kdFlex is software for multibody dynamics modeling, analysis, and simulation. Its primary goals are to support high-fidelity multibody dynamics models, achieve fast computational speed,  and offer a broad family of high-performance computational algorithms for needs across multiple domains and applications.

kdFlex is designed to handle a wide variety of complex physical multibody systems. These include rigid and flexible multibody dynamics, systems with arbitrary topologies (including serial/tree and closed-chain configurations), and both smooth and non-smooth dynamics, such as from contact and collisions.

kdFlex utilizes a minimal coordinates dynamics formulation based on the Spatial Operator Algebra (SOA) methodology. This approach minimizes the need for explicit constraints, and provide optimal,  low-cost recursive computational algorithms. These algorithms often achieve O(N) computational complexity (linear scaling with the number of bodies) in contrast with cubic complexity of conventional methods.

kdFlex includes:
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Beyond solving equations of motion, kdFlex offers several advanced computational capabilities. These include:

kdFlex is a versatile foundational tool for a wide range of engineering and research applications. Key areas include flight mechanics simulations for aerospace and aerial platforms, design and closed-loop performance analysis of guidance and control systems, mobility and autonomous system development and V&V for robotics and ground vehicles, loads analysis and operation of heavy machinery, biomechanics modeling for human motion analysis, and large-scale molecular dynamics simulations for drug design.

kdFlex provides several user-friendly interaction features. It has a rich Python interface generated from its C++ core, allowing users to define and configure models, and even modify the model topology and properties during run-time using Python scripts. It also includes built-in visualization capabilities, including a basic stick figure model for debugging and support for attaching primitive shapes and CAD parts for richer graphical representations. Additionally, it features nonlinear solvers, state space model generation methods, support for quantities with units, data logging and introspection features for users.

You can start a free trial of kdFlex here and try out the example notebooks and explore the online documentation. The support forum includes a number of resources to get started quickly!