| Lifting machinery has a broad application prospect in today’s industrial society,and its track length and track spacing are increasing,which makes the track detection and maintenance standards related to the safety of lifting machinery operation improve day by day.Domestic and foreign scholars and research institutions began to try to use mobile robot technology to replace the traditional manual detection method based on total station.When double mobile robots are used to detect the track parameters of two parallel crane tracks,such as the track span difference and height difference,it is required that the double mobile robots keep the displacement synchronous when walking on the track.In the process of mobile robot driving on the track of lifting machinery,due to the impact of mobile robot’s bumpy walking,rough track,large seam and mobile robot’s own drive system error,it is easy to produce displacement synchronization deviation,which affects the completion of the track detection task of lifting machinery.Therefore,according to the specific requirements of double mobile robots in the task of crane track detection,this paper studies the walking synchronization control method and system of double mobile robots for crane track detection,which provides theoretical and technical basis for crane track detection based on double mobile robots,and plays a very positive role in improving the degree of detection automation and detection accuracy.The main research contents and conclusions are as follows(1)The overall design of walking synchronization control system for dual mobile robots.Combined with the working environment of crane track detection,this paper designs the overall scheme and structure of crane track automatic detection system based on dual mobile robots,and defines the detection items and requirements.Furthermore,according to the requirements of the overall scheme of track detection,the performance requirements of the dual mobile robot walking synchronization control,such as the adjustment time,the maximum deviation of displacement synchronization and the steady-state deviation,are defined,and the scheme of the dual mobile robot walking synchronization control system is designed.(2)Research on cross coupling synchronization control method of double mobile robots based on single neuron PID controller.Based on the analysis of the characteristics of the mobile robot walking on the crane track and the driving system of the mobile robot,the mathematical model of the dual mobile robot walking system is established,and the overall framework of the dual mobile robot walking synchronization control system is designed by using the cross coupling synchronization control method.The single neuron PID controller is used to improve the PID displacement controller in the traditional cross coupling synchronous control method.According to the actual working condition of the mobile robot,the impact signal at the track joint is simulated as pulse signal,and the track friction disturbance is simulated as random disturbance.The results show that: compared with the traditional cross coupling synchronization control,under impulse response,the regulation time of the cross coupling synchronization control based on single neuron PID is 1.78 s,which shortens 0.41s;Under the random white noise response,the regulation time of the cross coupling synchronization control based on single neuron PID is 1.92 s,which shortens0.42 s,and the steady-state deviation of the system is 5.8mm,which reduces 1.7mm.However,the steady-state deviation of the synchronization system still needs to be improved,and the synchronization deviation still needs to be compensated.(3)Research on synchronous compensation method of double robot walking displacement deviation based on BP neural network.BP neural network adaptive characteristics and PID control are combined to improve PID synchronous compensator in traditional cross coupling synchronous control method.The cross coupling synchronization control method based on BP neural network synchronous compensator is designed.The simulation model of control system is built by using Simulink.Compared with the cross coupling control method based on single neuron PID,the cross coupling control method based on BP neural network synchronous compensator has1.36 s adjustment time and 0.42 s reduction under impulse response;Under the random disturbance white noise response,the adjustment time is 1.51 s,which is shortened by0.41 s,and the steady-state deviation is 3.6mm,which is reduced by 3.9mm.The system stability and adjustment speed are improved,which meets the requirements of the dual mobile robot walking synchronous control system for the adjustment time and steadystate deviation.(4)Design and performance test of walking synchronization control system for dual mobile robots.Firstly,according to the overall scheme,the software and hardware of the dual mobile robot walking synchronization control system are designed,and the experimental platform of the dual mobile robot walking synchronization control system is built.The double mobile robots are allowed to walk on the standard crane track at the rated speed of 0.3m/s,and the verification test of walking synchronization control method and walking synchronization performance test are carried out respectively.The test results show that: the cross coupling synchronization control method based on single neuron PID control and BP neural network synchronous compensator,when passing through the track joint,the synchronization control adjustment time is 1.73s;When the track roughness is constantly changing,the synchronous control adjustment time is 1.77 s,and the steady-state deviation is 15 mm,which can better meet the requirements of dual mobile robot walking synchronous control for crane track detection,and achieve the expected effect. |
