Identification method of cutting coal and rock load based on improved fractional Tikhonov regularization

In order to explore the effective identification method of cutting coal and rock load and realize the extraction and identification of cutting load characteristics,according to fractional calculus theory,the classical integral Tikhonov regularization is extended to fractional mode,and an improved fractional filter factor is constructed,an improved frac- tional Tikhonov regularization method and algorithm are proposed. Based on the theory of time domain method,the i- dentification model of the coal and rock load is established. The load is expressed as a series of kernel functions by the kernel function method. The measured load is expressed as the volume integral form between the input load and the response of the kernel function. The convolution equation is converted into a linear system of equations by discretization, andThe improved fractional order regularization method is used to transform the reverse process into a class of uncon- strained optimization problems,and the novel super memory gradient method is used to solve the objective function. The results show that with the increase of fractional order,root mean square error ( RMSE) and iteration number de- crease first and then increase. There are minimum RMSE and minimum iteration number. It can be judged that there is an optimal fractional order,that is α = 0. 5. At this time,the load identification effect is relatively ideal. Compared with the integer order and fractional order Tikhonov regularization method,the improved algorithm can not only retain the components corresponding to smaller singular values,but also suppress the components corresponding to larger singular values,thus which can effectively overcome the ill conditioned of load identification,and the Root mean square error (RMSE) of the identified load and the test load (RE) is 0. 418 2,0. 388 4,0. 366 5,and the number of iterations is 19,14,11,respectively,it has high accuracy,can overcome the smoothness of its solution,and the load details can be well identified. Therefore,the improved fractional regularization method has stronger anti noise and robustness in iden- tifying the load of cutting coal and rock,and provides an effective method for solving the problem of load identification of coal and rock and the problem of load identification in mine mechanical engineering.