Consulting Services

Testing and Understanding EQUAL, a Tire/Wheel Assembly Vibration Reducer

A series of laboratory experiments were performed to assess the ability of the product EQUAL to reduce tire vibration under a variety of axle loads and rotational speeds. The laboratory tests showed that EQUAL consistently reduced the vertical (Z-direction) vibration magnitude at the fundamental frequency (1/rev). The average disturbance reduction compared to dual plane balanced wheel assemblies was 20% in road testing, 29 % in on-vehicle acceleration dynamometer testing, and 55 % in fixed axle dynamometer testing. Further, videos taken of the product moving dynamically within a rotating tire aided in understanding the mechanism by which tire vibration is reduced. A model describing the dynamics of the particle/tire interaction mechanism was developed to predict the vibration reduction for a given operating condition.

Figure 1 EQUAL distributed inside a tire (sidewall cut away)