What is a disadvantage of leadthrough programming?

• A. It can be readily learned by shop personnel.
• B. It does not require production downtime.
• C. It requires regular production downtime to program the robot.
• D. It allows programming without stopping production for trials.

Answer: (C)

Leadthrough programming teaches the robot by physically guiding its arm through the desired motions in the actual work cell. The main drawback is that this teaching step typically requires taking the production line offline. To capture the path, the operator must access the robot, position parts, and move or guide the arm, which means the cell isn’t in normal production during the teach and trial phases. That downtime reduces line uptime and can slow changeovers or frequent task updates.

Other statements—such as it being readily learned by shop personnel or not requiring downtime—don’t align with how leadthrough works in practice, since the teaching phase interrupts production and trials usually need stops for safety and verification.