optical interrogation, magnetic
interrogation, fiber optics, MEMS sensors and actuators, microrobotics
and control mechanism.
- Demonstration of in vivo near infrared fiber optics scanning probes
for brain tissue imaging, artery imaging, skin cancer early detection,
active endoscopy and retinal detachment and retinoschisis diagnosis.
- Demonstration of miniature impedance and pH sensors for GERD (gastroesophageal
reflux disease) monitoring.
- Demonstration of sensors on flexible substrates for implants.
- Micropackaging and demonstration of safe implantable drug delivery
- Demonstration of wireless chemical and physical sensors.
Applications include prevention of sudden infant death syndrome (SIDS)
and for senior/patient homecare.
- Demonstration of integrated pain management by neurostimulation.
- Design and demonstration of integrated bandages for wound healing
In vivo imaging probe.
Implantable GERD sensor on a flexible substrate.
n integrated pain management system.
Discrete Devices : Piezoactuators
Design and fabrication of high displacement and high force actuators for
applications including vibration suppression, shape-morphing, distributed
actuation, energy harvesting and health monitoring..
- Metal – ceramic composite actuators.
- Low – profile ceramic fiber composites.
- Piezoelectric motors.
- “Piezo-Bow” actuator which exhibits high displacement and high
blocking force at low frequencies was designed, analyzed and fabricated.
The structure consist of a piezoelectric bar poled along the length with
metal caps attached to the two major faces of the bar bounded by steel
- In frequency ranges below 2 kHz, a linear displacement of 8 mm at an
applied field of 3.3 V/mm was obtained. The actuator size was 7x7x30 mm³
and exhibited stresses of the order of 30 MPa.
- Experiments are in progress to design and fabricate PZT fiber based
composites which can provide high blocking force. Such actuators will
ZT fiber composite laminate.
Diagram of a PZT fiber composite laminate.
Discrete Devices : Piezotransformers
Miniaturized cell-phone battery charger using piezoelectric transformers,
and integrated note-book/laptop power adapter.
- Piezoelectric transformers with drive circuit/charger systems have
enormous potential to reduce bulky electromagnetic transformers,
increase energy efficiency and reduce the dollar cost per unit.
- Exhibit huge power densities, in the order of 40 W/cm³.
- 96%-98% efficiency range require no heat sinks.
- Provide true power isolation and eliminate stray magnetics.
- A multi-layer piezoelectric voltage and power transformer which has
one direction poling, operates in a wide-frequency range and delivers
both step-up and step-down voltages by inverting the electrical
connections has been developed, characterized and implemented.
- A complete equivalent circuit model and FEM model for the above
design has been developed and used to verify the experimental results.
iaturized piezo transformer prototype.
Discrete Devices : Energy Harvesting
Self powered sensor networks with focus on industrial health monitoring,
aircraft structural health monitoring, perimeter security nets and border
intrusion monitoring. Goal is to reach the power density of 2mW/cm².
Build several prototypes to harvest the vibration and wind energy.
Pictures below show the prototypes of the piezoelectric windmill and
vibration generator. Our current work includes the design of energy
harvesting chips, consisting of 3D layers containing multiple types of
energy capturing technologies.
The prototyping of a multi-energy input, 3D harvester is in progress.
Miniaturized windmill for powering unattended sensors.
Design and prototyping of a miniature vibration energy
Discrete Devices : Micropumps
Low-cost implantable devices for drug delivery, with flow rates in the nano
and micro liter per minute range.
- DRIE micromachined in-plane moving diaphragm structure. The in-plane
structure can create small pumping volumes for precision flow control.
Manufacturing requires only one mask to fabricate valves, pumping
chamber, actuators, and channels.
- Thermally or piezo actuated.
- Stroke amplification mechanism to increase compression ratio.
- Diffuser and nozzle structure to direct flow.
- Molded Parylene tube to insulate flow from moving diaphragm.
- Fluidic & electric interconnects using die bonding for compatibility
with fluidic boards.
- PZT out-of-plane moving diaphragm integrated with a PDMS pumping
chamber is shown below.
- Simple design with valveless structure.
- Low fabrication cost.
- Low power operation.
- High flow rate.
Implantable drug delivery systems for the treatment of diabetes, pain, or
chemotherapy. Cancer treatment will be improved by accurate, timely, and
localized drug dispensing close to tumor site maximizing the drug effect
while minimizing harmful influence on whole patient body.
- Laboratory prototypes operational and fully characterized.
- Application to in-vivo drug delivery for chemotherapy.
Design of in-plane silicon micropump.
DRIE machined silicon micropump structure.
Parylene tube placed in the pumping chamber.
Discrete Devices : Microspectrometer
Development of a miniaturized Fourier transform spectrometer (FTS) which
can be used as a hand-held, real-time, and on-site detection mechanism for
bio and chemical materials.
- Integration of heterogeneous 3-dimensional optical system on silicon
microoptical bench by combining silicon micromachining and microassembly.
