Research On In-pipe Cutting Robot Of The New Tubular Roof Method

As a relatively novel construction method of underground excavation,the new tubular roof method has the advantages of good control of stratum deformation,high safety,and good social-economic benefits.It has broad application prospects in urban underground space development projects.However,the pipe cutting process of the new tubular roof method currently adopts the artificial carbon arc air gouging method,the environment in the steel pipe is harsh.Manual pipe cutting operation has high labor intensity,low efficiency,and poor quality.With the development of science and technology,it is the future trend to use automatic equipment instead of manual to complete the pipe cutting operation of the new pipe curtain method.This article is based on the project of the railway station tunnel under Yingze street in Taiyuan.Research on the In-pipe cutting robot used in the pipe cutting process of the new tubular roof method is carried out.The research contents and results are as follows :1.According to the engineering background and pipe cutting task requirements,the overall scheme of the In-pipe cutting robot is proposed,and the selection,design and optimization of the main parts are completed,including the model selection of industrial robot and plasma air gouging machine,the design of the working principle diagram of the hydraulic system of the support system and the design and optimization of the support frame structure.2.The kinematics model of the In-pipe cutting robot is established by using the modified D-H method,and the analytical expressions of the forward and inverse kinematics are obtained.The correctness of the analytical method is verified by MATLAB simulation.Based on the Lagrange equation,the dynamic simulation of the robot under a given trajectory is carried out by ADAMS.The simulation results prove the feasibility and safety of the cantilever installation of the industrial robot and provide strong theoretical support for the trajectory planning of the In-pipe cutting robot of the new tubular roof method.3.Based on the analysis of plasma air gouging cutting quality evaluation parameters,the mathematical optimization model of plasma air gouging cutting process parameters is established by using the response surface method.The best process parameters of cutting Q355 B steel pipes such as nozzle diameter of 4mm,angle of cutting torch of 44°,current intensity of 190 A and air gouging speed of 730mm/min are obtained.Compared with manual carbon arc gas gouging cutting pipe surface without secondary processing,the cutting efficiency of plasma gas gouging cutting pipe is increased by 64.24 %.4.Under the constraint of the optimal air gouging speed,the Cartesian space trajectory planning of the robot end is carried out based on the 5-segment S-type velocity curve.The genetic algorithm is integrated into the S-type velocity curve to obtain the time-optimal cutting trajectory under the velocity constraint.The simulation experiment is carried out on the simulation platform in MATLAB environment.The simulation results show that the optimized trajectory meets the cutting requirements.