Abstract:A kind of improved back propagation (BP) neural network method is used to study the forward position kinematics of the 3-RSR parallel mechanism. First, the inverse kinematics solutions of the 3-RSR parallel mechanism were studied based on theoretical approach, and then the improved BP neural network was adopted to train the data obtained from inverse kinematics solution. It was shown that the present method was reasonable by comparing the results obtained from Neural Network training and theoretical result. Furthermore, it could be clearly seen that both of the methods had a very high computational efficiency and avoided the complicated derivation and calculation effectively, but improved BP neural network had higher precision by comparing the improved BP neural network and ordinary BP neural network. Therefore, the improved BP neural network method is more reasonable in the field of engineering which high accuracy is necessary.