Altair OptiStruct™

Optimization-enabled Structural Analysis

Enabling EV Excellence – Simulation Helps Rimac Improve Structural Design of Innovative Hypercar

Rimac Automobili develops and manufactures key electrification systems for global automotive companies. In addition to providing innovative electric vehicle (EV) technology that meets environmental and safety regulations, Rimac has recently introduced a second generation of its own electric hypercar – Rimac C_Two. In Rimac’s development departments, eight structural CAE engineers now work with HyperWorks. To support the structural design of the car, the team uses Altair HyperMesh and Altair HyperCrash for pre-processing. Altair Radioss is used to handle dynamic and quasistatic issues such as large structure deformations with high stresses and strains, which occur in typical crash or forming applications. Altair OptiStruct is employed for linear static and modal simulations and Altair HyperView is used for post-processing.

Customer Stories

Additive Manufacturing for Production

The Additive Manufacturing for Production survey conducted by TCT Magazine in association with Altair set out to understand the community’s desire and readiness for the much-promised land of series production using additive technologies. This collaboration between TCT and Altair was designed to understand the needs of the community in terms of current production capabilities, rate-limiting steps and areas of the technology that they believe needs improvement.

Technical Papers

Training - Save Costs by Moving Non-Linear Physics Loadcases to Altair OptiStruct

Save Costs by Moving Non-Linear Physics Loadcases to Altair OptiStruct


Training - CAD Based Parametric Optimisation Using SimLab St & HyperStudy

CAD Based Parametric Optimisation Using SimLab St & HyperStudy


Training - Nonlinear Static & Dynamic Analysis With Pretension Effects Using OptiStruct

Nonlinear Static & Dynamic Analysis With Pretension Effects Using OptiStruct


Training - MDO Director - Introduction to Altair's Multi-Disciplinary Optimization

MDO Director - Introduction to Altair's Multi-Disciplinary Optimization


Renault Nissan Mitsubishi Alliance Uses Altair SimSolid to Bring Vehicles Chassis Faster onto the Road

Renault Nissan Mitsubishi Alliance is a French-Japanese strategic partnership between the automobile manufacturers Renault (based in France), Nissan (based in Japan) and Mitsubishi Motors (based in Japan). Today, the automotive group has 122 manufacturing plants worldwide with nearly 450,000 employees controlling ten major brands: Renault, Nissan, Mitsubishi, Infiniti, Renault Samsung, Dacia, Alpine, Datsun, Venucia, and Lada. The ambition of the alliance is to offer autonomous drive, connectivity features, and services on a wide range of affordable vehicles. As part of the Renault Chassis Le Mans plant, which is building car-to-ground connecting components for the Renault Group and for the Alliance, the CTC Chassis Technical Center is a CAD engineering center where 350 engineers and technicians are working with a focus on testing and validation. Renault has been using SimSolid to perform simulations to develop lighter chassis faster.

Customer Stories

Training - Composite Design and Analysis Using HyperMesh-OptiStruct

Composite Design and Analysis Using HyperMesh-OptiStruct


OptiStruct for Linear Analysis 2019

The purpose of this self paced course is to cover basic analysis types available when using OptiStruct for Linear Analysis. The modules use the See It, Do It methodology to cover the setup, run, and post-processing of the different analysis types. See It allows you to watch a video demonstration of the exercise covered in the module. Do It provides a PDF of the exercise and a model so you to perform the exercise on your own.


Training- Aero Modelling Tools In HyperWorks

The Aero Utility tools available under User Profile>Engineering Tools>Aerospace options enables Aerospace engineers with unique modelling capabilties required in building Aero models. In this Webinar, we will explore a few of those utilities viz Airframe meshing, Composites Material Orientations, Compare FE contents and so on.


Training: Model Design Variations In Mesh Morphing Using HyperWorks New User Experience

The tool allows you to alter finite element models while keeping mesh distortions to a minimum. HyperMorph can be used to: • Change the profile and the dimensions of your mesh • Map an existing mesh onto a new geometry, and • Create shape variables that can be used for optimization


CAD & CAE Model Verification Tools Using Hyperworks New User Experience

This tool allows engineering analysts to validate CAD models received from the design teams, automatically identifying potential issues that could slow down the pre-processing stage of the simulation life cycle. The solution identifies part intersections, missing welds and incorrect bolt-nut positions on an entire assembly structure and generates comprehensive reports.

