Dynamics uncertainty analysis of mine bolter manipulator

Mine bolter is an efficient and safe automation equipment in the process of modern mine roadway support, in which the manipulator is the key component to complete the support operation.The uncertainties of the dynamic system of the manipulator will be more prominent due to the factors such as processing and assembly errors, material defects, wear and tear, bad working environment in the underground and high working intensity of the operators.In this paper, the dynamics model of the manipulator is deduced based on Lagrange theory.The interval mathematics theory is introduced into the uncertainty analysis of the dynamic system of the manipulator, and the uncertainty analysis method of the dynamic system of the manipulator based on the interval mathematics is put forward.Two kinds of surrogate models, interval scanning method and tensor product method, are constructed to analyze and describe the relationship between the moment on each joint of the manipulator and the joint angle and joint angular velocity.Because the rod 2 and rod 4 of the manipulator are far from the center of gravity of the drilling rig in practical operation, the force is large and the structure is variable, the response range and efficiency of the corresponding output angle and angular velocity are studied when the moment of rod 2 and rod 4 has uncertain parameters.The results show that the time consumption of the scanning method is 0.173 4-0.288 8 times of that of the tensor product method.At the same time, the calculation results are closer to the theoretical values, with higher accuracy and smaller error, and it is more suitable for engineering practice.Finally, the dynamic response of the manipulator with uncertain parameters is studied experimentally and compared with the theoretical results.The dynamic response laws of the two systems are basically the same, which verifies the practicability and accuracy of the algorithm in this area.The study of dynamic characteristics with interval uncertainties paves the way for the control of subsequent manipulators.It also becomes a new method for predicting and judging the positioning accuracy of manipulators, and further guarantees the support effect of the manipulators on roof and sidewall.