<p>To meet the high-performance bonding requirements of large spherical crown bonded components, this study investigated the optimization of machining parameters and grinding trajectory planning for surface roughening, given the unknown relationship between surface morphology and bonding properties. Simulation analysis and shear tests were conducted to identify the micromorphology that enables optimal adhesive performance. Considering both surface roughness consistency and machining efficiency, a response surface analysis experiment was designed using grinding attitude inclination, downforce, spindle speed, and feed speed as independent variables. The optimal roughening parameter combination was determined through variance analysis of surface roughness. Finally, using the common bottom component of a launch vehicle as an example, the stress state under service conditions was analyzed, and a calculation method for the line spacing in the robotic roughening process was proposed. A hybrid trajectory planning method combining equal angle increment and equal length increment was developed to generate machining trajectories. The results demonstrate that the proposed processing method enables controlled roughening of large spherical crown bonded components and achieves high-performance bonding.</p>