| Along with the development of auto industry, the requisition on comfort of the automobile grows with each passing day, It already become the important problem that the automobile is designed and can't be ignored while developing the comfort of automobile ride. Having a lot of optimization study on the suspending system of seat at present. There are three kinds of optimization goals: First, the energy of importing the human body is minimum; Second, make the human body response minimum in the sensitive frequency region; Third, the acceleration root value spreading to the human body is minimum. The optimization parameter is: suspending system mass, rigidity, damping and the friction of join accessory .But in fact, it is nonsensical that the dynamic characteristic of the suspending system of seat is only considered. The impact of human mass on comfort not considered mainly, even considered, Often it is regarded as constant, this is inadvisable too. It has different weight to different the human body .This require that seat have corresponding variational parameters . i.e. the automobile seat comfort study to human body must combine the human body with seat , Namely study a" the human body - seat" system.In view of this state of development of the automobile seat,considering the need to human comfort, This text will optimize the dynamic parameter of the system of" the human body - seat" , to study the dynamic comfort of the automobile seat ride. The concrete approach is the following:1.To recognise the parameter rigidity, displacement, inherence frequency and damping .etc of the existing Model A and B seat. The measurement of static rigidity is through omnipotent testing machine of electron to make load-displacement curve of auto seat. And carries the differential on it to get its static rigidity curve. The test result shows : Only when loads of Model A are greater than 960 N, its rigidity seams a remarkable increase and satisfy design standards. The rigidity of Model B with the change of human weight throughout does not change, can't satisfy the design standards either.The recognise of inherence frequency of " the human body-seat"mainly by SD No. 380-vibration testing analysis system gathers and analyse data. By initialization displacement method gathering its the time courses of free vibrations respond and carrying on table analyse to get its inherence frequency. The test result shows : When the human weight is 1600 N, inherence frequency of " the human body-seat" system of Model A is only 2.50Hz. When the human weight is 460 N, inherence frequency of " the human body-seat" system of Model B is only 2.00Hz, and because with human weight changing rigidity of " the human body-seat" system of Model B is invariational, So when human weight is greater than 460 N, the inherence frequency of " the human body-seat" system must be smaller than 2 .00Hz. So not satisfying the designing requirement . Damp of A, B Model seat are separately by the test result0.32 and 0.27, within the range of design standards.2.The finite element analysis of the seat of Model A Because the relation of the load-displacement of the seat of Model B is linear, its rigidity does not change with change of human weight , So its optimize will not considered. The static and dynamic finite element analysis of Model A seat indicate that experiment accord with better their result, Model A seat can as the basic model be optimized.3. New-type variational rigidity seat optimization.This text regards analysis software of finite element of ANSYS as the optimized tool, and considers that it is too big to optimize the circulation body, For reducing single times of circulation time of calculating, raising optimum design efficiency , optimize body is divide into two steps and optimized. The concrete conditions are the following:?. Because there are two mains parameter to influence inherence frequency of system of " the human body - seat". Namely human mass and the spring rigidity under the corresponding load of the seat. So not consider the...
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