Design of a Pineapple Picking End-Actuator
Physical dimension and mechanics properties of Bali pineapple samples were measured. Statistic results show size difference of vertical height is minimum, size difference of transverse diameter is maximum. For ensuring gripping stability and precision, the pineapple end- actuator was designed according to transverse diameter. Static compression test results show elastic deformation firstly occurs when the compression load is small. As the load increases to a certain extent, rupture and yield failure gradually generates. With maturity degree increase, limit compression strength reduces. Influence of maturity degree on limit compression strength is extraordinary significant. The pineapple should be harvested in time considering of maturity degree. The larger the pineapple transverse diameter is, the less the limit compression strength is. For those pineapples with same maturity degree, influence of transverse diameter variety on limit compression strength is not significant. The clamping mechanism chooses sliding-lever double-fulcrum structure. When its finger lever angle takes 35, center distance of the two fulcrum 2a is 110mm, v-shaped groove angle is 120，finger lever length takes 135 mm, clamping error requirements can be satisfied, and the optimized deflection angle is 87.6. Clamping force analysis shows that the designed picking end-actuator can ensure no damage clamping for pineapple.
Wen-Pei Sung, Jimmy (C.M.) Kao and Ran Chen
H. M. Xia et al., "Design of a Pineapple Picking End-Actuator", Applied Mechanics and Materials, Vols. 184-185, pp. 134-139, 2012