Design And Experimental Research On The Soil-bin Test Bed For Rotary Tiller Parts

The soil-bin test bed is an effective platform for the research and development of agricultural machinery or tillage parts.Aiming at the key technical problems in the research and development of the soil-bin test bed,this paper proposes a research on relevant design theories of the soil-bin test bed,which is theoretically significant and large in demand and other key technologies.This paper,based on the actual needs of an enterprise,developed a test platform to test the tillage resistance status of rotary tiller parts according to the principle of strain detection.The main research work is:1.For the problem that the soil-bin test bed is normally too large and energy consuming,this paper proposes a new structure of compact soil-bin test bed that combines the function of rotary tillage,soil formation,soil compaction and other functions in one.The soil-bin test bed is not too large,10 meters long and 1.5 meters wide.2.For the problem of complicated control strategy,this paper proposes a solution to adjust the depth of tillage-based servo motor electric cylinder and adjust the depth of soil compaction based on stepper motor synchronous lifting mechanism.It breaks the traditional mode of using soil-bin test bed hydraulic system to achieve depth adjustment,and simplifies the control strategy and process.3.A design concept is introduced where rotary tillage knife rolls are arranged symmetrically based on tillage parts and walking tank of one farming prototype.The structures of the soil-bin test vehicle rotary system,soil recovery systems,tillage depth adjustment system,compaction depth adjustment system and other functional modules are designed modularly.4.According to the modal analysis results of the soil-bin test bed trolley rotary suspension,chassis and other key components,the paper proposes the optimization of the rotary suspension structure using topology optimization method.The optimization results show that the natural frequency of the first rotary suspension improved from 89.05 Hz to152.39 Hz,an increase of about 71%,which can effectively avoid resonance.5.In regard to the needs of the research,this paper determines the control methods of rotary system,soil recovery system,tillage depth adjustment system,compaction depthadjustment system and other functional modules of the job,and develops the running and controlling system of soil-bin test car based on PLC and the frequency control technology.6.Combined with the tillage principle of rotary tiller parts,it proposes a tillage resistance testing program based on the principle of the strain detection,and completed the design and calibration of the octagonal ring transducer.The calibration results showed that the positive force,tangential force and moment coefficients of linear main bridge of the self-designed octagonal ring sensor are 0.999,0.9895,0.9877 accordingly.7.Based on independent research octagonal ring sensor,this paper built tillage resistance testing platform for Rotary Tiller parts,and conducted preliminary tests and analysis in an effort to verify the effectiveness of the soil-bin test bed design,the validity of the control system,as well as the feasibility of tillage load testing system.