Optimization and Experimental Study of Structural Parameters of Compliant End-Effector for Robotic Cherry Tomato Harvesting

Abstract

HighlightsA compliant end-effector with nonlinear structure was proposed for robotic cherry tomato harvesting.The key parameters of compliant end-effector were optimized by response surface methodology(RSM), and the optimal parameter combination was obtained.Experiments verified the harvesting performance of the optimized compliant end-effector. For fruits of different sizes, the picking success rate reached 84.2%.The damage percentage of cherry tomato could be controlled below 4.22%, and the extrusion deformation of cherry tomato could be controlled below 3.98mm.Abstract.The harvesting performance of end-effector is very important for robotic cherry tomato harvesting. In this article, in order to obtain good harvesting performance, a compliant end-effector with nonlinear structure was proposed and its key structural parameters were optimized by response surface methodology(RSM). According to the expected results, the angle (ESA) formed by the extension segments of two compliant grippers 10° and the difference of the shape variable (SVD) 13 mm, at optimal settings, which was obtained by the addition of the length of the offset section (OSL) 1.3 mm, the angle of the inclined section (ISA) 17°, the thickness of the extension section (EST) 4.6 mm and the length of the extension section (ESL) 20 mm. Besides, experiments verified the harvesting performance of the optimized compliant end-effector. For fruits of different sizes, the picking success rate reached 84.2%. The damage percentage of cherry tomato could be controlled below 4.22%, and the extrusion deformation of cherry tomato could be controlled below 3.98 mm. Keywords: Cherry tomato, Compliant mechanism, End-effector, Response surface, Robotic harvesting.