Transcript Historical Overview

Historical Overview
Dry mass trends of NASA science satellites
•1950’s-1990: mass
increasing for
scientific spacecraft
•90’s: mass decreasing
SMALLSAT
REVOLUTION
Smaller Lighter Cheaper Satellites
Technology Overview
•Materials and structures have been responsible for major
improvements in aerospace systems
•For future missions the development of new structures and
materials can be a key element in reducing operating cost
and gross weight
Multifunctional
Structures
Smart Structures
MFS-Description
•structural composite
panel
•Multi-ChipModules
•Cu/Pi patches
•heat-transferring
devices embedded
•outer surface acting
as a radiator
•flexible jumpers
•electrical circuitry in
the Cu/Pi layers
•protective cover
Synergistic integration of Electronics,
Structural and Thermal control technologies
MFS-Benefits
Subsystem
C&DH
Power Distr/Drive Unit
Pyro Initiator Unit
Charge Control Unit
Cabling (Misc.)
Traditional Design
MFS Design
Mass(Kg)
Volume(in3) Mass(Kg)
Volume(in3)
10.0
681
0.6
16
9.3
850
0.6
16
4.0
189
1.2
189
18.2
400
1.0
42
•Cable-free S/C with 70% reduction in
electronic enclosures and harness
•>25% increase in payload fraction
•>50% increase in S/C volume
available for instruments or propellant
tankage
•reduced cost as MFS offers modular
architecture
•reduced “touch labor” needed in the
final S/C integration
•enhanced robustness and reliability
•wide applicability to several missions
Examples of future users:
•Next Generation Space Telescope
•Space Based Infrared System
•National Polar Orbiting Operational
Environmental Satellite
•Mars missions
MFS-State of the art
Current efforts incorporating MFS elements:
•New Millenium Program-Deep Space 1 mission
•New Millenium Program-Deep Space 2 mission
•Mighty Sat SAFI (AFRL)
•STRV 1 (DERA/BMDO/JPL)
•New Millenium Program-EO1
Technology maturity
Description
Component validation
Temp and vibe tests on SIES CR&D (AFRL)
System/Substystem or Prototype
demonstration
NMP DS1 MFS experiment
Development effort
System prototype demonstration
NMP DS1 MFS experiment
Flight qualification
Test data on DS1
Flight mission success
NMP DS1, NMP DS2, STRV
DS 1-Deep Space 1 Mission
DS1 is managed by
NASA\JPL
DS1 GOAL:
Validate technologies
required for new types of
missions
•Oct ’98: launch
•Sept ’99: primary mission
ended
•April ’99: 7 technologies
had been successfully tested
MFS experiment had been 100% validated
MFS
exp
DS 1-MFS Experiment
Experiment Goals
Demonstrate and validate MFS
technology:
– Produceability
– Flightworthiness
– Flex circuit patches and jumpers on
structure
– Socketed MCM
– Distributed temperature
measurements
– Flex circuit connections
– Hybrid cover including composite
radiation shielding material
Two validation experiments:
•Continuity check: copper polyimide layers and flex jumpers are verified as
maintaining integrity
•Thermal gradient: cycling the HiLoPDM MCM switching element which
powers a thermal simulator and analyzing the thermal gradient on the
panel
DS 1-Results
GROUND TESTING:
•Random and sine-sweep vibration
tests
•Thermal vacuum tests
FLIGHT VALIDATION:
•Performance consistent with
preflight tests
•No degradation in flex
conductor performance
•No degradation of signal in the
flight MCM socket system
•Mechanical and electrical
•No failures in the data
integrity well maintained
collection / interfacing
•MCM-component temperatures electronics
within operational temperature •100% complete (03/99)
regions
Technology effort requested
Innovative technologies are sought in the following
areas:
•Techniques for structural integration of low-volume
electronics packaging (chip-on-structure, chip-on-flex,
imbedded electronics)
•Concepts for integrating electronics, thermal management,
radiation shielding with lightweight composite structures
•Methods to rapidly assemble and disassemble or repair highly
integrated multifunctional structures or imbedded electronics
•Multifunctional structures that incorporate both power
generation and telecommunications functions
•Interchangeable structural components that can be used for
more than one function
•Integration of two or more spacecraft systems functions in
miniature components for micro-spacecraft and sensorcraft
Conclusions
•Multifunctional Structures methods are valid for flight designs
Design, integration, test, rework, flight and operation all
completed successfully
• MFS Technology is a very strong candidate for reducing mass
and volume in spacecraft design
Savings from 50% to 80% in both areas
•MFS technology supports mass production of spacecraft
Cost-effective, modular, reliable and repairable architecture
MFS IS READY FOR USE AS THE PRIMARY LOADBEARING AND ELECTRICAL CABLING METHOD FOR
CABLE-FREE SPACECRAFT
SMART-Description
A smart material provides a certain function (sensing, actuation) b
converting ENERGY from one form to another.
