Top Free & Open Source Digital Twin and Plant Simulation Tools

Digital twins and plant simulation are no longer toys for corporate R&D. Mid sized factories use them to test line changes, check robot reach, evaluate buffering, and predict the impact of new SKUs without touching the real floor.

The usual blockers: license costs, complex deployment, and vendors who assume you have a dedicated simulation team. The good news - there is a growing stack of free and open source tools that cover plant layout, material flow simulation, robotics validation, and physics based digital twins.

1. Gazebo (Ignition)

Best for: Robotics cells, AGVs, and layout level digital twins.

Gazebo is an open source robotics simulator used heavily by ROS and industrial robotics communities. It simulates robot kinematics, dynamics, sensors, and interactions with conveyors, fixtures, and AGVs in 3D. You can create a virtual copy of a workcell or small line and test:

• robot reach and collision risks
• cycle times under different paths and speeds
• interactions between robots, carts, and safety zones

It is not a full plant flow simulator, but it is ideal when your "plant" is a set of robotic cells and automated handling around machines.

License: Apache 2.0, open source.

2. Webots

Best for: Robot centric digital twins with good visual feedback.

Webots is another open source robotics and environment simulator. It supports multi robot scenarios, sensors, and physics, and integrates with ROS and custom controllers. For manufacturing, you can:

• validate robot programs offline
• test palletizing, pick and place, and machine tending
• simulate AMR / AGV navigation around equipment

It is a good choice when your main variable is robot behavior and you want a realistic 3D twin of cells, not full factory logistics.

License: Apache 2.0, open source.

3. OpenModelica

Best for: System level digital twins - drives, hydraulics, thermal systems.

OpenModelica is an open source implementation of the Modelica language - a standard for modeling multi domain physical systems. You can build models of:

• drives and motors
• hydraulic and pneumatic circuits
• thermal behavior of ovens, furnaces, cooling systems

For digital twin scenarios, OpenModelica lets you simulate "inside the machine" - how actuators and energy flows behave under different setpoints, loads, and disturbances. That model can later be linked to real data streams for calibration.

License: OSMC Public License, open source.

4. Scilab Xcos and Modelica Tools

Best for: Control logic and process simulation.

If you need block diagram style modeling but cannot justify Simulink, Scilab Xcos and Modelica based tools fill the gap. You can:

• prototype control loops for lines
• model production utilities - air, water, energy
• study interactions between control logic and physical processes

These tools are not "plant simulation" in the logistics sense, but they are important pieces of digital twin work when you want to capture the dynamics that sit under your PLC and drive logic.

License: Scilab - CeCILL, open source; Modelica tooling - various open licenses.

5. JaamSim and SimPy

Best for: Line throughput, buffers, and scheduling what-ifs.

JaamSim is a Java based open source discrete event simulation tool with a visual editor. SimPy is a Python library for discrete event simulation. Both are well suited to model:

• queues and buffers between machines
• parallel lines and merge points
• impact of changeover rules and shift patterns

You describe resources (machines, operators), processes, and arrival patterns, then simulate to see throughput, waiting times, and utilization. For many plants this is the most practical way to get a "digital twin" of flow without overcomplicating physics.

License: JaamSim - GPL; SimPy - MIT, open source.

6. AnyLogic PLE

Best for: Professional grade plant simulation on a free license.

AnyLogic PLE is a free edition of a commercial simulation tool. It is limited in model size but still powerful enough for:

• basic factory layouts and flows
• warehouse and AGV logic
• combined discrete event and agent based simulations

It is not open source, but the free tier is usable for small plants and concept validation. Good option if you want something closer to Tecnomatix Plant Simulation style, without paying for it.

License: Freemium, proprietary.

7. OpenCPN + Custom Layers

Best for: Quick and dirty visual layout twins.

Some teams use generic open visualization tools with custom layers to represent machines, flows, and constraints. The idea is simple:

• use a 2D CAD, GIS like, or diagram tool
• overlay machine states and KPI data from your monitoring system
• treat it as a "soft digital twin" for the shift

You do not get simulation, but you do get a live visual twin of the plant that operators can use without training. Here open tools matter more for visualization than physics.

License: Depends on the platform chosen.

8. Unity / Godot + Open Physics

Best for: Bespoke, high fidelity interactive twins.

If you have developers and want maximum freedom, game engines like Godot (open source) and Unity (free tiers) are viable digital twin platforms. You combine:

• 3D models of machines and layout
• physics engines for motion and collision
• data feeds from MQTT / OPC UA for live states

This path is heavier, but it gives you the ability to build a plant twin that runs on standard hardware and can be used for operator training, maintenance planning, or remote walkthroughs.

License: Godot - MIT, open source; Unity - proprietary with free tier.

9. Fledge (LF Edge)

Best for: Connecting real data to your digital twin.

Fledge, an open source industrial edge platform, is not a simulator itself, but it is key for wiring:

• OPC UA, Modbus, CNC, robot controllers
• condition monitoring and energy sensors
• custom Python or C plugins

into whatever twin you build - Grafana dashboards, WebGL visualizations, or robotics simulators. Fledge lets you treat your plant as a set of data sources that can feed models in real time.

License: Apache 2.0, open source.

10. Grafana based Twin

Best for: Time series driven plant twins without heavy 3D.

Use Grafana with a good layout background and panels placed where machines are. Live metrics, states, and alarms displayed in a floorplan style dashboard give you:

• a functional twin of behavior
• quick understanding of bottlenecks
• easy adoption by supervisors and operators

License: Grafana OSS - AGPL, open source.

Free & Open-Source Digital Twin Comparison Table

How to pick a stack

Start with the question you want answered:

• Will this line configuration hit target throughput?
  Use JaamSim or SimPy for a pure flow model.
• Will this robot cell layout actually work and be safe?
  Use Gazebo or Webots before cutting steel.
• How will this drive, furnace, or compressor behave under new conditions?
  Use OpenModelica or Scilab Xcos.
• I just want a live visual of my plant that operators understand.
  Use Grafana with a floorplan background and real data via Fledge.

Once the first use case is real, you can expand: add physics, connect more data, or wrap it in a nicer 3D shell. The point is not to impress visitors. The point is to test changes, make decisions faster, and stop guessing how your plant behaves when you pull a lever.

About MDCplus

Our key features are real-time machine monitoring for swift issue resolution, power consumption tracking to promote sustainability, computerized maintenance management to reduce downtime, and vibration diagnostics for predictive maintenance. MDCplus's solutions are tailored for diverse industries, including aerospace, automotive, precision machining, and heavy industry. By delivering actionable insights and fostering seamless integration, we empower manufacturers to boost Overall Equipment Effectiveness (OEE), reduce operational costs, and achieve sustainable growth along with future planning.