The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off betwe...The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1：5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density（PSD）, the root mean square（RMS） of weighed acceleration, peak factor, average absorbed power（AAP） and vibration dose value（VDV） are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency（z axis） is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the ＂A little uncomfortable＂ and ＂Rather uncomfortable＂. From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1：5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1：5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.展开更多
The terrain in hilly and mountainous regions is characterized by its discontinuity,constant undulations,and complex environment,leading to significant vibrations and potential tipping over of operating machinery.Tradi...The terrain in hilly and mountainous regions is characterized by its discontinuity,constant undulations,and complex environment,leading to significant vibrations and potential tipping over of operating machinery.Traditional crawler chassis face challenges when encountering uneven terrain,with one side possibly being suspended and causing tipping.This study introduces a crawler chassis with a split structure to address this issue.The split design allows for crossing obstacles on one side,enabling better adaptation to the dynamic terrain of hilly and mountainous areas,ultimately maximizing the chassis’performance.Through research,it was found that the split structure effectively prevents single-sided crawler suspension,allowing for a maximum longitudinal slope angle of 42.3°,transverse slope angle of 27.38°,and a maximum ravine width of 445 mm.The prototype testing confirmed that the chassis can handle slopes of up to 41°on both sides and 30°on one side,with a maximum ravine width of 430 mm.Considering that the typical cultivated land angle in hilly and mountainous regions ranges from 2°to 15°,the designed chassis is well-suited for driving operations in underground farmland within such areas.展开更多
基金Supported by Special Fund for Argo-scientific Research in the Public Interest,China(Grant No.201203024)National Natural Science Foundation of China(Grant No.51175498)
文摘The ride comfort experimental assessment of crawler off-road vehicle is relatively overlooked, and is expensive and difficult to execute with higher and higher ride comfort performance requirements. To trade off between precise and cost, an experimental method based on the similitude theory is proposed. Under the guidance of the similitude theory, a 1：5 crawler power chassis scale model equipped with a kind of variable stiffness suspension system is used. The power spectrum density（PSD）, the root mean square（RMS） of weighed acceleration, peak factor, average absorbed power（AAP） and vibration dose value（VDV） are selected as ride comfort evaluation indexes, and tests results are transformed via similarity indexes to predict the performance of full-scale power chassis. PSD shows that the low-order natural frequency of the vertical natural frequency（z axis） is 1.1 Hz, and the RMS, AAP and VDV values indicate the ride comfort performance of this kind of power chassis is between the ＂A little uncomfortable＂ and ＂Rather uncomfortable＂. From the results, low-order vertical natural frequency, obtained by PSD, validates that the similarity relationship between two models is satisfied, and 1：5 scale model used in experiment meets the similarity relationship with the full-scale model; consequently, the ride comfort prophase evaluation with the 1：5 scale model is feasible. The attempt of applying the similitude theory to crawler vehicle ride comfort test study decreases the cost and improves the test feasibility with sufficient test precise.
基金supported by the Basic Scientific Research Project of the Education Department of Liaoning Province(Grant No.LJ212410157007).
文摘The terrain in hilly and mountainous regions is characterized by its discontinuity,constant undulations,and complex environment,leading to significant vibrations and potential tipping over of operating machinery.Traditional crawler chassis face challenges when encountering uneven terrain,with one side possibly being suspended and causing tipping.This study introduces a crawler chassis with a split structure to address this issue.The split design allows for crossing obstacles on one side,enabling better adaptation to the dynamic terrain of hilly and mountainous areas,ultimately maximizing the chassis’performance.Through research,it was found that the split structure effectively prevents single-sided crawler suspension,allowing for a maximum longitudinal slope angle of 42.3°,transverse slope angle of 27.38°,and a maximum ravine width of 445 mm.The prototype testing confirmed that the chassis can handle slopes of up to 41°on both sides and 30°on one side,with a maximum ravine width of 430 mm.Considering that the typical cultivated land angle in hilly and mountainous regions ranges from 2°to 15°,the designed chassis is well-suited for driving operations in underground farmland within such areas.