- Implementation of a higher resolution spectrometer by a thermally
actuating long stroke stage.
- Precise positioning and alignment of microoptical components.
- Implementations of a miniaturized FTS by assembling micromirrors, a
ball lens, and beam splitter on SOI silicon die.
- Characterization of static and dynamic responses of the scanning
- Preliminary experiment results show that the spectrum peak was at
632nm with 25nm FWHM using He-Ne laser source and designed stroke
amplification that can produce spectral resolution of <10nm in visual
A miniaturized FTIR spectrometer.
Assembled microsphere with a silicon holder.
Discrete Devices : NOx Microsensor
Development of a capacitive, highly selective NOx sensor and integration in
a chemical health monitoring system.
- Inter-digitated electrode to detect capacitance changes.
- Deposited organic polymer films, highly selective to the target gas.
- Packaging with embedded electronics to improve sensitivity and SN
- Microfabricated electrode array and wirebonded package.
- Completed gas sensor testing infrastructure with PPB-levels gas
mixing and flow control system.
Fabricated and packaged sensor electrode.
Detection principle based on capacitance measurement.
Experimental sensor board for chemical testing.
Robotic Assembly : Multiscale & Modular Robotics
To develop a systematic methodology for designing automated machines
that enable assembly and packaging of small-scale systems. These multiscale
robots operate across scales from macro to nano, and their design is guided
by a set of hierarchical precision principles. They target low-volume pilot
production of sensors, actuators, and other heterogeneous microdevices by
using reconfigurable and modular hardware and software.
Packaged S&A Microdevice,
- manufactured at ARRI using the M³ via automated,
Robotic Assembly: Active Surfaces
Parallel manipulation of multiple micro-parts to improve throughput of
microassembly by providing gripping, sorting and aligning functions.
- Force field created by pneumatic pressure source through micron size
nozzle arrays, or through ultrasonic vibration.
- Individually controlled nozzle pressure for translation, rotation
and flipping of parts.
- Distributed manipulation algorithm to scale up for massive parallel
Active surface device using pneumatic force field.
- Prototype active surface device using pneumatic force field to
manipulate parts as small as 1mm².
- Combined piezoelectric actuation with pneumatic force field. Motion
resolution is micron range.
- Simultaneous translation, rotation, and flipping of multiple parts.
- Active surface device using pneumatic force field with
Micropackaging : Reliability
We are working on a family of reliability studies of micro-electronic and
MEMS devices. Major research is been done at ARRI on microsystem design for
reliability, hermetic packaging, and characterization of Lead-free solders.
Current Projects :
- Analysis of Lead-free solders for Electronic devices.
- Shear/tensile/vibration testing of MOEMS and microfluidic devices.
- Reliability of fluxless soldering for hermetic packaging.
- Solder ball with Cu pad with Cu-Sn intermetallic layers.
Micropackaging : Microfluidics
Modular microfluidic circuits & interconnections for multipurpose
applications in life science, chemistry, BioMEMS, and Lab-on-Chip devices.
- Low cost flexible substrates using polymer molding.
- Embedded microvalves to measure fluid volume, direct flow and
sequence discrete flow control.
- Reconfigurable circuit construction by assembly of modular
components on a platform substrate.
- Fluidic interconnection using PDMS molded adapters.
- Pneumatic pressure controlled microvalves.
- Manipulation of discrete volume fluid using fluidic gates.
- Modular microfluidic platform design, fabrication, and integration.
- An assembled flexible microfluidic circuit
- Y-shape channel for laminar flow mixer
- DMS adapter for microfluidics.
Fabrication : Femtosecond Laser Machining
- Fabrication capabilities at ARRI include access to a
Hurricane Femtosecond Ti:sapphire Laser by Spectra Physics for the
micromachining of small parts. This rapid prototyping system can produce
parts in as little as 20 to 30 minutes and is one of few available in
academia and industry in the US for machining & manufacturing.
The revolutionary advances made in the field of semiconductors, information
technology, biotechnology and medicine have led to an increased need for
better and faster microfabrication technologies. In this respect, laser
based micromachining is gaining recognition due to its numerous advantages
over traditional microfabrication processes.
Fabrication : PiezoMEMS
- Develop piezoelectric devices using MEMS technology and targeting
applications to sensors, actuators, and power generators.
- Develop piezoelectric materials and deposition processes compatible with
- ARRI MEMS software design and simulation tools include Intellisuite's
Piezo MEMS library.
Cross Section of Piezo MEMS microcantilever beam
- Sol-gel process for deposition of BaTiO3 and Pb(Zr,Ti)O3 thin films.
- Novel lithography and etching techniques to realize complex
- Combination of heterogeneous materials on the same substrate.
Process flow for depositing BT thin films.
