Mechanism for Bundling and Tying of Red Raspberry Primocanes

In red raspberry production, two years old canes are removed every year and remaining one year old canes are bundled together to provide a firm canopy structure for next year's crop. Currently, cane bundling and tying is completed manually, which is a highly labor intensive operation. Automation and mechanization has a potential to reduce the labor use and associated cost for this field operation. There are some bundling and tying mechanisms presently available, but most of these mechanisms are designed with post-harvest agricultural products in mind. Such mechanisms have the flexibility of utilizing change in position and orientation of the products supported by dexterous manual control. However very few mechanisms exist which are capable of bundling and tying horticultural plants or canes in a growing stage in field environment. The authors present a novel mechanism designed to work in field conditions in trellised red-raspberry production system. A hydraulically controlled cane gripping mechanism was designed, fabricated and evaluated in a red-raspberry plot, along with a tape tying end-effector prototype that was fabricated using 3D printed parts. The prototype mechanism successfully bundled and tied red-raspberry plants with up to 7 canes. Improvement and further evaluation will be carried out to accommodate plants with larger number of canes.