Raspberry Primocane Bundling and Taping Mechanisms

In red raspberry production, two-year-old canes (called floricanes) are pruned and new one-year-old canes (called primocanes) are bundled and tied together to provide a firm canopy structure for the next year's production. These processes are currently manual, labor-intensive, and costly. Pruning, bundling, and tying cost farmers more than $1,482 ha(-1) year(-1), the majority of which is spent on bundling and tying. Although some mechanized techniques are available for tying the branches of fruit trees and vines, and for baling leaves and straw, research on the development of mechanized systems for managing cane berry plants has not been reported yet. In this work, a taping mechanism was designed and fabricated for tying bundles of red raspberry canes. This taping mechanism was integrated with a hydraulically controlled cane bundling mechanism for field evaluation. The taping mechanism consisted of a tape wrapper wheel, a tape holding arm, and a tape cutting assembly, whose motions were timed in proper sequence to complete the tape wrapping process. The rotation of the wrapper wheel wound the tape around a bundle of primocanes gathered by the bundling mechanism. After a predefined number of wrappings, the cutting assembly was actuated to sever the tape, and the mechanism released the bundled plant. Field testing demonstrated a bundling success rate of 94%; of 249 canes targeted for bundling, 235 were properly bundled. Of the 92 tape wrapping attempts, 76 were successful in taping bundles of canes, a success rate of 83%. The prototype system was fabricated and evaluated for its functionality without optimizing for speed. Currently, this system requires similar to 3 min per taping (compared to similar to 30 s for manual taping). Although some improvements in the size, speed, and design of the mechanisms are essential to increase the overall accuracy and productivity of the system, the results showed good promise toward the development of an automated machine for red raspberry cane bundling and taping.