To solve the problem that the positioning accuracy of the acoustic emission time difference localization algorithm is affected by many factors such as rock wave velocity in rock mechanics test

an unknown wave velocity acoustic emission localization algorithm based on particle swarm optimization is developed in this paper. The algorithm takes the rock wave velocity as an unknown value

establishing the objective function based on the least squares principle according to the picked time difference

applying the particle swarm optimization algorithm to solve the objective function and find the target position and wave velocity. The weight coefficient is an important factor affecting the accuracy and stability of the algorithm. Firstly

the optimal weight coefficient 0.729 8 is determined by numerical model

which can satisfy the accuracy and stability requirements of the algorithm. The numerical simulation results show that the calculation accuracy based on the selected weight coefficient is higher than the traditional wave velocity algorithm. In order to verify the algorithm in practical application

the lead-breaking test is carried out. It is proved that the algorithm is superior to the traditional wave velocity algorithm.