Research And Development Of Omni-directional Mobile Multi-dof Attitude Adjustment Vehicle

Handing carrier as the most important part of the airport ground support equipment undertake the vast majority of the ground security work.With the continuous improvement of manufacturing level,there are higher requirements for the performance indicators of the handing carrier.At present,the widely used handing carrier has some disadvantages,such as low efficiency,Poor mobility and versatility,and low level of automation.For the above problems,this paper presents a handing carrier with ultra-low chassis which can realize omni-directional movement and multiple degrees adjustment,the overall height is very low,and the handing carrier can walk freely under the wings and underbelly of the aircraft at a lower hanging position.And has the ability to move in all directions,has the strong adaptability to the narrow space.The main research contents of this paper are as follows:Firstly,according to the main technical parameters of the handing carrier,the overall design is carried out,and a kind of ultra-low chassis structure is designed,which can realize the obstacle surmounting function with the cooperation of parking device.The universal wheel is used as the carrier of omni-directional moving chassis,and give the concrete arrangement plan.After determining the overall design scheme.the parameter matching design is carried out for the handing carrier,and the relevant parts are selected.At last,the hydraulic system and electrical system are designed.Secondly,according to the proposed omni-directional motion scheme,the feasibility of omni-directional motion is verified by the analysis of omni-directional motion theory,and then the kinematics simulation analysis under multiple working conditions is carried out by ADAMS software.The analysis results show that under normal operating conditions,the handing carrier can move horizontally,vertically and spot rotation,which further verifies the omni-directional movement performance of the mounted vehicle.In the case of skidding,it has a great impact on the handing carrier,especially on the spot rotation,so it is necessary to ensure the clean working environment of the mounted vehicle.Then,according to the design index,a kind of laminated series attitude adjustment platform is designed.From the bottom to the top,there are lifting mechanism,vertical layer,pitching roll layer,and horizontal rotation layer.After the structural design of each layer is completed,the maximum thrust required by the oil cylinder in each attitude adjustment layer and the maximum load borne by the parts such as slide rail and slewing support are analyzed according to theoretical mechanics and kinematics software simulation,and finally the selection work is completed.In addition,a fast unloading multi-functional hanging tray is designed.Its bracket adopts universal design,which can adapt to various hanging objects,reduce bracket types,greatly improve the universality of hanging carrier,and finally complete the overall assembly design of hanging carrierAfter that,the finite element analysis of the designed handing carrier is carried out by using HyperWorks software.In this paper,six limit working conditions of the handing carrier were selected,and the correct load and constraint were applied to each working condition to obtain the stress and displacement nephogram of the handing carrier under each limit working condition.According to the nephogram data,the strength and stiffness of the handing carrier under each working condition met the design requirements.In addition,the free modal analysis of the handing carrier is carried out,and the natural frequencies and modes of vibration show that the handing carrier meets the design requirements.Finally,the light weight design is carried out,such as the free size optimization of the shear arm and the size optimization of the frame.After lightweight,the weight of the handing carrier was reduced by 178.52kg as a whole.It was verified again by the finite element method that the stress and displacement of the optimized handing carrier increased slightly,and the modal mode and natural frequency changed little,which still met the design requirements and completed the lightweight design goal of the handing carrier.