Study on pressure angle optimization for cam curve of continuous zoom system based on the particle swarm optimization

In this paper, we proposed a method for optimizing the pressure angle of the cam curve in a zoom system using Particle Swarm Optimization (PSO) algorithm. This method improved the design efficiency of the cam curve and effectively solved issues such as cam motion jamming caused by excessive pressure angles. Firstly, the cam structure was analyzed based on the mechanical theory. Secondly, in the phase of the pressure angle optimization, constraints were designed and a new fitness function was introduced as an indicator to obtain the optimal solution of the nonlinearly broaden parameter of the cam curve in a multidimensional space. Finally, the zoom curve of the designed 8x optical system was optimized using the proposed method. The results showed that the maximum pressure angle of the zoom group decreased from 72.7° to 44.8°, and the maximum pressure angle of the compensation group decreased from 52.6° to 44.2°. In conclusion, this method could effectively improve the performance and lifespan of cam zoom systems, providing positive guidance for the engineering application of continuous zoom systems.