Structural health monitoring of an escalator drive system

A structural health monitoring system comprising:

• a drive system of an escalator or moving walkway comprising:
• a first drive member;
• a second drive member operationally connected to the first drive member;
• and
• a tension member operationally connecting the first drive member to the second drive member;
• at least one first sensor configured to monitor a characteristic of the first drive member;
• at least one second sensor configured to monitor a characteristic of the second drive member;
• and
• a processor in communication with the first and second sensors and configured to measure and monitor a transfer function between the first and second drive members to determine if the structural health of the drive system is compromised,
• wherein the processor is configured to monitor a transfer function between the first and second drive members to determine if the structural health of the tension member is compromised, wherein the transfer function comprises signal averaging of signals received from the at least one first sensor and the at least one second sensor and wherein frequency domain curve fitting is employed to compensate for noise in the system.

A method of monitoring the structural health of an escalator or moving walkway drive system, the drive system includes a first drive member, a second drive member, and a tension member operationally connecting the first and second drive members, the method comprising:

• measuring a characteristic of at least one of the first and second drive members;
• determining if the structural health of the tension member is compromised based on the measured characteristic;
• and
• performing a safety response action when it is determined that the structural health of the tension member is compromised,
• wherein the measuring step comprises measuring a transfer function between the first drive member and the second drive member based on the measured characteristic, wherein the transfer function comprises signal averaging of signals received from the at least one first sensor and the at least one second sensor and wherein frequency domain curve fitting is employed to compensate for noise in the system.