SimPhant v2026.10.1

SimPhant combines CAD-based geometry, rigid-body physics, constraints, forces, springs, contacts, gears, and motion definitions in a desktop application with an interactive 3D viewport.

Included in this release

This release uncludes the URDF-files import for robotic simulations, adds possibility to define the non-linear spring dampers, upgrades the collision detection method considering max penetration depth, and improves the reopening projects method to load the model faster.

Release Highlights

1. The program supports a direct import of URDF files (Unified Robot Description Format) to simulate the robot models and robotic mechanisms.
2. Integration of the Non-linear compression and torsion spring dampers support defined by the user.
3. Refinement of the normal force model for the contact interaction. The damping force increases smoothly from 0 to a user-defined maximum value, C, as a specific penetration depth is reached.
4. Optional Baumgarte stabilization for the Gear Constraints is integrated in the code (not available in UI yet).
5. Optimisation of reopening the projects by optimization of saving the basic volume and mass properties of the objects: the files are loading faster now.
6. Bug fixed with the negative force definiton in the UI.

Program Highlights

• Interactive 3D visualization powered by PyVista and PyVistaQt
• Rigid-body creation from CAD meshes and procedural primitives
• URDF-models import for the robotic system simulations
• Mass, center-of-gravity, inertia tensor, and principal-axis calculations
• Reference frames and body positioning tools
• Joints including fixed, spherical, revolute, cylindrical, prismatic, and planar joints
• Forces, torques, actuators, and electric motors
• Compression springs, torsion springs, and bushings
• Non-linear springs dampers definition
• Collision and contact handling with friction options
• Spur, helical, internal, and bevel gear constraints
• Kinematic motion functions for supported joints
• Multiple numerical solver and integration methods
• Simulation playback, telemetry, CSV export, and video export
• Project save/load support using .mbd files

Documentation and video guides

• Documentation website: https://valeriy-sh79.github.io/simphant-docs/
• Documentation source: https://github.com/valeriy-sh79/simphant-docs
• SimPhant demo video: https://youtu.be/XvuY2sBuQKQ
• Installation and user guide video: https://youtu.be/UmAx7vWeA8s
• Installation and user guide video (RU): https://youtu.be/YOSsoQnl2pM?si=IbnJsYosDNky-SW4

Examples

The program includes a public Examples folder with ready-to-run .mbd models of classical physical and engineering mechanisms. These models are intended to help new users explore the software and understand how different systems are modeled in SimPhant.

Installation

Windows executable edition

• Ready-to-run Windows package
• No separate Python installation required
• Includes the Examples folder with bundled .mbd models

Download SimPhant-v2026.10.1-Windows.zip, extract it to a writable folder, and run SimPhant.exe

Python source edition

• Available automatically from the GitHub repository and source archives for this tag
• Includes the Examples folder with bundled .mbd models
• Suitable for users who want to inspect, modify, or extend SimPhant from source

Download the source archive for this release or clone the repository, install dependencies from requirements.txt, and run:

python main.py

Feedback

Bug reports, installation problems, and feature requests are welcome here:

https://github.com/valeriy-sh79/SimPhant/issues

SimPhant v2026.10.0

This release adds spline-driven time-history inputs for Forces, Torques, and Motions, and upgrades the collision detection pipeline with new per-contact advanced settings for narrow-phase tuning.

SimPhant combines CAD-based geometry, rigid-body physics, constraints, forces, springs, contacts, gears, and motion definitions in a desktop application with an interactive 3D viewport.

Included in this release

Windows executable edition

• Ready-to-run Windows package
• No separate Python installation required
• Includes the Examples folder with bundled .mbd models

Python source edition

• Available automatically from the GitHub repository and source archives for this tag
• Includes the Examples folder with bundled .mbd models
• Suitable for users who want to inspect, modify, or extend SimPhant from source

Program Highlights

• Interactive 3D visualization powered by PyVista and PyVistaQt
• Rigid-body creation from CAD meshes and procedural primitives
• Mass, center-of-gravity, inertia tensor, and principal-axis calculations
• Reference frames and body positioning tools
• Joints including fixed, spherical, revolute, cylindrical, prismatic, and planar joints
• Forces, torques, actuators, and electric motors
• Compression springs, torsion springs, and bushings
• Collision and contact handling with friction options
• Spur, helical, internal, and bevel gear constraints
• Kinematic motion functions for supported joints
• Multiple numerical solver and integration methods
• Simulation playback, telemetry, CSV export, and video export
• Project save/load support using .mbd files

Release Highlights

• Added spline(...) time-history inputs for Force, Torque, and Motion definitions: load a time/value data file (.csv or .dat) and drive the function directly from the imported curve instead of a math expression.
• Added a spline preview dialog for browsing, validating, and plotting the imported data file (via Akima interpolation) before applying it to a Force, Torque, or Motion (Spline inputs are not available for Actuator or E-Motor speed-limited modes).
• Upgraded the collision detection and contact-force pipeline for faster simulations: cached collision meshes, vectorized contact manifolds, and a JIT-compiled contact force kernel for the narrow phase.
• Added new per-Contact Pair advanced settings, Symmetric Contact Search and Contact Candidate Reduction, so narrow-phase behavior can be tuned individually for each contact instead of globally.
• Project files now save these two new per-contact settings; .mbd files from earlier versions load with both settings enabled by default.

