Fig. 1. 3D measurement frame diagram of orange based on adaptive co-opposite-direction slicing method

Fig. 2. Point cloud data acquisition system

Fig. 3. Complete point cloud model of registered oranges in different coordinate systems

Fig. 4. Height and diameter of the orange simulation model

Fig. 5. Schematic of positive and opposite cutting of orange model. (a) Slicing from top to bottom; (b) slicing from bottom to top

Fig. 6. Schematic diagram of k-nearest neighbor concave hull algorithm (k=3)

Fig. 7. Adaptive slicing of point cloud

Fig. 8. Pictures of the orange. (a) Simulation model; (b) real orange

Fig. 9. Measurement of shape index of the orange. (a) Height; (b) D₁; (c) D₂; (d) volume

Fig. 10. Relative error of the orange shape index

Fig. 11. Calculation results of orange shape indexes under Ⅰ and Ⅱ. (a) Height; (b) D₁; (c) D₂; (d) volume