| This article shows a deep study of the theory on reducing excavating resistance,low-power excavating technology with the methods of theoretical analysis,experimental research and computer simulation. For the target of low power consumption to ensur the integrity of root stubble, wedge excavating shovel and picking up wheel components are designed. Finite element on the shovel is analyzed and a excavating resistance of single shovel is measured indoor soil bin, also with excavating resistance power and fresistance requency spectrum at the forward speed of 0.3~0.9m/s is obtained. The primary and secondary factors influencing on excavating resistance prower are analyzed and the most suitable combination of thoese factors of the lowest prower are obtained. Basing on experiments, this article offers a motion characteristics simulation study on computer about picking–up device and the whole machine function. Virtual prototype design and motion simulation of corn root stubble harvest which is made up of thoese two key components by wedge shovel and curved picking up finger picking-up device n are achieved,also with corn root stubble physical prototype is made and field experiments verification is completed.According to the study of corn root stubble growth characteristics,distribution pattern in spatial space and root soil composite mechanical properties,the structure parameters of corn stubble is offered and the main structure parameters for the shovel is determined.The finite element model of shovel is established, and its finite element static and dynamic mode analysis of excavating shovel when it working with soil is offered by software ANSYS. The result verified that the maximum principal stress of vertical load at shovel surface is located on the connecting nut. ,and it's natural frequency from mode one 67.414Hz to mode six 700.53Hz is obtained ,It is far from sub soiling vibration frequency 8-12Hz in normal, this result can,t damage to the shovel. Also relative motion trajectory for the tip of picking up wheel finger is analyzed, and picking characteristics of the stubble, casting stubble performance and condition is studied. Also with the angle of 105 0for no-casting picking,the lowest position angle 40 0is calculated. .Using self-made sensor, contributing to six component force resistance measuring method, the resistance of single shovel for excavating indoor bin together with resistance power for multi-factor or multi-level is measured.Then by vib'sys software, resistance frequency spectrum and numerical values of resistance power is obtained. In this paper, the interactions of Single factor and multi-factor and influence of various factors on excavating shovel power depending on orthogonal experimental expert-design software. is analyzed. The order of primary and secondary factors of lowest excavating power and is determined by installation angle,forward speed and angle of dip for the shovel surface. and the best combination factors of the lowest resistance power:forward speed is0.45m/s,installation angle is 52°and angle of dip for the shovel surface is 27.5°.Power equation is obtained. Soil bin experiment further verified the design of excavating shovel is reasonable.Harvest of corn stubble prototype is designed. using Pro/E software, the movement process simulation analysis for agencies of the corn root stubble virtual prototype is achieved and with the 3DS MAX software, virtual prototype of crop stubble harvest harvesting process is simulated , making a reference for the trial of physical prototype... |
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