Mechanics – The language of the drawing

The technical drawing is one of the oldest and most important languages of engineering.

• Already in antiquity and with Leonardo da Vinci, machines were recorded in drawings.

• With industrialization the drawing was standardized (DIN, ISO) and became the universal means of communication.

• It shows geometry, dimensions, tolerances, materials – and is legally binding.

👉 No drawing, no manufacturing, no standard, no global collaboration.

Historical development

• Antiquity: construction drawings of Roman engineers (Vitruvius)

• 15th–16th centuries: Leonardo da Vinci, highly detailed machine drawings

• 18th–19th centuries: industrialization, drawing becomes the mandatory basis for manufacturing

• 20th century: standardization (DIN, ISO) makes drawings internationally valid

• Today: CAD & digital twins → but the drawing remains the legal basis

Mechanics – from clear representation to complex diversity

In mechanics there were also such “splits” or breaks between clarity and flexibility – albeit in a different way than in control engineering.

1. Early mechanics (antiquity to 18th century)

• Plans and drawings were rare and were passed down more as sketches or manuscripts.

• Much was based on craft tradition → the knowledge resided in the master’s head.

• Advantage: clarity in the craft, simple structures.

• Disadvantage: little flexibility and no uniform documentation.

---

2. Industrialization (19th century) – introduction of the technical drawing

• With industrial production the technical drawing was standardized.

• machines, components and production steps were clearly documented.

• Drawing = universal language of mechanics.

• Comparable to the relay logic in the circuit diagram: clear, traceable, securing competence.

---

3. 20th century – CAD and flexible modeling

• Introduction of CAD (Computer Aided Design) from the 1960s.

• Drawing changed from a static standard language to a dynamic 3D model.

• Advantages: enormous flexibility, fast changes, simulation.

• Disadvantage: loss of the clear paper standard – today much is “hidden” in CAD (layers, parameters, assembly logic).

• Result: clarity for the layperson lost, specialized software and expertise required.

---

4. Today – digital twins & simulation

• Models are no longer just drawings, but contain:

  • geometry

  • material data

  • manufacturing parameters

  • simulations

• Advantage: all-in-one documentation in the model.

• Disadvantage: No longer understandable at a glance – similar to PLC programming: only interpretable with special tools and know-how.

---

Conclusion: Parallel to the PLC world

• In mechanics there was likewise a development from clear, standardized language (technical drawing) toward high flexibility but lower transparency (3D-CAD, simulation).

• In electrics/logic it was similar: clearly documented logic in the circuit diagram was replaced by the flexible but opaque PLC programming .

👉 In both cases, digitization led to the general readability and unambiguity being lost. 👉 And this is precisely where the demand for a formal, understandable language for machine behavior comes in – as a new third pillar.