The present disclosure relates to a location determination system that includes acoustic transmitting devices (104), location tags (112), and a wireless mesh network (106), where the wireless mesh network uses battery-powered devices. A location tag receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. Clocks from members of the wireless mesh network are synchronized by observation of clock pairings, each clock pair formed by respective clocks in a transmitting device that transmits a message and a receiving device that receives the message. By analyzing the observed clock pairings, a best fit between the clock pairings may be determined. After selecting a reference clock, an acoustic transmission schedule may be propagated to the respective acoustic transmitting device.

A method and system for guiding a self-driving vehicle. The vehicle comprises an ultrasound-based proximity sensing system. The method comprises determining a location and an orientation of the vehicle in a predetermined coordinate system; in the vehicle, receiving a predetermined route from the traffic control unit; by a vehicle control unit, controlling the vehicle to travel along the predetermined route while estimating a vehicle travel path; receiving an ultrasound signal from a beacon having a known location in the predetermined coordinate system, wherein the ultrasound signal transmitted by the beacon uniquely identifies the beacon location; determining a relative position of the vehicle in relation to the beacon by means of ultrasound signals transmitted between the beacon and the vehicle; and determining a location of the vehicle in the predetermined coordinate system based on the determined relative position of the vehicle and the known location of the beacon.

An underwater remote locator device for tracking and positioning an object of the present disclosure can include a remote transducer system, abase transducer system, and a navigation module. The remote transducer system can be coupled to an object desired to be tracked. The remote transducer system can include a power source, processing means, acoustic receiver, and an acoustic transmitter. The acoustic transmitter can be configured to transmit a first acoustic wave in one or more directions. The base transducer system can include a processing means, a first base transducer having a first acoustic receiver, a second base transducer having a second acoustic receiver, and a third base transducer having a third acoustic receiver. Each acoustic receiver can be configured to receive said first acoustic wave from the remote transducer system.

Deployable navigation beacons can be deployed from a vehicle, such as an unmanned aerial vehicle (UAV), in an event of a loss of position or orientation of the vehicle. After deployment of the navigation beacons, the vehicle may detect locations of the navigation beacon, which may define a surface that may include surface features. The vehicle may then perform control operations based on the resolved locations. For example, UAV may maneuver to land proximate to the navigation beacons after resolving locations of the navigation beacons as a continuous surface. The navigation beacons may output a visual signal (e.g., a light), a auditory signal (e.g., a sound), and/or a radio signal. In some embodiments, each navigation beacon may include a different or unique signal.

An apparatus and method for measuring a swimmer's speed and conveying the speed to the swimmer in real time includes a plurality of ultrasonic beacons each having a transducer configured to emit ultrasonic signals in a pool or other body of water within which the swimmer is swimming. A wearable, waterproof, ultrasonic receiver worn by the swimmer, receives the ultrasonic signals and generates corresponding signal data. The receiver's microcontroller captures and uses the signal data to calculate the swimmer's position and speed in real time, and conveys this information to a wearable, waterproof, user interface device worn by the swimmer, the user interface device including a near-eye display disposed on the swimmer's googles.

Techniques for calculating a sound received at a plurality of distances from an unmanned aerial vehicle (UAV) may be provided. For example, during delivery, the UAV may be associated with a sensor to obtain first sound information that corresponds to the sound generated by the UAV. A sensor associated with a landing marker may obtain second sound information about the sound generated by the UAV during flight and delivery of a payload to a location associated with the landing marker. In embodiments, the first sound information and the second sound information may be utilized to calculate sound metrics for the sound generated by the UAV and determine the sound received at a plurality of distances from the UAV during flight.

The present disclosure relates to a location determination system that includes acoustic transmitting devices, location tags, and a wireless mesh network, where the wireless mesh network uses battery-powered devices. A location tag receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. Clocks from members of the wireless mesh network are synchronized by observation of clock pairings, each clock pair formed by respective clocks in a transmitting device that transmits a message and a receiving device that receives the message. By analyzing the observed clock pairings, a best fit between the clock pairings may be determined. After selecting a reference clock, an acoustic transmission schedule may be propagated to the respective acoustic transmitting device.

The present disclosure relates to a location determination system that includes acoustic transmitting devices, location tags, and a wireless mesh network, where the wireless mesh network uses battery-powered devices. A location tag receives acoustic signals (e.g., ultrasound signals) from an acoustic transmitting device. Clocks from members of the wireless mesh network are synchronized by observation of clock pairings, each clock pair formed by respective clocks in a transmitting device that transmits a message and a receiving device that receives the message. By analyzing the observed clock pairings, a best fit between the clock pairings may be determined. After selecting a reference clock, an acoustic transmission schedule may be propagated to the respective acoustic transmitting device.

A method and system for guiding a self-driving vehicle. The vehicle comprises an ultrasound-based proximity sensing system. The method comprises determining a location and an orientation of the vehicle in a predetermined coordinate system; in the vehicle, receiving a predetermined route from the traffic control unit; by a vehicle control unit, controlling the vehicle to travel along the predetermined route while estimating a vehicle travel path; receiving an ultrasound signal from a beacon having a known location in the predetermined coordinate system, wherein the ultrasound signal transmitted by the beacon uniquely identifies the beacon location; determining a relative position of the vehicle in relation to the beacon by means of ultrasound signals transmitted between the beacon and the vehicle; and determining a location of the vehicle in the predetermined coordinate system based on the determined relative position of the vehicle and the known location of the beacon.

An electronic fish finder transducer lifting system includes a mechanical actuating device; a transducer lifting device; an electronic fish finder attachment member, rotatably connected to the transducer lifting device, configured to attach to an electronic fish finder; and a mechanical linkage, connected to the mechanical actuating device and the transducer lifting device, configured to transfer force, applied to the mechanical actuating device, to the transducer lifting device to lift a front portion of the transducer lifting device.