In this paper, the use of the inverse solution method for estimating the mass of moving load on an inclined functionally graded
material (FGM) Timoshenko beam is discussed based on the measured displacements. Fletcher–Reeves (FR) method is used
to solve the inverse problem. Also, in the process of solving the inverse problem and in order to solve the direct problem,
Newmark method is applied for discretization of the time domain and finite element method (FEM) is used for discretization
of the space domain. According to many other similar types of research, instead of conducting an experiment and measuring
displacements of the beam as inputs of the inverse solution, those inputs are obtained from the direct problem and then
random errors are added. Furthermore, an inclined functionally graded (FG) beam with different boundary conditions and
power-law exponents due to different speeds of the moving mass has been studied to evaluate the performance of the proposed
method. The accuracy of results is very high in all cases.