A golf club head according to one or more aspects of the present invention may include a main cavity having at least one auxiliary cavity and a base surface. Each of the data-processing units is redundant by the others with one and the same level of hierarchy, and all the data-processing units are connected to all the control devices and to the accessories proper to the drilling device through the electronic data-exchange lines that are redundant in a number equal to the multiplicity of the data-processing units. Alternatively, after forming a semiconductor film over a substrate, a Ni film is deposited over the semiconductor film while heating the substrate up to 450\xb0 C. Thereafter, the mold is closed, compressing the gas in the plastic material. More particularly, the present invention relates to the use of such a method or apparatus for real-time hardware applications since the method and apparatus may be utilized without matrix inversions or square root computations. The discrete bridge elements maintain rolling element in separation, provide rolling element retention within the bearing assembly, and function as a lubrication reservoir for grease lubricated bearings.