Abstract: A sensor apparatus is provided for measuring within a region of a conduit for guiding a flow. The apparatus includes a transducer arrangement disposed at least partially around an external surface of a wall of the conduit and having one or more driver elements for exciting in operation a helical acoustic wave propagation within the wall of the conduit for leaking acoustical energy from the helical acoustic wave propagation over an extensive area of the wall of the conduit for stimulating waves in chordal paths within the flow, wherein the waves in the choral paths within the flow reenter the wall of the conduit to propagate further as a guided helical wave. The transducer arrangement includes one or more sensors for receiving a re-entered portion of the acoustic wave propagation along the paths within the flow which interacts with the flow and includes information characterizing properties of the flow.

Abstract: A sensor apparatus is provided for measuring within a region of a conduit for guiding a flow. The apparatus includes a transducer arrangement disposed at least partially around an external surface of a wall of the conduit and having one or more driver elements for exciting in operation a helical acoustic wave propagation within the wall of the conduit for leaking acoustical energy from the helical acoustic wave propagation over an extensive area of the wall of the conduit for stimulating waves in chordal paths within the flow, wherein the waves in the choral paths within the flow re-enter the wall of the conduit to propagate further as a guided helical wave. The transducer arrangement includes one or more sensors for receiving a re-entered portion of the acoustic wave propagation along the paths within the flow which interacts with the flow and includes information characterizing properties of the flow.

Abstract: In an embodiment, a method and system are provided for determining a pedestrian position via dead reckoning on a portable device carried by the pedestrian (or “user”). The device has at least a processor, a 3D accelerometer, and a 3D gyroscope. The 3D accelerometer, and a 3D gyroscope are sampled to calculate device orientation, and then 3D accelerometer samples are gathered during a sensor time frame and an average step frequency is calculated. The user's speed and direction of movement are estimated and a device velocity is calculated relative to a prior device velocity via dead-reckoning. The estimated device velocity is corrected for drift and the pedestrian position is calculated based on the corrected estimated current device velocity.

Abstract: In an embodiment of the disclosed principles, a strap down integration (SDI) system includes a gyroscope that provides gyroscope data samples and an accelerometer that provides accelerometer data samples. A timing capture module associates a timestamp in a common time-base to data samples, and an SDI module linked to the timing capture module processes the timestamped data samples to produce orientation and velocity increments. In an embodiment, the SDI system also includes a priority buffer for storing the data stream produced by the timing capture module prior to provision of the data stream to the SDI module. The SDI module may output SDI motion increments at a time specified in an output request via an output request sample placed in the incoming data stream and having a timestamp in the common time-base.

Abstract: A method of tracking the motion of a moving object having a plurality of linked segments is provided. The method uses a limited set of sensing units that are coupled to one or more of the segments to receive one or more sensor signals from the sensing units. Based on the sensor signals, the method estimates a 3D orientation and predicts a 3D position of the segments at a tracking module. The method further communicates the 3D orientation and the 3D position of the segments to a database module, and associates a pose of the object to the 3D orientation and the 3D position of the segments.

Abstract: A sensor apparatus is provided for measuring characteristics of a wall of a structure and/or a medium in contact with the structure, wherein the sensor apparatus includes a transducer arrangement disposed at least partially around a planar or curved surface of a wall of the structure, or disposed over a region of a planar or curved surface of a wall of the structure. The sensor apparatus includes a transducer waveguide including at least one free distal end whereat one or more driver and/or receiver elements are mounted on one or more sides of the at least one free distal end. Moreover, the transducer arrangement is operable, when interrogating the structure to perform at least one of: switching between selected acoustic wave modes present in an acoustic wave propagation, steering an acoustic propagation direction of the acoustic wave propagation.

Abstract: An integrated inertial motion capture system includes external position aiding such as optical tracking. The integrated system addresses and corrects misalignment between the inertial (relative) and positioning reference (external) frames. This is especially beneficial when it is not feasible to rely on magnetometers to reference the heading of the inertial system. This alignment allows effective tracking of yaw in a common reference frame for all inertial sensing units, even those with no associated positional measurements. The disclosed systems and methods also enable an association to be formed between the inertial sensing units and positional measurements.

Abstract: An integrated inertial motion capture system includes external position aiding such as optical tracking. The integrated system addresses and corrects misalignment between the inertial (relative) and positioning reference (external) frames. This is especially beneficial when it is not feasible to rely on magnetometers to reference the heading of the inertial system. This alignment allows effective tracking of yaw in a common reference frame for all inertial sensing units, even those with no associated positional measurements. The disclosed systems and methods also enable an association to be formed between the inertial sensing units and positional measurements.

Abstract: A technique for calculating magnetic field information from a magnetic sensor employs a sensing unit containing the magnetic sensor and another sensor capable of providing a measure of change in orientation. The method includes sampling a magnetic field at points in time and sampling the other sensor at each point in time. The method then entails rotating to a common time instant the magnetic field samples using the orientation of the sensing unit estimated by means of the other sensing modality in order to eliminate variations between magnetic samples due to changes in orientation of the sensor unit within such time interval. The magnetic samples, corrected for the sensor rotation in such interval, are used to calculate magnetic field related information specific to the given time interval and the magnetic field related information is communicated to a receiver at a rate lower than the sample rate.

Abstract: A system and method of communicating efficiently and reliably between a sensor unit and a master unit, especially in a wireless system, is provided. The disclosed techniques require only minimal processing by the sensor unit for communications purposes and as such, the described system and method can be implemented in systems with tight constraints on the sensor unit side in terms of required memory, power consumption, and cost, such as in wearable sensor systems.

