THE study of composite front axles, called fallaciously “independent wheels,” deals with the accelerations due to the inequalities of the road surface and with the resonance of the car caused by the vibrations thus produced. This study cannot be treated separately but must be taken as part of the complete problem of the resonance of the whole car to the road, according to Mr. Broulhiet.
Extensive experiments have confirmed that vertical suspension, road-holding qualities, coachwork resonance and the resonance of the steering gear are all interdependent. Therefore, the problem of road resonance must be dealt with as a whole, if one wishes to grasp the problem in its complexity and have that scientific backing necessary for rapid progress in the mind of the designer.
Mr. Broulhiet outlines, from personal research in this field, four basic conditions to obtain the best results. The geometry and equilibrium conditions of proposed mechanical realizations are analyzed. Comments upon the reception accorded the principles stated, by research organizations and by the public, are made.
Appendix 1 deals with Broulhiet-system shock-absorbers having damping proportional to the speed of the oscillations. Appendix 2 is devoted to statements regarding parallelogram-type independent front wheels. Appendix 3 is a “note” on independent front wheels of the slipper type.