Building bricks – large and small ones, narrow and broad ones, tall and flat ones. We’ve all been familiar with them since our childhood days. And the things we were able to build with them. Houses, garages, castles, towers and cars – the bricks, always the same, were used with different approaches. In manufacturing engineering, this kind of building block concept is called modularization. The idea is to split the customers’ demand in such “bricks” that the replication rate increases, a higher number of possible varieties comes into play (adaptability) and, at the same time, the costs per “brick” and the related research and development costs decrease.
Driven by the automotive industry
The pioneer in this modularization was the automotive industry. Based on a common technical platform (chassis with motor and gearbox), several differently designed models entered the market separately. The best known example for this is Volkswagen. Across the entire corporate group of VW, Audi, Škoda and Seat several car models are built on a common platform: the one of the VW Golf (platform strategy). They all require big lot sizes, increasing the economic scale.
This strategy is one major factor for the success of the automotive industry. Other sectors who deal with customized solutions tend to neglect this approach for themselves, as their lot sizes are far smaller, sometimes even the first of its kind. But the market pressure to produce with high cost efficiency leads to a reconsideration of that concept. And the good news is that modularization works for engineer-to-order projects as well – with parts especially designed and made according to customers’ order.
How to define interfaces
Solutions which are exactly engineered to individual customer needs are far more difficult to design with a building brick concept. The reasons lie primarily in the interfaces. The most important key element of a modularized construction kit is to define the interfaces independently from customer needs. For high lot sizes this is far easier since, ex ante, the definition of these interfaces is based on a high number of customer demands. In the extreme opposite case – lot size 1 – some interfaces might not be visible or known at all. Where these interfaces need to be depends on the basic requirements. For a pump unit these interfaces most likely are completely different from those of a turbine or refrigeration unit. Therefore, the engineering know-how regarding the customers’ and the production processes is required.
Obstacles and how to overcome them
The major problem within a specific case was to recognize the main driver for complexity and to review and challenge the reasons for it. History (“This is how we’ve always done it.”) and personal alliances are often a hindrance in this analysis. Due to false considerations, the latter prevent necessary but uncomfortable questions being asked. And by the way, who likes the idea of his achievements being questioned and/or revised; especially when it is done by a “youngster” or outsider? To avoid this dilemma, a neutral person (who is not part of the immediate environment) should act as a moderator. Furthermore, the workshop should take place at the production line to visualize and identify the problematic issues on the spot. With the necessary empathy it is possible to question and analyze the degrees of freedom which foster these complexities and reduce them to the absolute minimum.
In order to ensure success, it is of utmost importance to find new ways and overcome historical ballast. Typically, products are divided by functions and then standardized. This method reaches its limit quite fast, as a few restrictions – like the space required – already create a bottleneck because interfaces are often defined too tightly.
It is easy to imagine that the motor compartment of a car conveys the impression of the limitations of this procedure. But if we go one step further – as VW did – and think in general functional blocks and get rid of process oriented interfaces, new opportunities occur. In the picture above, VW defined the interface “front axle to surface gas pedal”. This section within a car contains its most process chains. To modularize and standardize them is the basis of the platform strategy.
This experience of a non-visible interface for the customer can be transferred to all kinds of machines. The different view in combination with deliberately reduced degrees of freedom allows for the use of this modularization process for products with low lot sizes.
Modularization – even in case of lot size 1 – is possible if the modules
- can be separated physically and functionally;
- can easily be combined through harmonised interfaces (reduction of different interface variations);
- provide the possibility to create artificial interfaces if necessary.