Alan Smith, Enventive
This week, Enventive director Alan Smith talks us through how to overcome a design challenge using an analytical, data-led engineering approach.
“We were contacted by a manufacturer of locking systems, door, bonnet and seat latches, hinges, lifting devices and shock absorbers, among others, that was experiencing a problem with a backrest seat latch mechanism. This particular component requires a great level of accuracy to work properly and retain durability.”
Owing to a high level of failure severity demanded by their client, there was a requirement for a robust simulation stage that proves the effective performance of the proposed design. Later in the project, a more detailed tolerance study had to confirm initial findings with a deeper level of detail.
Using spreadsheets to prove that a design is robust at professional level is exceedingly difficult. In short, optimised designs may work in isolation, but provide a sub-optimal real-world solution. For example, in variational studies, physical aspects such as friction forces, torques, and their respective tolerances must be considered and statistically mastered. A specific design may work when analysed using the nominal and tolerance worst case dimensions and later with a prototype. However, without a statistical variational approach combining GD&T (Geometric Dimensioning and Tolerancing) with physical impacts, manufacturing dispersions are highly likely to lead to a much higher level of planned preventative maintenance than expected.
The client’s team previously tried a 3D tolerance analysis software integrated with CAD. They decided that the software was not user friendly and required significant time that only a tolerancing specialist could afford. However, the Enventive Concept’s functional modelling approach was able to combine dimensional, geometric, and physical parameter analysis; automatically calculate variational force equilibrium and plot variational charts; and spot critical dispersions throughout the system’s motion range.
This approach provides an unprecedented level of insight that enables optimisation of any mechanical design.
The team already knew all the parameters contributing to dispersions, but until then, no one was able to establish the direct correlation between all of them. Using Enventive Concept, the R&D team now knows exactly the percentage of contribution of all parameters, regardless of their type: forces, dimensions, perpendicularity, floating pins in hole etc.
Beyond gaining new understanding, the process also makes the design stage far more robust and reliable. The trust that their customers place in the team’s ability to anticipate and reduce the risks for unexpected non-quality is crucial; an approach that fosters long-term success of any professional partnership.
Having established the cost and time benefits of utilising this approach, the client is now working on spreading the software’s usage to development of other products, such as double hinges, pedal box systems and more.