Kinematics Analysis And Virtual Simulation For A Logging Harvester

Experiments for complex electromechanical system like engineering machinery and space robot are dangerous and expensive.During the development,the key technology is verified in the simulation environm ent.It is found by the test on the logging harvester that:during the process of the alignment of logging head and capturing trees,the operator needs a lot of observation,judgment and repeating operation,which results in the no-effect time increasing in one operation cycle;simultaneously,the re-alignment process and unreasonable action of hydraulic cylinder joints during the working process cause the losses of the fuel in the system,increase operating costs.This article presents the kinematics analysis and virtual simulation via virtual reality for the logging harvest.In details,the following contributions are contained in this dissertation:1.Manipulator kinematics of the logging harvester were researched considering simulation requirements.The forward and inverse kinematics model of the logging manipulator were established.The pose variable of harvesting head and the transformation between joint variables and hydraulic cylinder variables are obtained for the control purpose.An autonomous control method is suggested for the harvesting head to capture trunks.The logging head can move along a straight path,circular path as well as based on laser-measurement data to complete trees harvesting operations autonomously.2.Based on SolidWorks,Visual C++platform and OpenSceneGraph 3D graphics engine,a logging harvester operation virtual simulation system was developed.The virtual simulation system contains the model of hydraulic manipulator of the logging harvester.The control parameters,instructions,motion information can be set and saved.Using the system,the mission path planning and control strategies of the hydraulic manipulator are verified.3.Controllers like handle operation,steering wheel and pedals have multipath control signal.All the signal connected to the virtual model of the logging harvest via CAN bus.Each joint of the virtual logging manipulator can be controlled to realize human-computer interaction.This study is an effective way to further enhance the degree of automation and to reduce operating costs of the logging harvester.It lays the theoretical and technical foundation for the ongoing domestic logging harvester manufacturing and marketing.