| The all-terrain mobile robot is a general-purpose mobile platform that integrates environmental awareness,dynamic decision-making and planning,behavioural control and execution,and plays an important role in rough terrain operations such as sand,hills,and farms.At present,due to the increased demand for outdoor multi-terrain operations and the complexity of the operating terrain,ordinary mobile robots can no longer be applied.Therefore,all-terrain mobile robots are gradually becoming the most important intelligent equipment in the field of complex terrain operations.The ability to pass and adapt to complex surfaces has been the focus of study in the field of all-terrain mobile robots.The compatibility of the moment balancing mechanism and the suspension damping mechanism has an important influence on the passability and adaptability.How to optimise the design of the moment balancing mechanism based on the integration of the suspension damping mechanism and to improve the compatibility of the moment balancing mechanism with the suspension damping mechanism is still a problem that needs to be solved by researchers.The issue of compatibility is manifested in two areas: On the one hand,the introduction of the moment balance mechanism that does not consider compatibility will weaken the vibration damping effect,resulting in the suspension and tires not matching with the terrain,and the drive moment cannot be effectively converted into traction.On the other hand,simply considering the vibration damping effect will lead to poor drive moment balancing effect,resulting in imbalance in four-wheel drive,and extremely high requirements for the moment output of the drive joints.The thesis addresses the problem of optimising the compatibility of the moment balancing mechanism and the suspension damping mechanism of an all-terrain mobile robot as follows:(1)Study of the drive moment distribution mechanism of an allterrain mobile robot.All-terrain mobile robot drive moment distribution characteristics are analysed,and the drive moment distribution mechanism revealed.Specify the design direction of the moment balancing mechanism for all-terrain mobile robot.(2)Moment balancing mechanism design and M&S compatibility study.A moment balancing mechanism was designed and studied for the distribution of the drive moment of an all-terrain mobile robot,and a dynamics model based on the specific structural characteristics of the allterrain mobile robot was developed for the compatibility of the moment balancing mechanism and the suspension damping mechanism.The transmission law of road excitation between the moment balancing mechanism and the suspension damping mechanism was explored.The optimization design idea of the characteristic parameters of the torque balance mechanism and suspension damping mechanism was clarified.(3)Optimisation of the characteristic parameters of the moment balancing mechanism and the suspension damping mechanism.A hierarchical adaptive NSGA-II algorithm,which was used for the optimization of all-terrain mobile robot characteristic parameters,was proposed.The optimization results of the parameters before and after the improvement of the algorithm are obtained,and the basis for the verification experiments of the compatibility effect of the moment balancing mechanism and the suspension damping mechanism was laid.(4)Experimental research on the coordinated matching of the characteristic parameters of the moment balancing mechanism and the suspension damping mechanism.Simulation experiments and outdoor experiments were carried out to investigate the compatibility of the two mechanisms.Before and after parameter optimisation,the driving moment difference and body vertical acceleration values of the all-terrain mobile robot were obtained,verifying that the compatibility problem was coordinated and optimised.The drive moment balance and body damping are well integrated to enhance the roadworthiness and smoothness of the mobile robot.The moment balancing mechanism was designed according to the drive moment distribution characteristics,and the compatibility between the moment balancing mechanism and the suspension damping mechanism was analysed to optimise the characteristics parameters.The integration effect of the two mechanisms was verified,and the dynamics of the mobile robot are improved,laying the foundation for subsequent high-precision motion control. |
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