Abstract: A sensor apparatus is provided for measuring within a region of a conduit for guiding a flow. The apparatus includes a transducer arrangement disposed at least partially around an external surface of a wall of the conduit and having one or more driver elements for exciting in operation a helical acoustic wave propagation within the wall of the conduit for leaking acoustical energy from the helical acoustic wave propagation over an extensive area of the wall of the conduit for stimulating waves in chordal paths within the flow, wherein the waves in the choral paths within the flow re-enter the wall of the conduit to propagate further as a guided helical wave. The transducer arrangement includes one or more sensors for receiving a re-entered portion of the acoustic wave propagation along the paths within the flow which interacts with the flow and includes information characterizing properties of the flow.

Abstract: A system and method for accurately estimating orientations between inertial sensing units and the body segments of a multi-segment subject to which they are affixed, and for accurately estimating position vectors from sensing units to joint centers of the corresponding body segments. By using the disclosed system and method magnetometers are not required and SDI (strap down integration) increments may be used as input to estimate the position and orientation of the sensors.

Abstract: A method of tracking the motion of a moving object having a plurality of linked segments is provided. The method uses a limited set of sensing units that are coupled to one or more of the segments to receive one or more sensor signals from the sensing units. Based on the sensor signals, the method estimates a 3D orientation and predicts a 3D position of the segments at a tracking module. The method further communicates the 3D orientation and the 3D position of the segments to a database module, and associates a pose of the object to the 3D orientation and the 3D position of the segments.

Abstract: A method, controller and system in accordance with various aspects of the present disclosure facilitate reduced energy consumption in a motion sensing device having an inertial measurement unit (IMU), with a strap down integration unit, and an application processing unit (AP). The system and method include rounding velocity increments and orientation increments at the inertial measurement unit, thereby producing a remainder values. The remainder values are added to subsequent velocity increments and orientation increments prior to rounding of those values, and so on. In this way, while motion granularity is slightly decreased, there is no drift of integration errors over time.

Abstract: A method, controller and system in accordance with various aspects of the present disclosure facilitate reduced energy consumption in a motion sensing device having an inertial measurement unit (IMU), with a strap down integration unit, and an application processing unit (AP). The system and method include sensing acceleration values and rotational values at the IMU and converting the sensed acceleration and rotational values into velocity and orientation increments by strap down integration. The velocity and orientation increments are stored in a first buffer at the IMU between updates to the AP. When an update request is received at the IMU from the AP over an interrupt link, the buffer contents are transmitted over a serial link from the IMU to the AP.

Abstract: A method of enabling a wireless communication between a master unit and at least one sensor unit is executed within a frame, the sensor unit having an internal data sampling frequency and being adapted to store samples with corresponding sample sequence numbers. The sensor unit transmits an integrated value to the master unit. The master unit transmits, during a master unit portion of the frame, a data update request message comprising an initial sample sequence number from which integration by the at least one sensor unit has to be carried out. The sensor unit integrates the sample values from the initial sample sequence number to a current sample sequence number and then transmits the integrated sample value and the current sample sequence number. The master unit receives the integrated sample value and current sample sequence number and stores at least the current sample sequence number.

Abstract: A technique for calculating magnetic field information from a magnetic sensor employs a sensing unit containing the magnetic sensor and another sensor capable of providing a measure of change in orientation. The method includes sampling a magnetic field at points in time and sampling the other sensor at each point in time. The method then entails rotating to a common time instant the magnetic field samples using the orientation of the sensing unit estimated by means of the other sensing modality in order to eliminate variations between magnetic samples due to changes in orientation of the sensor unit within such time interval. The magnetic samples, corrected for the sensor rotation in such interval, are used to calculate magnetic field related information specific to the given time interval and the magnetic field related information is communicated to a receiver at a rate lower than the sample rate.

Abstract: The described principles provide a method and system for calibrating an UWB RF positioning system. Means for automated calibration of the UWB RF positioning system allow calibration based on simple user input that does not require accuracy. Thus, the disclosed calibration means enables nomadic deployment of UWB RF positioning systems by enabling fast and easy calibration and re-calibration of the system based on in-use data to correct for changes in the system during use. Furthermore, in an embodiment of the invention, means are provided for direct feedback of calibration accuracy to the user. In a further embodiment of the invention, the full use of a UWB positioning system is enabled by obtaining optimal accuracy even at the outskirts of the tracking space and by providing optimal accuracy for a given number of receivers.

Abstract: A method, controller and system in accordance with various aspects of the present disclosure facilitate reduced energy consumption in a motion sensing device having an inertial measurement unit (IMU), with a strap down integration unit, and an application processing unit (AP). The system and method include sensing acceleration values and rotational values at the IMU and converting the sensed acceleration and rotational values into velocity and orientation increments by strap down integration. The velocity and orientation increments are stored in a first buffer at the IMU between updates to the AP. When an update request is received at the IMU from the AP over an interrupt link, the buffer contents are transmitted over a serial link from the IMU to the AP.

Abstract: A method, controller and system in accordance with various aspects of the present disclosure facilitate reduced energy consumption in a motion sensing device having an inertial measurement unit (IMU), with a strap down integration unit, and an application processing unit (AP). The system and method include rounding velocity increments and orientation increments at the inertial measurement unit, thereby producing a remainder values. The remainder values are added to subsequent velocity increments and orientation increments prior to rounding of those values, and so on. In this way, while motion granularity is slightly decreased, there is no drift of integration errors over time.