Systems and methods for determining a length and/or a diameter of a conduit

A system comprising:

• a respiratory therapy system including:
• a respiratory therapy device configured to supply pressurized air;
• and
• a user interface coupled to the respiratory therapy device via a conduit, the user interface being configured to engage the user and aid in directing the supplied pressurized air to an airway of the user;
• a memory device storing machine-readable instructions;
• and
• a control system coupled to the memory device, the control system including one or more processors configured to execute the machine-readable instructions to:
• generate acoustic data representative of at least one or more reflections of an acoustic signal in the conduit, the one or more reflections being indicative of a length of the conduit, a diameter of the conduit, or both the length of the conduit and the diameter of the conduit;
• and
• analyze the acoustic data to determine the length of the conduit, the diameter of the conduit, or both the length of the conduit and the diameter of the conduit, wherein to analyze the acoustic data, the one or more processors of the control system are configured to execute the machine-readable instructions to:
• produce a frequency intensity signal from the acoustic data, the frequency intensity signal representing an intensity of the one or more reflections of the acoustic signal across a frequency band;
• select a portion of the frequency intensity signal expected to include the resonant frequency of the conduit;
• calculate a transform of the selected portion of the frequency intensity signal to generate a wave period intensity signal;
• extract a resonant frequency of the conduit from the wave period intensity signal;
• and
• determine the length of the conduit based at least in part on the resonant frequency of the conduit.