| Taking the medium-sized segmented sugarcane combine harvester developed by a certain enterprise as the research object and taking the sugarcane broken rate as the index,this paper analyzes the matching relationship between the walking speed and the cutter speed of the sugarcane combine harvester in the course of harvesting.The speed matching control is carried out to realize the coordinated linkage control of the sugarcane combine harvester,so as to ensure the harvesting efficiency of the harvester,reduce the harvest loss,improve the quality of the root and reduce the broken rate.As follows are the main contents of the study:1.Taking the sugarcane broken rate as the index,the matching test between cutter speed and walking speed is carried out,.and the optimized matching combination is obtained:When the walking speed is 1 km/h,the broken rate is the lowest when the cutter speed is 570 r/min;When the walking speed is 2 km/h,the broken rate is the lowest when the cutter speed is 620 r/min;When the walking speed is 3 km/h,the broken rate is the lowest when the cutter speed is 660 r/min.2.The signal test system is set up to collect the motor working pressure and speed signals of the key subsystems of the sugarcane harvester,and analyze the influence of the pressure and speed of each subsystem on the sugarcane broken rate.The results show that walking speed,walking pressure,cutter speed and cutter pressure have significant effects on sugarcane broken rate.3.The prediction model of sugarcane broken rate based on support vector machine(SVM)was established,and the prediction model is optimized by least square method and particle swarm optimization(PSO).The results show that the average absolute error and mean square error of the prediction model based on PSO-LSSVM are 0.145 and 0.0214 respectively.The prediction accuracy is high and the effect is good.Based on the prediction results of broken rate,the matching control strategy between walking speed and cutter speed is obtained.4.According to the requirements of cutter speed automatic matching control,three control schemes are proposed,and the simulation analysis of three control schemes is carried out by AMESim software.The results show that:The response time of mechanical-electrical-hydraulic servo pump-controlled speed regulation system is 3.8926 s,the speed adjustment time is 9.84 s,which is not suitable for the coordinated linkage control of the cutter speed;The response time of the proportional valve inlet throttle regulation system and the proportional valve bypass throttle speed regulation system are 0.7159 s and 0.8062 s respectively,and the dynamic speed adjustment time is short,respectively 1.49 s and 1.24 s,and the speed control error is within 0.1%,which can meet the fast and accurate tracking requirements of the cutter speed to the walking speed.5.The software and hardware of the coordinated linkage control system is designed and applied to the sugarcane combine harvester.Field harvest experiments were carried out and the results show that:(1)Cutter speed can be changed follow the walking speed according to the matching conditions.The speed adjustment time of the cutter is about 1.5 s,which is basically consistent with the simulation results.The maximum speed error is 3.51%,which indicates that the control system can meet the requirements of coordinated linkage control of the cutter speed of the sugarcane combine harvester.(2)After coordinated linkage control of the cutter speed of sugarcane combine harvester,the cut of sugarcane root is smooth,the cutting quality is good,and the average broken rate is 7.02%,which meet the standard that the broken rate of sugarcane harvest by machine is less than 10%. |
