How can 'external axes' enhance the functionality of FANUC robots?

External axes significantly enhance the functionality of FANUC robots by providing additional features that facilitate more complex movements. When robots are equipped with external axes, they can achieve motions that extend beyond their standard configuration, thus allowing for greater versatility in tasks.

For instance, adding linear or rotary motion via external axes enables the robot to reach different areas without needing to be repositioned. This capability is particularly transformative in applications such as material handling or assembly where multi-axis coordination is necessary to optimize workflow and productivity. The complexity of operations, such as synchronized movements across multiple axes, can be streamlined, enhancing the robot's performance and efficiency.

In contrast, the other options do not effectively capture the primary benefits provided by external axes. While simplifying programming can be a result of improved efficiency, it is not the primary advantage of adding external axes. Likewise, reducing the weight of the robot and limiting the operational area counteracts the purpose of enhancing functionality. Instead, external axes work to expand the robot's capabilities and flexibility in various applications.