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WITNESS Horizon Version 25.0 is now available. Learn more about how WITNESS Horizon 25.0 can underpin your digital transformation strategy by clicking here.

Lanner’s Witness, now apart of Twinn by Royal HaskoningDHV, is consistently the most flexible, powerful, proven process simulation technology in the world. Twinn Witness enables professional modellers to rapidly develop feature-rich models and simulation apps that provide unparalleled insight through dynamic data visualisation and freedom to test choices in a risk-free virtual environment.

User-friendly, flexible and powerful, Witness gives you detailed insights into CapEx, continuous improvement and operational improvements before you invest.

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Rapid Model Development

Compare and Optimize Business Choices

Communicate the Right Way Forward

Modelling Elements in WITNESS

Powerful Model Building Elements

Get your models up and running in no time with a wide range of standard modeling elements with unique logic controls and easy configuration.

Discrete Event and Continuous Modeling

Combine continuous flows with discrete events within models to address a wide range of business problems in the most efficient and appropriate way possible. Continuous elements enable the modeling of processes that include fluids flowing through pipes or tanks and situations where high volumes of parts pass through processes at speeds which can be more easily represented as fluid flows.

Continuous and Discrete Modelling in WITNESS
2D and 3D Model Example

2D and 3D Modelling Environment

Design your model layout and develop logic efficiently in a 2D plan view before switching to stunning 3D visualisation at the touch of a button. WITNESS Quick3D™ is powered by Virtalis Visionary Render to deliver an exceptional immersive model experience and virtual reality performance.

Interfaces for Data Driven Modelling

With open connectivity to common data sources including files (Microsoft Excel, CSV, CAD, etc), databases and cloud services, users can use live organisation data or ‘big data’ streams to drive model creation, initialisation or experimentation.

Simple Coding in WITNESS

Simple, Powerful Logic Coding

No need to delve deep into complex coding to define and structure your logic. WITNESS lets you develop your logic in compartmentalised modular blocks directly within building elements. More powerful coding techniques can be leveraged through the versatile WITNESS Action Language. WITNESS also supports external code libraries written in common languages such as C++, C# &

Embedded Business Intelligence

Get to the heart of model insights and communicate answers stakeholder questions through inbuilt charts and reports that make WITNESS the ideal predictive analytics platform for business transformation. Easily export simulation data for external analysis in your favourite BI tools.

Supports multi-core experimentation of simulations

Multi-core Processing

WITNESS offers support for multi-core processing of model execution allowing users to run parallel replications and experiments and deliver accurate results, insight clarity and outcome certainty for stakeholders in a suitable timeframe.

Discover WITNESS Horizon

Watch our overview video and discover how you can use Lanner's WITNESS Horizon to build feature rich models and predictive digital twins, to enable you to test and validate your business decisions in a virtual, risk free environment.

Easily switch between 2D and 3D views, to enable unparalleled insight into your business and its processes, in a visually rich and engaging environment.

In this video, you will be introduced to the technical capabilities within WITNESS Horizon, empowering you with the data to transform your business processes for the future.

Ready to get started? Join over 4000 modellers already using WITNESS

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System Requirements

WITNESS Horizon is supported on PC systems that meet the following minimum requirements:

  • Processor: Intel® or AMD® - Processor Speed 2GHz (higher speeds recommended)
  • Supported Windows Versions: Windows 11, Windows 10, Windows 8.1*, Windows Server 2022, Windows Server 2019, Windows Server 2016, Windows Server 2012 R2*
  • Memory: 8GB of RAM (for experimentation 16GB recommended)
  • Hard Drive: 1GB of available storage space (SSD recommended)
  • Screen: 1920 x 1080 screen resolution
  • Graphics: Graphics cards compatible with the supported Microsoft Windows Versions. WITNESS Quick3D requires an NVIDIA graphics card. Recommended adapters include NVIDIA GeForce© with at least 4GB of RAM or NVIDIA® Quadro® series. Graphics cards from other providers may be compatible but are not supported by Lanner.
  • USB:WITNESS can be issued on a USB memory stick or downloaded from the MyLanner Support Portal. A USB socket is required for a hardware 'dongle' based security solution. Other security options are available.

* For Windows 8.1 and Windows Server 2012 R2 the following additional prerequisites need to be installed - April 2014 Update (see KB2919355) and Servicing Stack Update (see KB2919442).

64 bit operating systems are supported

Note that WITNESS Horizon will not run on Windows XP.

Release Notes: Version 25.0 | Version 24.0 | Version 23.1 | Version 23 | Version 22.5 | Version 22.1 | Version 22.0