Trajectory Tracking Of On-Board Spraying Manipulator And Optimization Control Of Powertrain System Of Working Vehicle

In the operation process of tranditional aerial spraying vehicle,there are some problems,such as not high trajectory tracking accuracy of spraying manipulator,low operation efficiency of the working vehicle,high fuel consumption,and serious pollution.For this reason,this dissertation focuses on the automatic trajectory tracking control of the spraying manipulator and the optimal control of the vehicle powertrain system from the perspective of practical application.In view of flexible deformation,uncertain parameters of hydraulic drive system and external disturbance during the operation of spraying manipulator,several control strategies are further investigated for the high performance of trajectory tracking of spraying manipulator to achieve the high quality of spraying.Firstly,under the consideration of the trajectory planning of the manipulator once spraying,three trajectory tracking control strategies are designed,including L₂ gain disturbance attenuation,double closed-loop active disturbance rejection control(ADRC)and sliding mode ADRC.The L₂gain disturbance attenuation control can suppress the influence of the manipulator deflection and external disturbance on the trajectory tracking performance at the L₂ gain level.The double closed-loop ADRC and sliding mode ADRC control can realize the full compensation of deflection,parameter perturbation and disturbance due to the extended state observer(ESO),which further improves the trajectory tracking control accuracy.Secondly,considering that the whole spraying process is actually a repetitive planning trajectory tracking,the spraying process of the manipulator can be regarded as a dynamic system that completes a planning trajectory tracking task and operates iteratively in a limited time interval,an adaptive iterative learning trajectory tracking control strategy is proposed,which can deal with the initial conditions of any system and the inconsistent iterative reference trajectory,so as to further improve the whole spraying quality.Based on the kinetic model of the manipulator,the optimal control method is used to reconstruct the reference trajectory in finite time,so that the manipulator can track the trajectory without resetting the initial conditions.The iterative axis and adaptive control method are used to deal with the unknown time-varying parameters of the system,and the finite time trajectory tracking convergence is realized.Aiming at the recovery and reuse of the potential energy and kinetic energy of the whole vehicle in the spraying process,the potential energy recovery system of the manipulator and the hybrid hydraulic system of the whole vehicle are designed respectively.The optimization of accumulator parameters and key components parameters of the system is studied according to the operation conditions of the manipulator.In the process of optimizing the hybrid hydraulic system of work vehicle,an improved multi-objective particle swarm optimization(MOPSO)algorithm is proposed to obtain the Pareto solution set of the system key components parameters optimization,which provides a wide choice for the design of hybrid hydraulic powertrain.In order to further improve the fuel economy of the spraying vehicle,the energy management optimization control problem is studied for the hybrid hydraulic powertrain system.Three energy management control strategies are designed,including logical-based control,equivalent fuel consumption minimization strategy with equivalent factor optimized by improved multi-objective particle swarm,and Markov-based stochastic model predictive control.Meanwhile,in the hierarchical control architecture with the upper energy management strategy based on stochastic model predictive control,the lower engine speed tracking control is considered.A speed tracking controller of engine is designed by combining model predictive control and load observer.In order to fully demonstarte the practicability and effectiveness of the proposed trajectory tracking control strategies,the designed trajectory tracking control strategies are conducted on simulation and experiment.The effectiveness and practicability of the optimized powertrain system and the three energy management control strategies are also verified by simulation software and experimental platform.