Abstract: A flexible capture locking mechanism based on cone bar docking was designed to address the issues of large structural dimensions and high collision forces in the truss assembly process of space solar power station. This mechanism uses spring rods instead of traditional rigid rods to reduce contact forces, and utilizes sliding grooves to improve space utilization and synchronization of capture locking. A simulation model of the mechanism is established, and different parameters are analyzed using ADAMS to study their impact on contact forces during the capture process. Results show that under extreme conditions, optimizing parameters such as relative friction coefficient, cone angle of the docking cone, spring rod stiffness, and docking speed reduces the contact force during the docking process to 4.5 N, achieving low disturbance docking. The research results provide greater flexibility for the in-orbit assembly of space solar power plants and are expected to play an important role in future space missions.