Manufacturing a shoe typically requires a number of assembly steps, such as cutting, forming, assembling, adhering, and/or stitching several shoe parts together. Some methods of completing these steps, such as those that rely heavily on manual execution, may be resource intensive and may have a high rate of variability. Automated assembly has been described, however, processes and machinery used to assemble other goods may be insufficient to assemble shoes, which present a variety of challenges for stitching and other joining processes. For example, shoe uppers may include thick, dense materials that are difficult to stitch uniformly, particularly for complex shapes. Further, shoe stitching requires a relatively high degree of precision, both to maintain predictable fit and to ensure that both shoes in a pair match.
Shoe uppers may include stitching that is functional, aesthetic, or both, and failure to achieve a high degree of accuracy in the placement and uniformity of the stitching may make the shoes prone to premature failure or aesthetically unacceptable. Uniformity is desired within a given part, but also part-to-part, e.g., to make sure that decorative stitching is consistent on both shoes in a pair of shoes. Of course, functional stitching should also be uniform, e.g., to ensure that the shoe upper does not separate from the sole or tongue of the shoe, and to ensure that any separate parts of the shoe upper do not unintentionally separate from one another. At the same time, the materials used to construct a shoe upper may be susceptible to marring, abrasion, or other damage from automated equipment used to assemble goods that are highly durable or are not valued significantly for aesthetics, such as nautical tarps. Damage to the shoe upper material may be aesthetically unacceptable, or may interfere with functional properties of the shoe upper, such as permeability to moisture.
There remains a need for automated shoe assembly systems, processes, and methods which improve on the accuracy and precision of the assembly, particularly, stitching processes during assembly.