Research On Trajectory Control Of Excavator Operation

The traditional non-automated hydraulic excavator contains multifaceted objectiveconstraints. Not only the driver is required to have a higher level of operation, but also theexcavator works in rugged environment. With the introduction of mechatronics technologydevelopment as well as the need of improving the efficiency of the excavator and energyconservation, the research of automatic and semi-automatic control of hydraulic excavatorsis the development tend of construction machinery and has the technical foundation.The operating trajectory control of excavator working device is the focused directionof automatic control of hydraulic excavators study. This paper is based on the date of20-ton hydraulic excavator of Liugong. It’s hydraulic control system is modified byinstallation of computer controller, stepper motor control valves, angle sensors, etc. Proposeideas of arm mining practices, and computer-controlled electric boom and bucket controlvalve, control working device to dig at a predetermined trajectory. this paper summarizesthe main research contents are as follows:(1) Literature review and summarize trajectory control methods of excavatoroperations, strategies, hardware and software selection, and analyze the advantages anddisadvantages of various options discussed, as well as reference value.(2) Based on the structure of excavator working device, using D-H method andgeometric method for excavator working device kinematics analysis. Get the relationshipbetween the spatial position of teeth of bucket and the orientation of each joint anglevariable mathematical which is just the positive inverse solution of kinematics. and use thegeometric spaces to establish the conversion of the drive mechanism and joint anglecylinder stroke mathematical, using MATLAB programming, get the visual relationshipconversion.(3) Resume the hydraulic system control strategy, calculate the desired value ofboom and bucket by detecting the actual rotation angle arm, and the target track and cuttingconstraint. Then get the deviation of the corresponding measured values as the control input. According to the relatively independent of the boom and bucket control subsystem, use theindependent PID controllers, explain the calculation of the boom and bucket ideal anglevalue method procedure and the PID control theory discussed at the same time(4) For the characteristics of each component in the control system and needs ofsimulation control, build the mathematical model and simplify to get the appropriate model.Build the control simulation model by using software of MATLAB/SIMULINK and thenrun the simulation to verify the feasibility of method. For the general linear excavation,simulation results are that the value tipped off target trajectory maximum deviation is in60mm, the maximum deviation of the bucket cutting angle is0.5°.The results have a highcontrol accuracy and verify the feasibility of the method.