A system for a vehicle includes a trio of ultrasonic sensors, and a controller configured to, responsive to a location of an object identified from a distance between the ultrasonic sensors, a receive time at each of the ultrasonic sensors associated with a same ultrasonic pulse from a transmitter of the object, and an absence of data regarding a send time of the ultrasonic pulse, steer the vehicle to the object.

A system for a vehicle includes a trio of ultrasonic sensors, and a controller configured to, responsive to a location of an object identified from a distance between the ultrasonic sensors, a receive time at each of the ultrasonic sensors associated with a same ultrasonic pulse from a transmitter of the object, and an absence of data regarding a send time of the ultrasonic pulse, steer the vehicle to the object.

A sensor positioning device includes an inter-sensor distance measurement jig that measures a distance between two sensors, and is a reference when setting the distance between the two sensors to a target distance, and reference-setting jigs of sensor height position, each including a weight and a weight suspension member, a lengthwise direction of which is in a vertical direction when the weight is suspended, and each performing setting of a distance which is a total of a vertical direction dimension of the weight, a length of the weight suspension member, and a distance from an upper end of the weight suspension member to the sensor such that the distance coincides with a target height of the sensor, when the weight is in contact with a reference surface, in a state where the weight is attached to a sensor holding jig by the weight suspension member.

A sensor positioning device includes an inter-sensor distance measurement jig that measures a distance between two sensors, and is a reference when setting the distance between the two sensors to a target distance, and reference-setting jigs of sensor height position, each including a weight and a weight suspension member, a lengthwise direction of which is in a vertical direction when the weight is suspended, and each performing setting of a distance which is a total of a vertical direction dimension of the weight, a length of the weight suspension member, and a distance from an upper end of the weight suspension member to the sensor such that the distance coincides with a target height of the sensor, when the weight is in contact with a reference surface, in a state where the weight is attached to a sensor holding jig by the weight suspension member.

A method for detecting a position of a mobile body moving on a plane includes setting X-axis and Y-axis direction reference lines on the plane, disposing a dummy mobile body on intersection points of the reference lines, detecting a position of the dummy mobile body, determining position variation amounts at the intersection points as an X-axis direction error and a Y-axis direction error based on a difference from true position data, determining X-axis and Y-axis direction error approximate formulas based on the errors to calculate errors at each position on the reference lines, detecting the position of the mobile body, correcting acquired detected X-Y coordinate data by a linear interpolation method using the X-axis and Y-axis direction error approximate formulas, and obtaining position data close to the true position of the mobile body.

A method for detecting a position of a mobile body moving on a plane includes setting X-axis and Y-axis direction reference lines on the plane, disposing a dummy mobile body on intersection points of the reference lines, detecting a position of the dummy mobile body, determining position variation amounts at the intersection points as an X-axis direction error and a Y-axis direction error based on a difference from true position data, determining X-axis and Y-axis direction error approximate formulas based on the errors to calculate errors at each position on the reference lines, detecting the position of the mobile body, correcting acquired detected X-Y coordinate data by a linear interpolation method using the X-axis and Y-axis direction error approximate formulas, and obtaining position data close to the true position of the mobile body.

A system for determining the location of a mobile receiver unit includes static transmitter units, each including a respective clock which it uses to transmit a positioning signal according to a respective transmission schedule. The mobile receiver unit receives a positioning signal from any of the static transmitter units. A first processing means uses information relating to the received positioning signal to determine the location of the mobile receiver unit. A second processing means uses information relating to a respective drift and/or offset of each of the clocks of the static transmitter units to generate transmission schedules for the static transmitter units. Each transmission schedule instructs a respective static transmitter unit to transmit a positioning signal at one or more scheduled times according to the clock of the static transmitter unit.

A system for determining the location of a mobile receiver unit includes static transmitter units, each including a respective clock which it uses to transmit a positioning signal according to a respective transmission schedule. The mobile receiver unit receives a positioning signal from any of the static transmitter units. A first processing means uses information relating to the received positioning signal to determine the location of the mobile receiver unit. A second processing means uses information relating to a respective drift and/or offset of each of the clocks of the static transmitter units to generate transmission schedules for the static transmitter units. Each transmission schedule instructs a respective static transmitter unit to transmit a positioning signal at one or more scheduled times according to the clock of the static transmitter unit.

A method and apparatus for automatic gain control in a frame-aware pulsed ranging system is disclosed. A frame covers a period of time, and locationing pulses are emitted once per frame. The pulses are detected by a mobile unit with a microphone, which is able to trilaterate its physical position. To counteract false positives from reverberations of pulses emitted in prior frames, a noise threshold function declines over the course of the frame. As such, small amplitude locationing pulses received late in a frame are still detected because the small amplitude pulse exceeds the decayed noise threshold function. In this way, the noise threshold function is a filter that may detect high amplitude pulses early in a frame as well as small amplitude pulses late in a frame without detecting reverberation pulses early in a frame as false positives.

A three-dimensional control system includes an input device, a computing device, and a tracking assembly. The input device can include an input sensor, an inertial measurement unit sensor, and an ultrasonic speaker. The tracking assembly can include a plurality of ultrasonic microphones and an inertial measurement unit disposed on or with the computing device. The plurality of ultrasonic microphones can include three microphones in a first plane and at least one other ultrasonic microphone disposed out of the first plane. The ultrasonic microphones can be configured to detect ultrasonic waves output by the speaker of the input device and the computing device can triangulate the position of the input device relative to the computing device in space.