Which of the following applies to pushbuttons and keypads in robot control?

• A. They are illegal
• B. They have no role in robot control
• C. They may be used for incremental control
• D. They can only trigger emergency stops

Answer: (C)

Pushbuttons and keypads serve as simple human-machine interfaces that translate quick human actions into discrete control signals. This setup is ideal for incremental control because each press yields a small, deliberate change in the robot’s motion or state, such as nudging a joint a tiny step, stepping through preset positions, or increasing/decreasing speed in small increments. They’re commonly used for jogging, mode selection, manual overrides, and quick testing, thanks to their clear, fast feedback. They aren’t illegal and do have a practical role in robot control, and they aren’t limited to emergency stops—emergency-stop buttons exist, but pushbuttons and keypads can trigger many different functions, not just emergencies.