37.4s。The optimal design was made on the parameters of the robot framework and structure according to the growth distribution space of eggplant. A joint type robot with 4-degree freedom for fruit and vegetable picking was developed. The fixed bilateral threshold based histogram was adopted to split the G—B gray images.To meet the vision requirement of the fruit and vegetable picking robot, the object’s characters, such as outline, area, center of gravity, enclosing rectangle and the point of cutting off, were picked up. The performance test on the whole machine was done on the robot system with the method of single camera and two-step measuring distance, which shows that the measure error is within ±18mm when the measure distance ranges from 275mm to 575mm. The system runs smoothly and reliably. The success ratio of picking is 89% and the average time consumed is 37.4s.