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Abstract. Robot harvesting is one of confident solutions to reduce the production cost in the labor intensive industry. In furtherance of this situation, two prototype robotic fruit picking end effectors were introduced in the previous study identifying the vacuum gripping performance with 90% and 95% of the fruit removal rate for Washington Navel (Citrus sinensis cv. Navel) (February 9th to 13th in 2013) and Hamlin (Citrus sinensis cv. Hamlin) (October 20th to November 3rd in 2014). However, it was observed during in field experiments that the end effector repeated grasping attempt in one picking cycle due to unstable initial fruit holding, incomplete fruit grasping by gripping finger and lower vacuum pressure. In this study, the third prototype end effector was developed focusing on more forceful fruit gripping performance with a less complex structural design. Four articulated grasping fingers more tangibly gripped a grapefruit with a lateral diameter from 75mm to 125mm (3~5in). Additionally, a rapid grasping recovery prevented the end effector from failed fruit grasping. Throughout experiments conducted in the research field (Plant Science Research & Education Unit in Citra, FL), the newly-developed end effector achieved a 99% fruit removal rate with 19.3~29.1N of linear pulling load from the central vacuum gripper, which has a diameter of 52.5mm.