With high efficiency, rotary milking robot has been widely used in dairy farms. However, the current design of milking robot cannot meet the demands of personalized farms, because the scale and milking efficiency of various farms have great differences. A novel parametric structural design method for rotary milking robots is firstly proposed to address this issue. Specifically, by studying the parametric mapping relationship between the requirements of personalized dairy farms and the structural characteristics of milking robots, a new design method of adaptive parametric turntable milking robot is proposed. This method can be flexibly adapted to the design of milking robots in different scale dairy farms. Secondly, the cooperative relationship between the milking manipulator and the turntable is studied, and an adaptive milking mode is proposed. The operation and matching principle of the mode are described in detail. Finally, the digital simulation experiment platform is built. The experimental value of the rotary milking robot is within 2% of the theoretical size error, and the optimal manipulator milking mode is verified for different turntable scales.