A user computing device for identifying a driver of a vehicle on a trip is provided. The user computing device is associated with a first vehicle occupant, and is programmed to: (i) detect a second user computing device associated with a second vehicle occupant, (ii) initiate a ping exchange process including emitting a set of non-audible sonic ping signals and detecting a set of signals from the second user computing device over a duration of the trip, (iii) generate a relative positioning map of the user computing device with respect to the second user computing device, (iv) determine that the first vehicle occupant is one of a driver and a passenger of the vehicle, and (v) transmit, to a driver identification (“DI”) server, a trip report including the determination and the generated relative positioning map.

Described herein are methods and devices for improved location of any and all underwater structures or equipment installed underwater. In particular, systems are disclosed that combine optical and acoustic metrology for locating objects in underwater environments. The systems allow for relative positions of objects to be determined with great accuracy using optical techniques, and support enhanced location of devices that utilize acoustic location techniques. In addition, location information can be provided by the system even in conditions that make optical metrology techniques impossible or impractical.

Described herein are methods and devices for improved location of any and all underwater structures or equipment installed underwater. In particular, systems are disclosed that combine optical and acoustic metrology for locating objects in underwater environments. The systems allow for relative positions of objects to be determined with great accuracy using optical techniques, and support enhanced location of devices that utilize acoustic location techniques. In addition, location information can be provided by the system even in conditions that make optical metrology techniques impossible or impractical.

A method for estimating a range of a moving target, the method including emitting, from a target, a first ultrasound signal T, wherein the first ultrasound signal T is generated based on a first differential Zadoff-Chu sequence x; receiving, at a receiver, a second ultrasound signal R, which corresponds to the first ultrasound signal T, wherein the second ultrasound signal R includes a second differential Zadoff-Chu sequence y; correlating the first ultrasound signal T with the second ultrasound signal R to calculate an initial time of flight estimate tau.sub.corr; and calculating an initial range estimate d.sub.corr by multiplying the initial time of flight estimate tau.sub.corr with a speed of sound c. A differential Zadoff-Chu sequence is different from a Zadoff-Chu sequence.

A method for estimating a range of a moving target, the method including emitting, from a target, a first ultrasound signal T, wherein the first ultrasound signal T is generated based on a first differential Zadoff-Chu sequence x; receiving, at a receiver, a second ultrasound signal R, which corresponds to the first ultrasound signal T, wherein the second ultrasound signal R includes a second differential Zadoff-Chu sequence y; correlating the first ultrasound signal T with the second ultrasound signal R to calculate an initial time of flight estimate tau.sub.corr; and calculating an initial range estimate d.sub.corr by multiplying the initial time of flight estimate tau.sub.corr with a speed of sound c. A differential Zadoff-Chu sequence is different from a Zadoff-Chu sequence.

In an embodiment, the present invention is a method for ranging which includes emitting an acoustic signal at a first frequency, monitoring for a first acoustic response signal at a second frequency, and responsive to receiving the first acoustic response signal within a predetermined amount of time, (1) calculating a first distance between a first device and a second device based on a duration between emitting the first acoustic signal and receiving the first acoustic response signal, and (2) broadcast a first message including the distance and an identifier.

A user computing device for identifying a driver of a vehicle on a trip is provided. The user computing device is associated with a first vehicle occupant, and is programmed to: (i) detect a second user computing device associated with a second vehicle occupant, (ii) initiate a ping exchange process including emitting a set of non-audible sonic ping signals and detecting a set of signals from the second user computing device over a duration of the trip, (iii) generate a relative positioning map of the user computing device with respect to the second user computing device, (iv) determine that the first vehicle occupant is one of a driver and a passenger of the vehicle, and (v) transmit, to a driver identification (“DI”) server, a trip report including the determination and the generated relative positioning map.

A user computing device for identifying a driver of a vehicle on a trip is provided. The user computing device is associated with a first vehicle occupant, and is programmed to: (i) detect a second user computing device associated with a second vehicle occupant, (ii) initiate a ping exchange process including emitting a set of non-audible sonic ping signals and detecting a set of signals from the second user computing device over a duration of the trip, (iii) generate a relative positioning map of the user computing device with respect to the second user computing device, (iv) determine that the first vehicle occupant is one of a driver and a passenger of the vehicle, and (v) transmit, to a driver identification (“DI”) server, a trip report including the determination and the generated relative positioning map.

An underwater work system of the present disclosure acquires a relative position of an underwater vehicle relative to a surface ship at the start of searching work, the relative position being measured based on a sound wave transmitted from a wave transmitter. The underwater work system calculates a position of the underwater vehicle based on the acquired relative position. When a measurement error region whose center corresponds to the calculated position of the underwater vehicle and an expected laid region of a pipeline extending in a predetermined direction overlap each other, the underwater work system moves the underwater vehicle to such a position that the measurement error region and the expected laid region do not overlap each other, and then, makes the underwater vehicle perform crossing detection in which the underwater vehicle detects the presence or absence of the pipeline while crossing the expected laid region.

An underwater work system of the present disclosure acquires a relative position of an underwater vehicle relative to a surface ship at the start of searching work, the relative position being measured based on a sound wave transmitted from a wave transmitter. The underwater work system calculates a position of the underwater vehicle based on the acquired relative position. When a measurement error region whose center corresponds to the calculated position of the underwater vehicle and an expected laid region of a pipeline extending in a predetermined direction overlap each other, the underwater work system moves the underwater vehicle to such a position that the measurement error region and the expected laid region do not overlap each other, and then, makes the underwater vehicle perform crossing detection in which the underwater vehicle detects the presence or absence of the pipeline while crossing the expected laid region.