Documentation and video guides

• Documentation website: https://valeriy-sh79.github.io/simphant-docs/
• Documentation source: https://github.com/valeriy-sh79/simphant-docs
• SimPhant demo video: https://youtu.be/XvuY2sBuQKQ
• Installation and user guide video: https://youtu.be/UmAx7vWeA8s
• Installation and user guide video (RU): https://youtu.be/YOSsoQnl2pM?si=IbnJsYosDNky-SW4

Examples

The program includes a public Examples folder with ready-to-run .mbd models of classical physical and engineering mechanisms. These models are intended to help new users explore the software and understand how different systems are modeled in SimPhant.

Installation

Windows

Download SimPhant-v2026.10.0-Windows.zip, extract it to a writable folder, and run SimPhant.exe.

Python

Download the source archive for this release or clone the repository, install dependencies from requirements.txt, and run:

python main.py

Feedback

Bug reports, installation problems, and feature requests are welcome here:

https://github.com/valeriy-sh79/SimPhant/issues

SimPhant v2026.09.1 — First Public Release

This is the first public release of SimPhant, a brand new free, open-source engineering-focused multibody dynamics (MBD) simulation environment for building, visualizing, and solving mechanical systems.

SimPhant combines CAD-based geometry, rigid-body physics, constraints, forces, springs, contacts, gears, and motion definitions in a desktop application with an interactive 3D viewport.

Included in this release

Windows executable edition

• Ready-to-run Windows package
• No separate Python installation required
• Includes the Examples folder with bundled .mbd models

Python source edition

• Available automatically from the GitHub repository and source archives for this tag
• Includes the Examples folder with bundled .mbd models
• Suitable for users who want to inspect, modify, or extend SimPhant from source

Program Highlights

• Interactive 3D visualization powered by PyVista and PyVistaQt
• Rigid-body creation from CAD meshes and procedural primitives
• Mass, center-of-gravity, inertia tensor, and principal-axis calculations
• Reference frames and body positioning tools
• Joints including fixed, spherical, revolute, cylindrical, prismatic, and planar joints
• Forces, torques, actuators, and electric motors
• Compression springs, torsion springs, and bushings
• Collision and contact handling with friction options
• Spur, helical, internal, and bevel gear constraints
• Kinematic motion functions for supported joints
• Multiple numerical solver and integration methods
• Simulation playback, telemetry, CSV export, and video export
• Project save/load support using .mbd files

Release Highlights

• Improved collision detection method in the solver
• Added links to YouTube video user guides in the About SimPhant window and README
• Updated bundled example models in the Examples folder

Documentation and video guides

• Documentation website: https://valeriy-sh79.github.io/simphant-docs/
• Documentation source: https://github.com/valeriy-sh79/simphant-docs
• SimPhant demo video: https://youtu.be/XvuY2sBuQKQ
• Installation and user guide video: https://youtu.be/UmAx7vWeA8s
• Installation and user guide video (RU): https://youtu.be/YOSsoQnl2pM?si=IbnJsYosDNky-SW4

Examples

The program includes a public Examples folder with ready-to-run .mbd models of classical physical and engineering mechanisms. These models are intended to help new users explore the software and understand how different systems are modeled in SimPhant.

Installation

Windows

Download SimPhant-v2026.09.1-Windows.zip, extract it to a writable folder, and run SimPhant.exe.

Python

Download the source archive for this release or clone the repository, install dependencies from requirements.txt, and run:

python main.py

Feedback

Bug reports, installation problems, and feature requests are welcome here:

https://github.com/valeriy-sh79/SimPhant/issues

SimPhant v2026.09.0 — Preliminary Release

This is preliminary release of SimPhant, a free, open-source engineering-focused multibody dynamics (MBD) simulation environment for building, visualizing, and solving mechanical systems.

SimPhant combines CAD-based geometry, rigid-body physics, constraints, forces, springs, contacts, gears, and motion definitions in a desktop application with an interactive 3D viewport.

Included in this release

Windows executable edition

• Ready-to-run Windows package
• No separate Python installation required
• Includes the Examples folder with bundled .mbd models

Python source edition

• Available automatically from the GitHub repository and source archives for this tag
• Includes the Examples folder with bundled .mbd models
• Suitable for users who want to inspect, modify, or extend SimPhant from source

Highlights

• Interactive 3D visualization powered by PyVista and PyVistaQt
• Rigid-body creation from CAD meshes and procedural primitives
• Mass, center-of-gravity, inertia tensor, and principal-axis calculations
• Reference frames and body positioning tools
• Joints including fixed, spherical, revolute, cylindrical, prismatic, and planar joints
• Forces, torques, actuators, and electric motors
• Compression springs, torsion springs, and bushings
• Collision and contact handling with friction options
• Spur, helical, internal, and bevel gear constraints
• Kinematic motion functions for supported joints
• Multiple numerical solver and integration methods
• Simulation playback, telemetry, CSV export, and video export
• Project save/load support using .mbd files

Examples

This release includes a public Examples folder with ready-to-run .mbd models of classical physical and engineering mechanisms. These models are intended to help new users explore the software and understand how different systems are modeled in SimPhant.

Suggested starting examples:

• Newtons_Cradle.mbd
• Gyroscope.mbd
• Differential.mbd
• Universal_Cardan_Joint_Aligned.mbd

Documentation

• Documentation website: https://valeriy-sh79.github.io/simphant-docs/
• Documentation source: https://github.com/valeriy-sh79/simphant-docs

Installation notes

Windows

Download SimPhant-v2026.09.0-Windows.zip, extract it to a writable folder, and run SimPhant.exe.

Python

Clone the repository or download the source archive for this release, install the dependencies from requirements.txt, and run:

python main.py