My first job after university was as part of a manufacturing equipment design team. I was an electrical engineer using computer-aided design (CAD) software, which I learned at community college. The relationship between the electrical drawings I was creating and the physical machine was largely left to our ability to visualize both. A motor might exist as a symbol on my electrical schematic, while its physical counterpart lived somewhere on a mechanical drawing. The two representations described different aspects of the same machine, but they were not necessarily connected.

That awkward separation worked for the most part, but it created many opportunities for errors and was a nightmare to manage. A mechanical engineer could relocate a motor, sensor or junction box without the electrical design immediately reflecting the change. Cable lengths and routing were often resolved later during machine build and intall. Engineers from different disciplines had to spend considerable time comparing drawings and communicating changes simply to ensure that the separate designs would eventually fit together.

The CAD of today is beginning to change that relationship. The growing convergence of mechanical CAD (MCAD) and electrical CAD (ECAD) is bringing the physical and electrical representations of an automated machine into a much more integrated and connected engineering environment.

This is more significant than simply putting electrical components into a 3D model. In an integrated design environment, electrical components can have both a logical identity in the schematic and a physical identity within the machine. A servo motor, for example, can be represented electrically by its drive, feedback and power connections while simultaneously being positioned on a mechanical assembly with defined mounting requirements, cable connections and physical clearances.

That connection can be particularly valuable in equipment design where electrical and mechanical systems are tightly intertwined. A designer moving a sensor may need to consider its wiring path, connector orientation, mounting hardware and accessibility. Moving a component can affect not only the mechanical structure but also cable length, energy-chain routing and the location of associated electrical equipment.

This becomes even more important as automated machinery becomes more distributed. Machines may contain servo motors, vision systems, remote I/O, safety devices, Ethernet connections and intelligent sensors spread throughout a moving mechanical system. As mentioned, each device has both a physical location and an electrical relationship to the rest of the machine. Treating those relationships independently makes design changes more difficult to manage. A connected model allows engineers to consider the physical and electrical consequences together.

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The benefits extend beyond wiring. Integrated mechanical and electrical design can help engineers coordinate control panels, sensors, actuators, junction boxes, connectors, cable trays and other components with the machine structure. It can also improve the consistency of bills of material, wire termination lists, cable pull lists and manufacturing documentation by maintaining a closer relationship between the logical design and the physical machine.

There is also a significant advantage during design reviews. Instead of asking whether a sensor will fit based solely on a two-dimensional drawing, engineers can examine its actual position relative to surrounding components. They can consider whether a technician will be able to reach the connector, whether a cable can be routed without excessive bending and whether a component can be replaced without disassembling half the machine. These questions can be addressed before any equipment is built.

Perhaps the most important change, however, is philosophical. Mechanical and electrical engineers are no longer simply creating separate drawings that someone must reconcile later. They are increasingly contributing to a shared representation of the machine.

That points toward an even more connected future for factory automation. A sensor added to an automated station could carry its electrical identity, physical location and connection information throughout the engineering process. In this regard, the CAD environment becomes less of a drawing tool and more of a central engineering database for the machine.

This can also change how automation equipment is built. If the digital design contains more of the information required to manufacture, wire, assemble and document a machine, engineers can move from designing individual components toward designing an interconnected system. Mechanical and electrical changes become easier to evaluate together rather than discovering conflicts after fabrication has already begun.

For engineers who remember when electrical and mechanical designs were largely separate worlds, this represents a substantial shift. The goal is not simply to create better 3D models or more attractive drawings. It is to remove the boundaries between disciplines that have always been designing the same machine from different perspectives.

The equipment design processes of the future will require increasingly close coordination between mechanical assemblies, electrical systems and controls. As MCAD and ECAD continue to converge, CAD software may become the place where those disciplines first come together, long before the machine is ever powered on.