<p>Aiming at the difficulty that robotic grinding and polishing technology is hard to achieve high-precision machining on complex curved parts such as turbine blades and aero-engine blades, this study proposes a velocity-deterministic robotic grinding and polishing method for turbine blades based on hybrid B-spline curves. By utilizing the characteristic differences of B-spline curves with different orders, the surface curvature of the blade is analyzed, and cubic and quintic B-spline curves are fitted for high and low curvature regions respectively to improve the smoothness of the trajectory curve. A cumulative arc length-curvature-velocity relationship model is systematically established. By sharing the parameters of B-spline curves and assigning a predefined velocity distribution, flexible regulation of velocity is realized, which significantly improves the robustness of the robotic grinding and polishing system and the blade machining accuracy, thus achieving the goal of velocity-deterministic polishing. Through simulation and experimental verification, the velocity data of the robot in the workpiece coordinate system (Wobj) during grinding and polishing are recorded, and a comparative analysis is conducted on the profile error and surface roughness of the polished steam turbine blade. The experimental results show that both the profile accuracy and surface quality of the steam turbine blade are significantly improved.</p>