Kinematic & Multibody Dynamics

At X-High Group, we leverage a diverse portfolio of commercially available and custom software solutions and in-house expertise to address mechanism simulation, routinely analyzing sophisticated nonlinear kinematic and deployable systems.

The analysis of mechanisms presents many unique challenges, including the need to accurately model multibody interaction via joints, bearings, contact, gear systems, and other constraints. Kinematic analysis is a critical element in understanding mechanism performance and loads, as are strength and structural dynamics assessments, which generally depend on mechanism configuration. Flexible multibody systems, such as deployable antennas and solar arrays, are especially challenging systems to model because they require both the articulating ability of kinematic joints and the flexible member which may include significant nonlinearity.

Robotics & Control Structure

We view the areas of robotics and controls from a multidisciplinary perspective in which kinematics, dynamics, and control systems (and potentially other fields) combine to form a problem solved through a variety of possible hardware and software solutions.

With a diverse set of education and experience backgrounds, the robotics and controls team at X-High supports both services to industrial customers and technology research and development. Our services include control system design, developing physical models, mechanical system design, and operational testing. We are actively supporting clients in industries such as entertainment, aeronautics, and materials processing.

Loads and Dynamics

X-High engineers have developed the skills and tools necessary to solve intricate and complex loads and dynamics problems, typically using advanced computational methods including finite and boundary element analysis, statistical energy analysis, computational fluid dynamics and mechanisms.

We have worked with many commercial and government customers in diverse fields, including the aerospaceand consumer-product industries. From defining the loads and environments to which your structure is exposed, to predicting the dynamic response and modifying the design to meet requirements, X-High can help.

Thermal & Aerothermal

When a system becomes too hot or cold or is continuously cycled through a large temperature range during its lifetime, mechanical problems such as structural distortion, structural failure, and equipment failure often will occur.

Because of X-High technical background in structural engineering, we also have extensive experience in thermal analysis of aerospace and electronic systems and applying the resulting thermal loads to our structural analysis models. In addition, X-High can perform multidisciplinary thermal/structural calculations.

Thermal Analysis Experience

X-High has extensive experience in aerospace systems, including defining the solar radiation environment and orbital mechanics for satellites and other orbiting systems, payload integration, prelaunch, ascent and reentry analysis, and using specialty aerospace materials including ablatives. For ground-based systems, we typically analyze electronic systems with forced or natural convection cooling. We use our analysis tools to drive the design of thermal management systems for products ranging from high-powered lasers to compact battery packs.

X-High provides thermal and coupled fluid-thermal analysis and design support at a variety of different levels of fidelity depending upon the application. This support includes the following:

  • Chip-level thermal analysis
  • Board-level thermal analysis
  • Component heat management
  • System-level thermal analysis

Our primary analysis tools are Thermal Desktop, NX Thermal, the Femap Advanced Thermal Solver, Star-CCM+, and the TMG™ and ESC™ modules of Siemens I-deas® NX Series, which have capabilities to simulate conduction, convection, radiation, and fully coupled conjugate heat transfer problems.

In addition to our expertise using commercial tools to perform thermal modeling and analysis, X-High has extensive experience developing tools, scripts, and software to go beyond standard commercial capabilities. X-High has developed commercial software to enable mapping of spatially varying data like temperature, pressure, and heat flux across models purpose-built for computational fluid dynamics (CFD), vibroacoustics, thermal, or structural analysis. X-High frequently develops user subroutines to enable modeling of complex heating such as chemical reactions or to simulate active thermal control systems. X-High also leverages application programming interface (API) language in software such as Femap and Thermal Desktop to create tools that automate modeling, analysis, and data processing activities for large models and analysis datasets. These API tools that significantly improve the productivity of our engineers are provided to our customers as a project deliverable.


Widely used in scientific, defense, and commercial applications, optical systems often have tight alignment and shape requirements that must be met despite the presence of static, dynamic, and thermal loads. These requirements often couple the optical, structural, and thermal domains and demand a coupled approach to optimize the system’s performance.

As an example, an optical instrument inside a spacecraft must meet a number of requirements:

  • Be robust enough to withstand the static and dynamic loading due to launch and ground handling
  • Function after exposure to extreme temperatures
  • Meet optical requirements in the presence of any dynamic, static, or thermal operating loads by minimizing distortions and relative displacements
  • Be designed such that its requirements for prelaunch adjustment, calibration, and testing can be met in the context of the larger system
  • Be lightweight enough to meet mass requirements

To achieve these objectives, an instrument’s design progresses through various phases that involve both analysis and test. X-High is experienced in working as a tightly integrated multidisciplinary engineering team to provide analysis and test services for ground, air, and space-based opto-mechanical systems throughout the entire design cycle to validate that the instrument design can meet its intended functionality under the operational and survival environments. This support includes initial definition of dynamic and thermal environments, analysis-driven design to optimize both structural and optical performance, and testing to correlate analytic models and qualify subsystems for their operational/qualification environments.


X-High has developed a high-fidelity, tightly integrated multiphysics analysis capability for performing aerothermoelastic simulations of aerospace structures.

X-High’s methods leverage a set of coupled software tools created to model the response of these structures. The approach improves upon traditional uncoupled methods by integrating computational fluid dynamics (CFD) codes with a computational structural dynamics (CSD) codes in a fully coupled fluid-structure interaction (FSI) form. We have integrated SIMULIA’s Co-Simulation Engine into multiple high-fidelity CFD codes to develop a multiphysics capability utilizing Abaqus for solving aerothermoelastic FSI problems. ATA has also developed our own structural dynamics solver and coupled it with multiple CFD codes.


The hypersonic environment poses extreme technology challenges for aerospace vehicles that must withstand large aerodynamic loads in exorbitant and sustained thermal environments, requiring durability with minimal weight to achieve mission speed and range goals.

Through collaborations with multiple companies and organizations, X-High Engineering has been developing a suite of tools that fill a fundamental role in the design, modeling, and analysis of hypersonic vehicles. These tools include a multiphysics engine capable of coupling high-fidelity physics solvers to capture the complex fluid, thermal, structural, and thermochemical dynamics feedback occurring between the flight vehicle and the hypersonics environment; a material characterization tool that leverages machine learning to predict the performance of a range of composite materials typically used in hypersonic applications; and a tool that accurately predicts high-speed wind tunnel transient airloads acting on test articles to promote more efficient ground test campaigns and reduce risk to facilities and program budgets.