| The Cutting process of stalk is closely related with its physical and mechanical properties, cutting mode and cutting speed. This influences energy consumption of harvesting machinery directly and is an important cause of blade material abrasion. So, the mechanical properties of cotton stalk such as shear strength, compressing strength and bending strength were investigated with a computer controlled electronic universal testing machine. The results provided a theoretical reference for optimum design of cutting tool parameters and for harvesting efficiently cotton stalk. At the same time, a reciprocating cutting test bench was developed; the process of cutting stalk at different cutting modes and different parameters such as cutting speed, feeding speed, cutter type and cutter inclination could be simulated with this test bench. By the experiments, the optimum results were achieved. The main content was listed as following.The mechanical properties of cutting, compressing and bending the harvest time cotton stalk with the Computer Controlled Electronic Universal Testing Machine were experimented. The results showed moisture content of the cotton stalk was one of the important factors affecting its mechanical properties such as compressive strength, shear strength, bending strength, etc. When the sample moisture content was ranging from 30% to 50%, the compressive strength and shear strength of the bottom and middle of cotton stalk were lower. Those were in the limits of 1.66～3.13 MPa and 0.74～1.12 Mpa respectively. The bending strength of sample decreased with increasing the moisture content and it was in the limit of 4.2～5.08 MPa. In the experiments of cutting, compressing and bending, the cost power was during 2.98～4.32 J, 2.91～4.34 J, and 1.51～4.18 J respectively. And it was proper to harvest the cotton stalk when its moisture content was 30%-50%.The reciprocating cutting test bench simulating the cutting harvest of cotton stalk was developed. It mainly consisted cutter platform, acquisition system of mechanical parameters, stalk conveyer and so on. The cutter platform, accomplishing arbitrary adjust of cutter inclination from 1°to 15°and alteration of different type cutters ,was composed of framework, transmission system, crank-connecting rod mechanism, cutting machine, conveyer belt, reel and so on. The stalk conveyer comprised framework, conveyer chain, cross beam, plant holding equipment, transmission system and so forth. The distance between it and the cutter platform was free to adjust. So the conditions of different row distances and plant distances in field could be simulated by changing position of cotton stalk clamp in the conveyer chain. CZL-3E force transducer, torque transducer, variable-frequency motor and industrial control computer constituted the acquisition system of mechanical parameters. System software, having good operability and GUI, was developed by LabVIEW. And the continuously tunable feeding and cutting speed, automatic acquisition and real-time display of cut torque and force changing curves in the process of cutting were accomplished.The factors affecting stalk cutting with the self-regulating reciprocating cutting test bench were studied. From the experiments, we could conclude the work parameters, cutting speed, blade type, moisture content of cotton stalk and the angle of cutting platform all influenced cutting performance. And a group of better work parameters was cutting speed of 0.6 m/s, standardⅤblade type, moisture content of 30.2%, and cutting platform angle of 13°.
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