Anything you currently have in your possession was, at one point, designed by a product engineer. This includes everything from your bed to your laptop computer and everything in between. You've probably become accustomed to having these things in your life, and as such may not appreciate exactly what goes in to the design of such items. Well, below are the three pillars of product design that were in place for every good design made:
Engineering and Material Theory
For any product to be made, whether it is a new smartphone or a new car, engineers have to apply fundamental concepts in order to design the product. This theory may come from a variety of disciplines, such as: mechanical engineering, structural engineering, electrical engineering or material science. Engineers use the underlying concepts of these disciplines in order to create a product that is fully functional and will withstand typical 'wear and tear' from regular use.
It is important the designers make a product that is both safe for use and economically viable. As such, they will draw on different sources in order to achieve their goals. Typical things that designers will check include, but are not limited to:
- Material properties (strength, stiffness, stability).
- Yield stress (stress at which material will fail).
- Material response to strain (determined by the 'Young's Modulus').
- Material response to impact loading (collisions, accidental drops etc.)
- Fatigue life of the component.
Additionally, product design engineers will aim to design a product that is comfortable for the user. There is no benefit to designing a product that withstands significant loading but isn't comfortable for the user. As such, designers will integrate their knowledge of the above with their creativity in order to reach a solution that is suitable for both the manufacturer and the user.
Computer Aided Design
Fairly recent advances in technology allow designers and engineers to predict the typical response of product through computer aided design. You have likely come across this at some point (perhaps without realizing!), but designers will typically model their component in industry-standard software prior to commissioning construction. Typical approaches that designers take include:
- 3D modelling - to understand how the product will look when constructed.
- Stress analysis - to understand how the product will response to various loading scenarios.
- Dynamic analysis - to model the response of the product following collision.
- Fatigue analysis - to identify 'hot spots' on the product that require additional reinforcement.
In recent years, computer aided design has overtaken more traditional methods in modelling the response of structures. However, this does not negate the effectiveness of traditional calculations and analyses. Rather, computer aided design should be used to verify the engineer/designer's predictions in order to strengthen their conclusions.
Scale Modelling (Prototyping)
Although both of the above are great ways to predict the response of products in typical scenarios, there is nothing quite like creating a prototype. This involves constructing a scaled model that captures all of the important features of the product and then testing it under a number of different scenarios.
The benefit of scale models lies in the ability to extrapolate results to the full-scale product. Geometric scaling means that a prototype can be tested at a smaller level (say 1/20th of the real size) and the results obtained can be scaled to predict the response of the real product. This allows designers to visualize how the structure will respond under loading and gives them a great idea of where problems may arise. Typically, these models are run through extensive testing in order to reach a final conclusion. Hopefully, the results obtained will verify the designer's initial assumptions; however, if the results are different then this gives the designer a chance to analysis why this may be.
Overall, product design is a very iterative procedure. Designers and engineers at places like EIGERlab may jump between stages and revisit earlier stages in order to confirm their theories and understand how the product will behave. This allows them to create a product that is safe, reasonably priced and great to use...all of which are great for you!