Mechanical hard stops can be used to set the restrictive space of a working robot.

Mechanical hard stops can be used to set the restrictive space of a working robot.

• A. True
• B. False
• C. Only for teaching mode
• D. Only with supervisor approval

Answer: (B)

Mechanical hard stops physically bound motion, but using them to define the restrictive space of a working robot is not sufficient for safety. They stop by contact and are passive, not active safety devices; they don’t provide guaranteed, fail-safe stopping under all fault conditions, and a fault in the control system or sensors could allow unsafe motion to occur before the stop is reached. A robust safety approach uses software soft limits to bound commanded positions and safety-rated hardware and interlocks (along with emergency stops) to detect faults and bring the system to a safe state. The restrictive space should be part of a defined Safe Operating Envelope managed by the safe control system, not relied on solely for protection. The matter isn’t about teaching mode or supervisor approval; those are procedural aspects, whereas the fundamental point is about how safety boundaries are established and maintained.

Mechanical hard stops physically bound motion, but using them to define the restrictive space of a working robot is not sufficient for safety. They stop by contact and are passive, not active safety devices; they don’t provide guaranteed, fail-safe stopping under all fault conditions, and a fault in the control system or sensors could allow unsafe motion to occur before the stop is reached. A robust safety approach uses software soft limits to bound commanded positions and safety-rated hardware and interlocks (along with emergency stops) to detect faults and bring the system to a safe state. The restrictive space should be part of a defined Safe Operating Envelope managed by the safe control system, not relied on solely for protection. The matter isn’t about teaching mode or supervisor approval; those are procedural aspects, whereas the fundamental point is about how safety boundaries are established and maintained.