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ATA Engineering (ATA) provides analysis
services to support clients with their product development processes.
The staff has worked with companies over the last 30 years to help get
their products to market faster. Our experience with all analysis
issues associated with product development helps reduce the number of
prototypes and mechanical tests necessary to arrive at a high quality
product. ATA can support you with:
Aeroelastic Analysis
Airplanes, missiles, and launch vehicles must be
free of aeroelastic flutter and divergence within their operating
envelope. ATA has performed flutter and divergence analyses of many
aerospace systems, including aeroservoelastic effects. We use both
ZAERO® and NASTRAN as our aeroelastic solvers. We have worked with
ZONA Technology® to develop an interface from ZAERO® to
I-deas® to postprocess models and flutter results. We have also
developed special procedures to postprocess NASTRAN results including
V-G and V-F plots with root tracking and animated flutter mode shapes.
We have experience in subsonic, transonic, supersonic, and hypersonic
flutter analysis using ZAERO® and strip theory, doublet lattice,
Mach box, and piston theory methods in NASTRAN.
Case Studies: X-34 | Predator UAV 
High-Speed Impact Dynamics
ATA uses the Abaqus/Explicit solver to calculate
the dynamic responses of structures undergoing high speed impacts.
These solutions can handle very complex dynamic contact situations
including friction, nonlinear material behavior and failure. The
Explicit solver can also handle complicated mechanisms undergoing large
angle rotations with complex nonlinear joints. Applications include
crash analysis of automobiles, aircraft, etc., multi-body dynamics and
impact analysis of electronic components.
Mechanism Simulation
ATA performs mechanism design and analysis by
leveraging a diverse portfolio of software solutions and in-house
expertise. Project examples include implementation of I-deas in the
dynamic response analysis of robotic manipulators and the use of
MSC.ADAMS in multi-body dynamic simulation of spacecraft landing,
animatronics, and amusement park motion simulators. The ability to
incorporate flexible bodies in ADAMS and to perform design sensitivity
studies have also been utilized, as have the extensive and general
capabilities of ABAQUS to solve highly nonlinear mechanism simulation
problems involving contact and plasticity.
Noise/Vibration/Harshness (NVH)
The sound quality of today's vehicles is affected by many, often
independently designed and manufactured, automotive subsystems and
components. Consequently, developing design goals or targets that
ensure vehicle NVH acceptance and allocating these targets to bench
level component and subsystem noise and vibration targets is essential
to product development success. ATA has successfully developed
systematic procedures for identifying the sound characteristics that
determine acceptable sound quality or loudness, then breaking these
characteristics down into individual noise paths and components using
techniques such as advanced signal processing, noise path analysis,
principal component analysis, numerical trend analysis, and competitive
product assessment.
Pre-Test Analysis
A key task in many modal surveys is development of
a TAM (test-analysis model) to determine accelerometer and exciter
locations and a mass matrix for orthogonality checking of test mode
shapes. ATA has substantial capabilities for performing pretest
analysis and accurately constructing a TAM. We have found that
traditional methods (e.g., Guyan reduction) are not always appropriate.
A thorough pretest analysis can increase the productivity of the modal
survey by:
- Decreasing the number of accelerometers required and therefore the cost and schedule
- Enabling better identifications of the significant modes (by utilizing an effective mass calculation)
- Allowing for enhanced mode shape display and comparison through mode shape expansion
- Providing a foundation for test-analysis correlation of the finite element model
ATA's
software methods are very conducive to the transfer of pretest analysis
data to modal test software. This facilitates analysis-to-test
comparisons, orthogonality, etc so these tasks can be performed as soon
as test mode shapes are available (typically within a few hours of data
collection). 
Structural Analysis
ATA performs structural analysis using advanced
finite element analysis (FEA) and traditional handbook methods. We
develop, analyze, and display finite element models and results using
I-deas® Simulation pre- and post-processing and I-deas® Model
Solution Linear and Nonlinear solvers. For specialty applications, we
use additional software tools including NASTRAN, ABAQUS®, and
BOSOR®. We evaluate structural endurance using I-deas®
Durability™ and Fatigue™ modules as well as traditional
methods. We perform detailed stress analysis of fastener loads,
pullout, bearing, and other factors using established design handbooks
augmented by semi-automated procedures including Mathcad® and
spreadsheets.
Case Study: THAAD Missile Dynamic Stress Analysis 
Structural Optimization
Optimized structures provide significant benefits
including low materials cost and maximum system performance. ATA
performs structural optimization to minimize structural weight subject
to frequency, displacement, and stress constraints. We use I-deas®
optimization for statics, buckling, and modal analyses. We use NASTRAN
for specialty applications. ATA can also advise on design and
manufacturing approaches to further optimize performance and
manufacturabilty.
Thermal Model Review
Building I-deas® TMG™ thermal models is
a complex process, especially for models involving radiation and other
non-linear effects. Consequently, many models may not be designed to
maximize computational efficiency or may contain modeling inaccuracies.
As a service offered to those organizations that already use
I-deas® TMG™, ATA will review existing thermal models or
advise on how to build new models. We have extensive experience with
modeling various thermal effects, optimizing models for solution time,
and determining optimum modeling strategies. We are experts on building
models with TMG™ and the nuances of thermal analysis. Models can
be reviewed either in-house, or we can schedule an on-site visit for
you to meet with the entire thermal engineering staff.
Vibroacoustic Analysis
Extremely high sound levels can cause severe structural vibration and
fatigue problems. Typical systems with acoustic challenges include
launch vehicles, payloads, military aircraft, and commercial
transports. ATA is experienced in defining acoustic environments and
predicting structural response using the Vibro/Acoustic module in
I-deas®. We have also used VAPEPS on previous aerospace projects.
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