Videos, Webinars

Attaining Nonlinear and Multiphysics Mastery for SMBs with SimLab and OptiStruct

A growing number of companies aspire to perform multiphysics, but each added analysis tool introduces new complexity to a development process. Model translation, remeshing, design modification – these tasks offer no added value and increase the likelihood of error. Altair SimLab enables users to model and solve multiple physics, including nonlinear analysis, within one unified platform. Each analysis runs from one master model, allowing you to spend less time prepping and more time solving. Join the webinar to see these powerful workflows in action. In this webinar, we will demo the design of a smart speaker with an emphasis on nonlinear analysis, multiphysics, and improving perceived sound with vibro-acoustic simulation.


Generative Design Gallery

Watch the video to learn how Altair enables designs for production, moving additive manufacturing from an advanced capability to a production capacity with the power of simulation.


Accelerating Complex Linear and Nonlinear Analysis Processes from HyperMesh to OptiStruct

Supported by the streamlined, intuitive workflows in HyperMesh, running nonlinear analysis in OptiStruct is easier and more powerful than ever. Nonlinear explicit analysis is now supported, enabling simulation of drop tests, impact analysis, and more. Check out this webinar to see how Altair’s unified modeling and simulation platform can eliminate tedious meshing tasks and accelerate your nonlinear analysis processes. In this webinar, we'll demo 5 different car door abuse use-cases, solving using linear dynamics, nonlinear quasi-static implicit, and nonlinear explicit dynamics analysis in OptiStruct.


Webinar: Accurate and Efficient Simulation of Laminated Composites

Webinar: Accurate and Efficient Simulation of Laminated Composites. This webinar presents a complete composites workflow for all industries, the simulation-driven design workflow allows for an efficient process that enables time and money reduction.


Electric Motors Multidisciplinary Optimization Platform

The design of a high-performance e-Motor is a complex undertaking. Engineers have conflicting constraints to consider including efficiency, temperature, weight, size and cost. To explore more ideas, better understand their designs and improve performance, Altair HyperWorks™ has a workflow to guide motor designers through an efficient process of Simulation-Driven Design. This analysis and optimization solution supports multi-disciplinary teamwork and reduces design times.

Use Cases

Ship Foundation Design using DDAM-coupled Optimization Methods

This paper presents a case study of a ship foundation optimized for DDAM early in the design phase to validate and optimize the structural integrity of a ship foundation subject to underwater shock conditions.

Technical Papers

InnAccel Leverages Altair OptiStruct for Validating Fetal Monitoring System

A . Vijayrajan Founder and Chief Technical Officer, InnAccel talks of how simulation brings design differentiation in the medical device industry. His team speaks of the use of Altair OptiStruct non-linear solution for designing snap fit of the device carrying case.

Customer Testimonials

OptiStruct – Imperfection

Tips and Tricks #1403: OptiStruct – Imperfection Geometric imperfection can be applied to stability sensitive structures which have difficulties in being solved, because of local or global buckling.Imperfection helps to transform the bifurcation problem into a limit point problem.

Tips & Tricks

OptiStruct – PSEUDO Damage Calculation

Tips and Tricks #1404: OptiStruct – PSEUDO Damage Calculation PSEUDO damage calculation • Speedup the fatigue calculation dramatically. • Effective if the small damaged elements are not of concern. • SN/EN and Uni-axial/Multi-axial base metal fatigue with static subcase • Optimization supported.

Tips & Tricks

OptiStruct – Membranes in LGDISP & Plasticity

Tips and Tricks #1405: OptiStruct – Membranes in LGDISP & Plasticity Membranes are supported now for LGDISP NLSTAT analysis.For Nonlinear materials, plasticity is supported for membranes– both SMDISP and LGDISP.Both 1st order and 2nd order elements are supported for SMDISP and LGDISP NLSTAT.Stress on membranes should be comparable (not exact) to surface stresses on solids (which can be obtained with specifying ISOP option as INT0 in PSOLID, and output stress at GAUSS location).

Tips & Tricks

OptiStruct – New Beam Formulation

Tips and Tricks #1406: OptiStruct – New Beam Formulation New Beam Formulation (Timoshenko) • Timoshenko beam theory formulation is introduced with PARAM,BEAMALT,YES for CBAR/CBEAM.Default is NO. • With this formulation turned on, the shear deformation of the beam will be more accurate and rotary inertia will alsobe added. For the maximum accuracy, it is recommended to use PARAM,COUPMASS,YES.

