Design And Performance Analysis Of An All Terrain Mobile Target Vehicle

In order to meet the needs of practical shooting training reform,combined with the current development of shooting targets for training,a design scheme of all terrain mobile target vehicle was proposed.On the basis of the preliminary design of the whole vehicle,the steering and vertical obstacle crossing performance of the mobile target vehicle were analyzed and optimized in detail,and the main components of the target vehicle are analyzed and optimized by the combination of multi-body dynamics and finite element.The main contents are as follows:According to the demand of shooting training,the whole scheme of all terrain mobile target vehicle was put forward.Based on this,each part was designed.Combined with the situation of shooting target,the scheme of three-stage folding target was determined.Through the comparative analysis of various structure forms of mobile robot,the motion scheme of all terrain mobile target vehicle was determined.On this basis,the structure of double diagonal arm independent suspension was proposed,the main structural parameters of suspension were determined,and the optimal damping of suspension was determined based on ride comfort and safety.According to the design scheme and structural parameters,the three-dimensional model of the mobile target vehicle was established,and the basic parameters of the target vehicle were determined.Combined with the parameters of the target vehicle,the steering model of the target vehicle with three degrees of freedom was established,and an independent steering control strategy with zero sideslip angle of the center of mass was proposed.Through the establishment of high-speed and low-speed steering model,the relationship between four-wheel steering angle and vehicle speed and target vehicle structure parameters was determined.On this basis,an independent driving control strategy without tire slip was proposed to determine the required driving speed of four wheels.The results showed that the 4wis-4wid control mode could improve the steering flex-ibility of the target vehicle at low speed and the steering stability at high speed.In order to improve the vertical obstacle surmounting performance of the mobile target vehicle,the forward and rear wheel obstacle surmounting models under low and high obstacles were established respectively.According to different obstacle surmounting models,this paper discussed the difficult stages in the process of obstacle surmounting,analyzed the relationship between the driving force and adhesion required by the tire in obstacle surmounting,studied the influence of the position of the center of mass on the performance of obstacle surmounting,and determined the structural parameters and the minimum driving force required for obstacle surmounting.Combined with the analysis results,it was verified that the method of changing the load centroid position to change the vehicle centroid position could effectively improve the obstacle surmounting performance of the target vehicle.Using the method of multi-body dynamics and finite element,the dynamic structural mechanical parameters of the moving target vehicle body in the process of obstacle surmounting were studied,and the structural performance under full load torsion was analyzed.According to the results,four schemes of body structure improvement were put forward.Using the optimization method of multi-body dynamics,finite element and orthogonal test,the influence of four improved schemes on the structural performance was analyzed.Through the method of grey correlation analysis,the best combination of improvement schemes was determined,and the structure analysis of the improved body were carried out to verify the rationality of the optimization results.