High-precision modeling and simulation of the taper leaf spring of tandem suspension of commercial vehicles

The taper leaf spring of tandem suspension of commercial vehicle is different from the traditional taper leaf spring. Thus, the professional software MSC.ADAMS/CHASSIS leaf spring, which is specially applied in traditional leaf spring, does not reliably develop the computational model of the taper leaf spring of tandem suspension. The multi-body dynamic model of the taper leaf spring of tandem suspension, which is developed in this paper, is a secondary development model that is based on the leaf spring model built by MSC.ADAMS/CHASSIS leaf spring. End contact and friction in the modified model are redefined to exhibit the hysteretic characteristics of the taper leaf spring of tandem suspension. The test of the taper leaf spring of tandem suspension is conducted to validate the reliability of the modified model. The tests in this paper are divided into two groups. The first group started at an unloaded state at an excitation frequency of 1/30 Hz and amplitude of 70 mm to acquire quasi-static behavior. The second group is conducted at various frequencies (2, 3 and 4 Hz) and various amplitudes (+/- 1, +/- 3 and +/- 10 mm) in a loaded state to acquire dynamic behavior. A formula to calculate dynamic spring rate for leaf spring is proposed, and details about the formula are presented. The simulations are conducted under the same conditions as the test. The hysteretic characteristics and the relative error of dynamic spring rate from the test are compared with the ones from the simulations for the validation of the reliability of the modified model.