MECHANICAL FORCE,
DISPLACEMENT
Piezoceramics
Piezopolymers
Electrostrictors
Electrorheol. fluids
Electric
variables
(C,R,Q)
Electric
field
Piezoceramics
Piezopolymers
Electrostrictors
Electrorheol. fluids
Magnetostrictors
Magnetorheol. fluids
Magnetic
variables
(R,L)
Magnetic
field
Magnetostrictors
Magnetorheol. fluids
Thermal
energy
Shape memory alloys
Shape memory ceramics
Shape memory polymers
Light
Special gels
Chemical
energy
Ionic polymeric gels
Shape memory alloys
Shape memory ceramics
Shape memory polymers
Optical fibers
Ionic polymeric gels
SENSING
Resistance
Light
intensity
Concentration
(PH)
ACTUATION
SMART-Benefits
TRADITIONAL
TECHNOLOGIES
Stress
(Mpa)
Strain
Efficiency
Bandwidth
(Hz)
Work
(J/cm2)
Power
(J/cm3)
0.02
0.5
90%
20
0.005
0.1
Hydraulical
20
0.5
80%
4
5
20
Pneumatic
0.7
0.5
90%
20
0.175
3.5
0.35
Stress
(Mpa)
0.2
Strain
30%
Efficiency
10
Bandwidth
(Hz)
0.035
Work
(J/cm2)
0.35
Power
(J/cm3)
Shape memory
200
0.1
3%
3
10
30
Electrostrictive
50
0.002
50%
5000
0.05
250
Piezoelectric
35
0.002
50%
5000
0.035
175
Magnetostrictive
35
0.002
80%
2000
0.035
70
Contractile polymer
0.3
0.5
30%
10
0.075
0.75
Electromagnetic
Muscle
NEW
TECHNOLOGIES
• Vibration control
• Damage detection
• Increasing passengers comfort
• Improving precision pointing
•Improving aerodynamics
•Reducing manufacturing and assembly
costs
•Increasing structural life
SMART-State of the art
1880: Pierre and Jacques Curie discover piezoelectricity
1882-1917: piezoelectric research goes on as a mathematical challenge
1920-1965: first applications (vibration damping, microphones, transducers)
1965-1980: Japanese developments (signal filters, igniters, ultrasonic motors)
Late 60’s: first concept of synthesizing of smart materials and structures
•Early 90’s: work on vibration suppression applications in spacecraft, funded by the
Ballistic Missile Defense Organization (BMDO) and the US Air Force
•Since the early 90’s the Army Research Office (ARO), the Air Force (AF), the Defense
Advanced Research Project Agency (DARPA), the National Aeronautics and Space
Administration (NASA) and the Navy have ongoing programs to demonstrate the
application of smart structures in a variety of systems
At present there are three approaches to develop smart materials and structures:
1.Synthesize new materials at the atomic and molecular level
2.Develop systems with actuators and sensors attached to conventional structures
3.Develop new materials by synthesizing composite systems from known materials. These
composites contain active constituents and are used to fabricate the structure
SMART-Research
Smart materials and structures interest different fields of research:
• active noise control
• active vibration control
• precision machining and micropositioning
• aeroelastic control
• biomechanical and biomedical
(artificial muscles, valves)
• process control
(on/off shape control of solar reflectors)
• active damage control
(detection and control of delamination growth in
composite beams)
• seismic mitigation
• corrections in optical systems
• discrete and distributed actuation and control
• ultrasonic motor
Generalized acoustic
structure with local