Tips & Tricks

OptiStruct – CGAP Force Output Includes Preload

Tips and Tricks #1407: OptiStruct – CGAP Force Output Includes Preload CGAP Force Output Includes Preload • Preload force ‘F0’ is included in the CGAP element force output. • Preload force ‘F0’ is supported for Nonlinear static analysis (SMDISP/LGDISP), and ignored in linear analysis. • The output is available in *.h3d and/or *.op2. & with OPTI forces are written to a .force file. • With NLOUT request, incremental CGAP force output is available in *.h3d and .force file. • Currently ‘on the fly’ CGAP force output in *.impl.h3d file is not available.

Tips & Tricks

Altair OptiStruct – Viscoelastic Material

The behavior of Viscoelastic materials is intermediate between the idealized behavior of elastic solids and viscous liquids. The time domain Viscoelastic material in OptiStruct is represented by the generalized Maxwell model and is defined by a Prony series expansion.

Tips & Tricks

Altair OptiStruct – Creep Material

Creep is the permanent time dependent deformation occurring in structures, can be defined using MATVP bulk card entry. It is based on power-law model and can be used in its ‘time hardening’ form or in the corresponding ‘strain hardening’ form.

Tips & Tricks

Altair OptiStruct – Manufacturing Constraints Support for Multiple-Material Topology Optimization

All manufacturing constraints are supported for Multiple Materials Topology optimization (MMAT) from v2019.1.Different manufacturing constraints could be applied to different candidate materials in the same design domain. The original material defined by property will not be taken as candidate material by default. OptiStruct will error out if there is only one candidate material defined for the same design domain in MMAT.The element density result is available for all candidate materials in v2019.1.

Tips & Tricks

Multidisciplinary Workflow to Assess Modal Fatigue Results of a 4-Cylinder Crankshaft Using AVL EXCITE, OptiStruct and FEMFAT

The crankshaft of an engine is a highly dynamically loaded component that is continuously optimized and optimized in terms of design and production technology. In order to be able to reproduce this in the simulation, the essential influences must be considered. This includes the dynamically behaviour in combination with the engine, the material properties and the application of the loads and their transfer to other parts (bearings). The modal approach has established itself as a proven method here, whereby a modal basis is determined in the FEM so that the crankshaft is integrated as a flexible body in the MKS model of the engine, and so that an entire engine run-up can be simulated. The modal participation factors are obtained from the MBS simulation, which are used together with the modal stresses for the safety factor calculation. This workflow requires the combination of different simulation tools. The challenge is to organize the data transfer between the tools efficient and correct. In this example, the workflow is realized using OptiStruct from Altair for FEM calculation, EXCITE from AVL as MKS tool and FEMFAT from Magna Powertrain ECS as Fatigue solver. This makes it possible to simulate a complex engine run-up with consideration of the ignition bearing forces and to calculate the fatigue life of the crankshaft in FEMFAT. This webinar, details of the simulation workflow of the 4-cylinder crankshaft will be presented and the effects of several influencing variables on the fatigue life will be studied.


Development of A new vehicle front sub-frame using Altair Inspire topology optimization

Presentation by Edan Lazerson, CAE Engineer, Plasan. The Stormrider is a new vehicle which was designed from scratch and developed by Plasan. Altair Inspire was used for Topology optimization In order to find the ""best"" design for the vehicle front sub frame. The available volume (design space), 5 different load cases and target mass were specified and the optimization software calculated geometry to maximize stiffness. The optimization results were complex to manufacture with traditional technologies; the simulation and design teams collaborated on designing a manufacturable front sub frame assembly. The new design was simulated to ensure it will withstand all the required loads. The front sub frame was implemented and tested on the prototype vehicle. The optimized front sub frame proved mechanically sound, while satisfying the mass and geometrical requirements. The early stage optimization reduced the development time, by creating a valid geometry however, the topology to manufacturable design process is not trivial. In this presentation, we will present the mentioned development stages and compare the test results to the simulation predictions. Presentation at the ATCx in Israel, Netanya on October 30, 2019.

ATC Presentations

The Increased Importance of BIW & Powertrain Integration in Electric Vehicle Development

Jamie Buchanan, UK Technical Director at Altair presents at the 2019 UK e-Mobility Seminar. Global Review of the EV Architecture. Integration Opportunities (e.g. Battery System Packaging, BIW / Battery Tray Integration)

Presentations, Videos

The Challenges Associated with the Electrification of Motorsport Platforms

Michael Gascoyne, CEO of MGI Technologies presents at the UK e-Mobility seminar 2019.

Presentations, Videos

The C123 Process - A Rapid Simulation Process to Optimise the Weight & Performance Attributes of a BIW Structure

Dr. Stuart Bates, Concept Technical Specialist at Altair presents at the UK e-Mobility seminar 2019. Rapid Exploration of Packaging Alternatives e.g. Battery System Layout, Battery Frame / BIW Integration. Developing Balance Design (Weight vs Attribute Performance), Target Setting using Simulation.

