2 Mapping physical systems to digital representations

Building a digital twin begins with the fundamental questions of what aspects of your physical world you should represent digitally, and how accurately you need to represent them. These decisions shape everything that follows, from the sensors you deploy and the data you collect, to the models you build and the insights you can extract. The challenge lies in translating the rich, multi-dimensional complexity of physical systems into digital representations that are both technically feasible and provide business value. Get that translation right, and your digital twin becomes a genuine tool for optimization and prediction. Get it wrong, and you’re left with an expensive data collection that doesn’t deliver meaningful results. This chapter addresses this first step—​understanding what to digitize and how to map the physical world to a digital representation.

Before diving into the technical approaches for digital representation, you must first establish clear objectives that will guide every subsequent decision about what to digitize, how to represent it, and which details matter most for your specific use case.

2.1 Defining your objectives

2.1.1 Identify specific challenges and opportunities

2.1.2 Establish measurable performance indicators and baselines

2.1.3 Map decision-making improvements

2.1.4 Define a minimum viable digital representation

2.2 A home digital twin to optimize energy and water use

2.2.1 Mapping my home to a digital representation

2.2.2 Start with what you have

2.3 Information sources for digital representation

2.3.1 Historical records

2.3.2 Photographs

2.3.3 Videos

2.3.4 Engineering documents

2.3.5 External systems

2.4 Spatial and geometric representations

2.4.1 2D geometric models

2.4.2 3D geometric models

2.5 Spatial mapping and reference systems

2.5.1 Coordinate systems and projections

2.5.2 Coordinate transformations and conversions

2.6 Deciding what you need

2.7 Summary