RecurDyn (FunctionBay)

RecurDyn is a multi-body dynamics (MBD) simulation software developed by FunctionBay, designed for analyzing the motion behavior of complex mechanical systems under real-world conditions. It enables engineers to simulate how components interact through joints, contacts, flexible bodies, and forces—before building physical prototypes.

At its core, RecurDyn focuses on dynamic system simulation, where rigid and flexible bodies move and interact over time. Unlike static analysis tools, it captures time-dependent motion, inertia effects, and nonlinear interactions, making it particularly useful for mechanisms with multiple moving parts.

One of RecurDyn’s defining strengths is its recursive formulation solver, which allows it to efficiently handle large-scale systems with many interconnected bodies. This makes it well-suited for industries such as automotive, robotics, heavy machinery, and defense systems, where assemblies can become computationally complex.

The platform also supports flexible body dynamics through integration with finite element methods (FEM), enabling engineers to simulate deformation alongside motion. This is critical for accurately predicting real-world behavior in components like suspension systems, tracks, belts, and compliant mechanisms.

RecurDyn includes specialized toolkits for domain-specific applications such as track systems (tracked vehicles), chains, belts, gears, and robotics, which significantly reduce setup time for common mechanical systems.

Because of these capabilities, RecurDyn is widely used in product development workflows where motion behavior, durability, and system-level interactions must be validated early in the design cycle.

Key Features

• Recursive formulation solver for efficient scaling across large serially connected body systems and high contact count problems
• MFBD integrated solver combining rigid MBD and FEA in a single solution without co-simulation overhead
• FFlex (Full Flex) nodal method providing full finite element degrees of freedom with nonlinear material and geometric deformation support
• RFlex (Reduced Flex) modal method for efficient flexible body simulation where linear deformation assumptions are sufficient
• Built-in mesh engine for flexible body creation and rigid-to-flexible conversion without external FEA preprocessing
• Advanced contact technology for gear, track, chain, and belt applications at production simulation scale
• Machinery toolkits covering Gear, Belt, Chain, Bearing, and DriveTrain applications with KISSsoft integration for gear analytic contact and transmission error analysis
• Track toolkits including TrackLM for construction equipment and TrackHM for military tracked vehicles with specialized solvers and geometry libraries
• Media transport toolkits (MTT2D and MTT3D) for flexible media transport system simulation in printing and document handling applications
• RecurDyn/CoLink for integrated mechatronic control system simulation with block diagram modeling
• RecurDyn/Control co-simulation interface to MATLAB/Simulink, AMESim, and FMI-compatible tools
• EDEM co-simulation for bulk and granular material interaction in off-road, mining, and agricultural machinery applications
• Particleworks interface for SPH-based CFD co-simulation for fluid-mechanism and fluid-flexible body coupled analysis
• AutoDesign optimization using Bayesian-motivated progressive meta-model optimization
• Durability toolkit for fatigue life and damage prediction from MFBD stress results with approximately 180 material library entries
• ProcessNet scripting in Python, C#, and VB.NET for GUI customization, task automation, and workflow development

Best For

Mechanical and systems engineers in automotive, heavy equipment, defense, industrial machinery, printing and document handling, and robotics who need to simulate large-scale multibody systems with significant contact interaction. Particularly strong for organizations working on tracked vehicle dynamics, drivetrain NVH analysis, media transport mechanism design, or any system where the recursive solver's performance advantage over global-formulation solvers produces a meaningful reduction in computation time and setup effort.

Also well positioned for teams developing Physical AI training data and sim-to-real robotics workflows that require high-fidelity mechanical simulation at scale.

Who It's Not For

Engineers whose primary requirement is vehicle dynamics with the level of institutional validation that MSC Adams carries within established automotive OEM programs. Also not the right choice for organizations whose simulation environment is deeply embedded in the Altair HyperWorks or Siemens Xcelerator ecosystems, where MotionSolve or Simpack carry stronger integration value.

RecurDyn is also not suited for simple mechanism analysis where the recursive solver's performance advantage is not relevant and a simpler or lower-cost tool would produce equivalent results.

Platform

Windows 64-bit. CAD import supporting CATIA, Parasolid, STEP, IGES, ACIS, and STL formats. Co-simulation interfaces with MATLAB/Simulink, AMESim, EDEM, Particleworks, and FMI-compatible tools. KISSsoft DriveTrain integration with Z12 file exchange. Available in standalone and floating network license configurations. Academic licensing available through FunctionBay's academic program.

Pricing

Enterprise pricing through FunctionBay and its authorized reseller network. RecurDyn/Professional is the base product required for all toolkit use, with additional toolkit licenses purchased modularly based on application requirements. Contact FunctionBay or a regional distributor for pricing by toolkit configuration and license type. Trial versions available through the FunctionBay technical support website.

Pros

• Recursive formulation delivers a genuine performance advantage for chain, track, and belt systems with large contact counts, an order-of-magnitude improvement over global-formulation solvers on appropriate problem types rather than a marginal difference
• MFBD integrated solver avoids the numerical stability and accuracy penalties associated with co-simulating rigid MBD and FEA as separate processes
• Built-in mesh engine allows flexible body creation and rigid-to-flexible body conversion without leaving the MBD environment, removing a meaningful preprocessing step from the workflow
• Domain-specific toolkits for tracks, belts, chains, gears, media transport, and engines reduce model setup time significantly compared to building equivalent systems from general contact primitives
• KISSsoft DriveTrain integration enables accurate gear transmission error prediction at the precision required for NVH analysis, backed by a validated analytical contact model
• Particleworks and EDEM co-simulation extend the platform into coupled fluid-mechanism and granular material problems that most competing MBD tools cannot address without additional software

Cons

• Enterprise pricing model requires direct reseller engagement before cost evaluation is possible
• Windows only with no Linux support, which limits HPC cluster deployment compared to tools with Linux-native solvers
• Smaller global user community and institutional reference base than MSC Adams in traditional automotive OEM environments where Adams has decades of validation history
• Toolkit-based licensing means full capability for complex multi-domain problems accumulates significant cost across multiple toolkit purchases
• Co-simulation with MATLAB/Simulink, EDEM, and Particleworks, while well supported, adds configuration and licensing complexity compared to fully integrated physics environments

Rating

⭐ 4.5 / 5

Editorial Take

RecurDyn occupies a practical middle ground between academic MBD tools and heavy enterprise simulation platforms. Its recursive solver architecture and integrated flexible body capabilities make it particularly effective for real-world mechanical systems where large contact counts, complex motion, and structural deformation must be analyzed together.

Where it stands out most clearly is in track, chain, and contact-heavy simulation problems, where competing tools often struggle with performance scaling or require significant manual setup effort. It carries a real learning investment, but for teams with serious dynamic simulation requirements in the domains it targets, it is a technically capable and computationally efficient platform.

Alternatives

MSC Adams, Altair MotionSolve, Simpack, Siemens Simcenter 3D Motion, LMS Virtual.Lab Motion, MBDyn

Used In

• Tracked vehicle dynamics for construction and military equipment
• Automotive drivetrain and transmission NVH analysis
• Chain and belt drive mechanism design
• Printer, copier, and document handling media transport systems
• Industrial robot dynamics and load analysis
• Internal combustion engine component dynamics
• Off-road vehicle and agricultural equipment bulk material interaction
• Robotics sim-to-real training data generation

Founded

1998 (FunctionBay, Inc.)