Background

The wheel-related components of the chassis - i.e. tires,  wheel hubs and bearings - are highly stressed, safety-relevant components that are directly involved in the load path without suspension and must therefore not fail to ensure safe vehicle operation

Since long term testing cannot be used within the vehicle development process – waiting months and months to get meaningful results – the life cycle events have to be condensed significantly.

Therefore all car manufacturer developed so-called proving grounds and accelerated test strategies giving the capability to shorten the time for durability testing. While road testing relies on the availability of complete vehicles these tests are pretty costly.

Regarding the complex requirements on functions and save life time the wheel related components are in the main focus of LBF since many years.

As wheels and hubs are relevant for operational safety, these parts must not fail and lead to an accident. Traditionally, life cycle testing of the vehicle and its main components was carried out on the road. Since endurance tests cannot be used within the vehicle development process - waiting months and months to obtain meaningful results - the life cycle events must be significantly condensed.
For this reason, all automobile manufacturers have developed so-called test sites and accelerated test strategies that make it possible to shorten the time required for life cycle testing. While on-road testing depends on the availability of complete vehicles, these tests are quite costly.
Consequently, the improvements in the design and control of multiaxial test bed hardware that began in the 1960s have been used to develop strategies for accelerated life testing through laboratory road simulation. Today, laboratory-based durability approval is performed for many subsystems and will become even more important in the future, as there are so many platform derivatives and niche products that need to be developed within an extremely short time frame.
In view of the complex requirements for functions and life cycle savings, wheel-related components except tires have been the focus of the LBF for many years.