The present invention concerns a design for dendritic poly polymer carriers, also known as nonlinear polymers, and their applications. The hub cover is rigidly secured to a wheel hub and maintains the axial position of the axle shaft. The latching seat includes a first surface and an opposite second surface, the first surface defines a sliding groove, a second surface defines a receiving slot. The second control unit is powered in an isolated manner from the input voltage, conveniently via a transformer constituting the signal coupler. Methods of use are also disclosed.