panel actuation
SMART-Commercial applications
Smart materials have also a wide variety of commercial applications:
• piezo-damped skis and snowboards
• smart-shock for mountain bikes
• piezoelectric actuators for pneumatic valves
• electronic water-skis
• smart baseball bats
• piezoelectric flat speaker technology for computer systems
• omnicom multifunction transducer
(provides vibration, tone alert and hands-free loudspeaker functions in one
component)
SMART-Ongoing programs
•SAMPSON: Smart aircraft and marine projects demonstration
Shape control and acoustic control (DARPA, Penn State Univ, Boeing Company)
•SMART ROTOR
Control of trailing edge flaps and twist
control for helicopter rotor blades
(MIT, UCLA, ARO, Boeing, DARPA)
• SMART WING
Improve aerodynamic performance
(lift/drag and maneuver performance)
(Northrop, Lockheed Martin, Georgia Tech)
THE NUMEROUS SYSTEM DEMONSTRATIONS RECENTLY COMPLETED OR
CURRENTLY UNDERWAY INDICATE THAT SMART TECHNOLOGIES WILL LIKELY
PROVIDE NEW AND INNOVATIVE CAPABILITIES IN FUTURE COMMERCIAL AND
MILITARY AEROSPACE SYSTEMS
SMART-New technologies 1
ACTIVE FIBER COMPOSITES
Active fibers introduced into soft
polymers; electrode patterns direct field
and polarization along fibers.
ADVANTAGES: high strength, directional
actuation, conformable/large area, high
energy density
SINGLE-CRYSTAL PIEZOELECTRICS
Single-crystal piezoelectrics show high strength, large piezoelectric effects (very high
electromechanical coupling factors), field-induced strains an order of magnitude
greater than strains induced in conventional piezoceramics
TECHNICAL ISSUES
•Fabrication methods
•Integrated system design
•Reliable materials
•Fatigue life characteristics
•Lightweight materials
•Maintenance and repair procedures
SMART-New technologies 2
MEMS: Microelectromechanical systems
Electrical and mechanical functions on a single chip, realized using techniques utilized in
the manufacture of microelectronic devices (micromachining)
APPLICATIONS:
•Nozzles and nozzles arrays
•Microfluidic systems
•Sensors, actuators
•Positioners
•Pumps, valves
MAD: Meso-scale actuator
Combine MEMS technologies and smart
materials to develop a meso-scale large force
and large displacement actuator
SMART-Future 1
GOOD PROGRESS IS BEING MADE IN THE DEVELOPMENT OF ELECTRONICS,
CONTROL APPROACHES AND ANALYSIS TECHNIQUES. MORE WORK IS
NEEDED TO DEVELOP FABRICATION TECHNIQUES TO MAKE SMART
SYSTEMS AFFORDABLE. REALIZING MANY OF THE ENVISIONED
APPLICATIONS WILL DEPEND UPON THE DEVELOPMENT OF HIGHER
AUTHORITY, SOLID-STATE ACTUATORS AND INNOVATIVE CONCEPTS.
MICRO AIRCRAFT(mass of less
than 10 grams)
Project developed at MIT as a
mechanical counterpart to biological
winged flight; solid state flapping
wing propulsion and control using
piezoelectric bimorph actuators
Motivations:
•Applications in surveillance operations
•Challenging and exciting
Piezo strips
SMART-Future 2
SMART-MFS
New Shape Memory Materials
Piezo pumps
Introduzione alle strutture intelligenti
CSM
27 Luglio 2000
Prof. Paolo Gaudenzi
1. Strutture tradizionali e strutture intelligenti
2. Stato dell’arte sulla tecnologia
3. Strutture multifunzionali