Application Design And Study On Mechanical Elimination Torsion Suspension

Vehicles will be subjected to four constraints, which are vertical constraint,roll constraint,pitching constraint and torsion constraint. Torsion constraint will bring asymmetry load to the vehicles, and it's a disadvantageous and redundant constraint. The existing of redundant constraint will easy to cause components of high off-road vehicles (such as military and forest vehicles etc.) to emerge early fatigue wreck for dynamic stress and torsion loads by dynamic loads at uneven ground. Furthermore for the high mobility wheeled vehicles which are requested to have high off-road ability, the quality of wheel performance of grounding directly influences vehicles' running and high-speed cross-country performance. However the redundant constraint puts wheel performance of grounding at a disadvantage. So it's necessary to make a deep study to the present high off-road vehicles.Basing on the elimination torsion principle put forward by Prof. Guo Konghui, the paper researches high off-road vehicles' whole-coupling suspension system of eliminating redundant constraint combining with the subproject of National Natural Science Foundation of China—"Study on whole-coupling mechanical suspension system". The purpose is to guarantee no reducing roll & pitch rate and other performance to eliminate redundant constraint of vehicles, greatly reduce body elimination load and shock stress, improve the evenness of wheel loads, and enhance wheel performance of grounding.The main work and advancement have been done as following:The paper illuminates operating principle of mechanical elimination torsion suspension, and makes structural disposal and design for parts of elimination torsion suspension by UG. Besides, machining of parts and putting them on real car are also done.To check the body's torsion and dynamic load acted by "bad road", twist road simulation is absolutely necessary for high off-road vehicles. The paper builds a spectral property file of trapezoid shape twist road through modifying the tire property file. Though the simulation of mechanical elimination torsion and non-elimination torsion suspension on this road, wheel loads and height of mass center are measured, which validate the effects of improving vehicle performance of elimination torsion suspension.The paper builds a virtual test-bed model and a tire model adapting to test-bed simulation with force function. Though elimination torison and non-elimination torsion's simulation under roll input,pitching input and torsion input these three inputs, show that elimination torsion is only effective under torsion input. At the same time, simulation under three rugged roads says that elimination torison quantity is decided by value of torsion input and mechanical elimination torsion is useful to any rugged roads.Simulation on normal representative rugged road is also an emphases in the paper. The mathematical model in the time domain for the road disturbances which includes C level random road disturbances and arc shape discrete event road disturbances is developed. The compare of mechanical elimination torsion and non-elimination torsion suspension off-road vehicles simulation on uneven road validates elimination torsion principle of mechanical elimination torsion suspension.The simulation contrast of mechanical elimination torsion and non-elimination torsion suspension whole vehicle dynamics model proves that mechanical elimination torsion suspension can eliminate body torsion and shock on not smooth road a lot, as well as improve wheel performance of grounding and high speed off-road ability.