Health Monitoring: Prognostics & Diagnostics
- Develop improved methods for intelligent automated Diagnostics and
Prognostics for engineered machinery, aerospace, and vehicle systems
- Provide a unified and rigorous framework for computer-aided
Condition-Based Maintenance (CBM) and Prognostics & Health Management (PHM)
based on wireless sensor networks
Control : Intelligent & Nonlinear Control
Develop improved control systems for modern high performance systems in
aerospace, robotics, unmanned vehicles, automotive systems, microdevices,
compute hard disk drives, and elsewhere, which are becoming more complex.
Performance requirements for these systems are becoming more rigorous in
terms of speed of response and precision of motion.
- Use biologically inspired control system structures based on neural
networks, decision-making, and linguistic fuzzy logic to avoid the need
for exact system descriptions, to avoid full internal state
measurements, and to deal with incomplete knowledge of disturbances.
- Formal derivation of digital control system structures with learning
features for implementation on computer microcontroller systems.
- Feedback Linearization that allows the control of systems with
high-frequency flexible modes such as vehicle suspension vibration, fuel
slosh, tank gun barrel vibration, aircraft flutter, computer disk drive
oscillations and windage. Neural networks allow learning of unknown
- Dynamic Inversion with a neural network learning feature for
effective compensation of actuator deadzones, uncertainties, and
- Nonlinear Lyapunov proof extension methods to determine control
system structure and neural network learning schemes that guarantee
closed-loop performance of intelligent controllers in the presence of
uncertainties and disturbances.
- High-level performance critic methods for updating control system
parameters through real-time learning techniques.
- Backstepping methods using Neural Networks to learn unknown
dynamics. This allows effective control of coupled systems with more
degrees of freedom than control inputs by using the system structure
- Adaptive Fuzzy Logic methods to allow dynamic focusing of controller
awareness on regions where more performance activity is needed.
- Actuator feedforward compensation controllers that incorporate
neural network or fuzzy logic components to offset the effects of
unknown backlash, deadzone, and friction.
- Nearly optimal control design using solution of nonlinear controller
design equations using neural network approximators.
- Development of robust output-feedback learning controllers that
operate effectively with reduced measurement information about the
- New learning control systems have been developed, simulated on
computers, and implemented on DoD, vehicle, and industry platforms.
These systems significantly improve the performance and control of
modern high-performance systems.
- Development of high performance nonlinear control system for MEMS
Control : Discrete Event Control
- Develop improved supervisory control systems for event-based systems
including manufacturing workcells, wireless sensor networks, battlefield
command and communication, and dynamic resource assignment.
- Provide a rigorous and streamlined framework for mission planning, task
sequencing, and real-time resource assignment that allows analysis of
performance, computer simulation & verification, and fast implementation of
effective supervisory controllers on actual task/resource systems.
- Discrete event controller based on matrices for efficient design,
computer simulation, and implementation.
- Matrix Graphical User Interface for ease of mission programming and
- Incorporation of the Steward Task Sequencing matrix and the Resource
Requirements matrix into a rigorous mathematical framework to calculate
the next jobs to perform and assign the required resources dynamically.
- Measurement of events, sensor readings, available resources, and
tasks accomplished in the discrete event system, and formal computation
of the next activities needed using a simplified feedback controller
- Analysis to determine the onset of blocking phenomena such as
deadlock and throughput delay, and computation of blocking avoidance
- Relation of our Matrix Feedback Controller with standard tools such
as Petri Nets and Max-Plus Algebra, which are more difficult to
implement on actual systems but have a good theoretical foundation.
- Implementation of Graphical User Interfaces in LabVIEW for easy
design for discrete event systems, including mission planning, task
sequencing, and resource pool assignment.
- A higher-level outer loop for priority task assignment, Quality of
Service, and User Selected dispatching.
- Programming of manufacturing workcells and wireless sensor networks
remotely over the internet.
- A new Matrix Framework has been developed for discrete event
supervisory control, including task assignment and dynamic resource
- The matrix framework allowed development of a new supervisory
controller that allows fast design, mission planning, computer
simulation, and actual implementation.
- A US patent has been received.
- Publication of a book on Discrete Event Control and numerous
- NSF grant received for work with Mexico universities to program
robot workcells over the internet using the new controller.
- Two Army Research Office contracts received, one for research in
discrete event control, and one DURIP to buy equipment for a Wireless
Sensor Networks Lab at ARRI.
- With our method, it is now as easy to deploy and program a wireless
sensor network as it is to program a PC.
- A wireless sensor network has been developed for Condition-Based
Maintenance of a machinery room, including equipment monitoring, fault
diagnosis, and health prognosis using advanced decision schemes.
- Implementation of our DE controller on a robotic manufacturing
workcell at ARRI.
- Implementation of our DE controller on a wireless sensor network for
environmental monitoring and area security at ARRI.
- International collaboration with leading researchers and institutes
in Europe and China
- Development of an ARRI Outreach program including local high school
Teacher Development, and summer programs for top local students
- Founded local Dallas/Fort Worth IEEE Control systems Society Chapter