Ultrasonic ranging state management for unmanned aerial vehicles

An unmanned aerial vehicle, comprising:

• a first transducer that transmits first ultrasonic signals and receives first ultrasonic responses to the first ultrasonic signals;
• a second transducer that transmits second ultrasonic signals and receives second ultrasonic responses to the second ultrasonic signals or receives the first ultrasonic signals;
• and
• a signal processor that controls the transmission of the first ultrasonic signals from the first transducer and the second ultrasonic signals from the second transducer according to a cadence, wherein the signal processor comprises:
• memory;
• and
• a processor coupled to the memory, wherein the processor is configured to:
• control operation of the unmanned aerial vehicle relative to an object detected by the first ultrasonic signals and/or the second ultrasonic signals;
• determine that a target value included in the first ultrasonic responses is located within a ring-down window associated with the first transducer;
• and
• adjust a gain value;
• wherein the first ultrasonic responses are received using the gain value determined based on a binary search performed over a gain space.

A non-transitory computer-readable storage medium, comprising processor-executable routines that, when executed by a signal processor, facilitate a performance of operations comprising operations to:

• instruct a first transducer of an unmanned aerial vehicle to transmit a first ultrasonic signal at a first time;
• instruct the first transducer to transmit a second ultrasonic signal at a second time occurring after a period of time defined by a cadence for the first transducer has elapsed;
• receive the first ultrasonic signal with the first transducer or a second transducer;
• receive an ultrasonic response to the first ultrasonic signal using a gain value determined based on a binary search performed over a gain space;
• determine whether a target value included in the ultrasonic response is within a ring-down window associated with the first transducer or the second transducer;
• receive the second ultrasonic signal with the first transducer or the second transducer;
• increase one of a burst count or a voltage of the first transducer or the second transducer based on a speed of the unmanned aerial vehicle;
• and
• control the unmanned aerial vehicle based on the received first ultrasonic signal and the received second ultrasonic signal.