Presentations, Videos

Scaling Up Your Nonlinear Analysis Solver Throughput with HyperWorks Unlimited

In this webinar, you'll learn about OptiStruct's nonlinear analysis performance at scale as well as Altair's powerful and cost-efficient solutions for on-premise or virtual compute clusters.


Nonlinear Analysis Buyer's Guide

We created this guide to help managers of CAE budgets navigate the multifaceted decisions companies must make when choosing a nonlinear analysis software vendor. Additionally, we’ve compiled some tips and best practices for successfully managing these deployments to satisfy the needs of growing engineering teams while extracting maximum return on investment.


Human Plus Machine: How Sarcos is Revolutionizing the Future of Work with Industrial Robotics

With the prospect of increasing labor shortages among a wide variety of industries, combined with the significant costs of occupational injuries and the ever-increasing pressure to increase productivity, leading robotics company, Sarcos is in a unique position to deploy industrial robotics designed to increase productivity while eliminating injuries, by augmenting rather than replacing human workers. Chris Beaufait, COO of Sarcos, discusses the current robotics landscape, why automation is not the right solution to the problems industries are facing, how Sarcos and its product lineup - including the full body, fully powered Guardian XO exoskeleton - will play a critical role in defining the workforce of tomorrow, and his vision for the robotics industry over the next five to 10 years.

ATC Presentations

An Efficient and Automated Design Strategy for Multi-physics E-Motor Development

This presentation introduces an application of a unique, highly automatic, multi-physics design strategy for E-motors, based on a current program at Mercedes-AMG GmbH. The strategy considers essential development requirements including electromagnetics and thermal requirements, NVH, stress and durability. It accommodates for DOE, multi-objective optimization and design exploration methods to be used to explore and find feasible motor designs. The presentation will show how the strategy adds efficiency to the E-motor development process and how it impacts the total costs of development.

ATC Presentations

Fast Forward Your Nonlinear Analysis with OptiStruct and HyperWorks Unlimited

Take home a modern nonlinear solver and state-of-the-art compute cluster to start revolutionizing your engineering decision-making on day one. Make agile design decisions, boost throughput, and reduce time-to-market by combining the modern nonlinear solver capabilities of OptiStruct with Altair’s HyperWorks Unlimited appliance.


Design for Additive Manufacturing with Topology Optimization

Presentation by Avishai Warszawski, Mechanical Designer at IAI, Israel Aerospace Industries at the ATCx in Israel, Netanya on October 30, 2019. The goal of this project is to design a lightweight and stiff support bracket for delicate coaxes which are attached to an electronic unit. The machining design of this bracket, although very light in weight, did not provide the required stiffness and was also very expensive to manufacture. The best approach for design was only realized after the AM team was requested to find a solution. Topology optimization with Altair tools was used to define the best shape that provides the best solution. Finally, the bracket was printed in an SLM machine from AlSi10Mg. In the near future it will be qualified by dynamic tests in accordance with the defined environmental loads.

ATC Presentations

What’s the State of Nonlinear Simulation? audience survey of nonlinear simulation practices

Technical Papers

Analysis Origins: OptiStruct

This article, featured in the October 2019 issue of NAFEMS BENCHMARK Magazine, chronicles the origins and legacy of OptiStruct, an early pioneer of simulation-driven design. Features quotes from Altair CEO Jim Scapa and other influential voices from the early days of Altair's history. Article originally published in Benchmark Magazine by NAFEMS, the International Association for the Engineering Modeling, Analysis & Simulation Community. Find out more at


Fast Forward Your Nonlinear Analysis with OptiStruct

Simulate the effects of large displacements, material nonlinearity and advanced contacts with Altair OptiStruct™. OptiStruct is the industry standard for the optimization of topology, composites, mechanisms and additive manufactured parts, but over the past three decades, it has evolved into a comprehensive linear and nonlinear analysis solution, delivering the functionality that customers of traditional nonlinear implicit codes expect coupled with the high performance they need. Watch this webinar to learn about how OptiStruct is being used to reduce software cost, simulate faster, and improve design process efficiency.


Battery & Motor Thermal Management for Electric Vehicles

The key element of an electric vehicle (EV) is the battery and batteries are known to produce heat during their charge-discharge cycle. An efficient thermal management system (TMS) is of paramount importance. The battery TMS affects the cost, life, and range of the EV. A battery TMS study or an EV TMS study involves the use of thermal and fluid physics and Altair’s AcuSolve (Computational Fluid Dynamics based Simulation Technology), was used to carry out this study. The importance of finding new methods for effectively and accurately designing TMS that control temperature and optimize the performance of Li-ion batteries. This can be used to study and optimize the Battery Thermal Management System and other Thermal Management requirements arising in an electric vehicle which involves both active and passive cooling. A similar issue of heat (unwanted) exists in Motors as well, in this, we shall cover the Multiphysics simulation of Motors which shall include both electromagnetics and CFD Thermal studies of both air and liquid coolant motors.


Traction Motors Design & Multidisciplinary Optimization

Traction Motor play key role in the electric vehicle/hybrid electric vehicle (EV/HEV) development process. The design of a High-Performance e-Motor is a complex undertaking. Engineers have conflicting constraints to consider including efficiency, temperature, weight, size, and cost. To explore more ideas, better understand their designs and improve performance, Altair HyperWorks™ has a workflow to guide motor designers through an efficient process of Simulation-Driven Design. This analysis and optimization solution supports multi-disciplinary teamwork and reduces design times.


Cost Optimization in Composite Structures

Cost optimization is a driving force in all fields of industry, with every manufacturer competing to provide a cost-effective solution to the end customer. The paper addresses how to perform an early-stage design of components with emphasis on cost optimization and without consuming too much of a construction designer's precious time. The main objective of this paper is to generate a proposal for a car seat design, based on free size optimization and cost optimization using Altair OptiStruct commercial engineering software.

Technical Papers

10 Things You Didn't Know You Could Do In Altair OptiStruct

You know Altair OptiStruct as the leader in topology optimization, but did you know that the use of OptiStruct for nonlinear structural analysis has been increasing rapidly at leading companies? Teams are benefiting from a modern solver technology with linear and nonlinear capabilities – backed by Altair’s industry leading support – while reducing costs through the unique value of HyperWorks Units.


Heavy Equipment Simulations: Multi-body, Hydraulics & DEM

Presenter: Ronald Kett, Technical Specialist, Altair

For a Stewart-Gough-Platform (Hexapod), various software tools were used to study and design highly dynamic hydraulic drives together with an overall system control. Calculation of Eigenfrequencies, control design and comparison, hydraulic system design, and overall simulation control were done in Altair Activate, the mechanics of the Stewart-Gough-Platform was taken from a CAD model into Altair Inspire Motion. The co-simulation between control + hydraulics and mechanics was performed using Activate and Altair MotionSolve. Altair HyperView and HyperGraph were used to analyze and visualize the results. With the highly integrated solutions, the results could be achieved within a very short time. The different types of models (linear/simplified/full mechanics/hydraulics) made it possible to start with fast development cycles and finally achieve reliable results.

ATC Presentations, Videos

Integrated Systems Simulation from Requirements

Ed Wettlaufer, Technical Manager Mechatronics Group, Altair [on behalf of NAVAIR]

Government solicitations for proposals, or RFPs, for aircraft and airborne systems require preliminary designs with enough fidelity to accurately predict performance, in order to prove the design's ability to meet the Governments performance requirements. Modern high-performance computing provides the leverage to execute previously expensive analyses in areas such as computational fluid dynamics. The results of these high order analyses can be used to populate parameters in 1D systems models which can be easily coupled to medium order models from other disciplines. These capabilities allow the design engineer to rapidly iterate to levels of model maturity and accuracy not achievable years ago, resulting in high levels of confidence in the designs performance predictions in unprecedented time. Moving forward, Altair engineers will employ Multiphysics and co-simulation to execute the Engineering and Manufacturing Development phase (EMD) for one subsystem of the preliminary design developed in the afore mentioned pre-acquisition phase.

ATC Presentations, Videos

Experience the Sound of Your Future EV Before it is Built

Achieving the targeted brand image in a short development cycle time with minimal or zero prototypes is a major challenge faced by EV companies. To overcome this challenge, Altair, HBK and Romax have jointly developed a simulation driven process coupled with capabilities to virtually experience the noise and vibration characteristics, giving engineers a way to obtain real time performance feedbacks as the vehicle is being developed. This joint presentation on the proposed NVH development process covers a wide range of topics, including benchmarking, target setting, full vehicle and motor gearbox simulation loadcases, troubleshooting, optimization and stochastic analysis, and playback of simulation results for subjective evaluations, with a number of new technologies representing the global best practice in sound and vibration design and development. Join us to explore ways to control the sound and vibration characteristics of the vehicle, achieve the right sound, and avoid common NVH pitfalls, while accelerating time to market utilizing and experiencing virtual NVH prototypes.

ATC Presentations