A method of calibrating a wearable electronic device includes providing an indication of a target speed for an activity to a user wearing the wearable electronic device and receiving location data from a location data unit during the activity. The method also includes receiving, concurrently with the location data, user stride data associated with the user during the activity and computing a speed of the user as a function of the location data as a function of time. The method further includes populating a table of the speed of the user as a function of the user stride data and calibrating the wearable electronic device in accordance with the table.

A method of determining travel speed of a user having a wearable electronic device including an inertial motion unit and a location data unit includes receiving, from the inertial motion unit of the wearable electronic device, user stride data and determining that location data is temporarily unavailable from the location data unit. The method also includes computing travel speed using information related to the user stride data and thereafter, determining that the location data is available from the location data unit. The method further includes computing an updated travel speed using information related to the location data and providing the user with the updated travel speed.

A method for determining a measurement signal based on a sensor output electrical signal. The electrical signal based on the measured quantity conversion of the electrical signal into a measurement signal. Determining the measurement signal for least two pairs of values by converting the electrical signal into a measurement signal for at least two predetermined electrical signal values, each pair of values including the electrical signal and measurement signal. A mathematical function allowing a measurement signal to be obtained based on the electrical signal is determined based on the pairs of values. The measurement signal being substantially equal to the measurement signal obtained by applying the sensor conversion to the same sensor electrical signal. At least two measurement signals are determined without sensor conversion. Acquisition of the two measurement signals separated by a time shorter than the time to convert an electrical signal into a measurement signal by sensor conversion.

A method and system for providing a self-test configuration in a device is disclosed. The method and system comprise providing a self-test mechanism in a kernel space of a memory and enabling a hook in a user space of the memory, wherein the hook is in communication with the self-test mechanism. The method and system also include running the self-test driver and utilizing the results.

A method and system for providing a self-test configuration in a device is disclosed. The method and system comprise providing a self-test mechanism in a kernel space of a memory and enabling a hook in a user space of the memory, wherein the hook is in communication with the self-test mechanism. The method and system also include running the self-test driver and utilizing the results.

An orientationally flexible bump sensor is disclosed. The system includes at least one bump sensor mounted to a vehicle, the at least one bump sensor comprising at least two axes of measurement. A computer processor is configured to evaluate the at least two axes of measurement to determine which axis of the at least two axes of measurement has a highest magnitude vector and determine a gain value to cause the highest magnitude vector to be approximately 1g. The computer processor will assign the gain value to the axis with the highest magnitude vector, such that the gain value is applied to each measurement generated by the axis with the highest magnitude vector.

A method including receiving, in a computing device, periodic measurements of accelerations from a plurality of sensor modules. The computing device determines whether each respective sensor module of the sensor modules is attached to a respective part of a user from the periodic measurements of accelerations from the plurality of sensor modules as received. In response to the determination that each respective sensor module of the sensor modules is attached to the respective part of the user, the method includes initiating, by the computing device, a calibration operation to calibrate orientation measurements of the sensor modules relative to a common reference system defined based on an orientation of the user.

A method including receiving, in a computing device, periodic measurements of accelerations from a plurality of sensor modules. The computing device determines whether each respective sensor module of the sensor modules is attached to a respective part of a user from the periodic measurements of accelerations from the plurality of sensor modules as received. In response to the determination that each respective sensor module of the sensor modules is attached to the respective part of the user, the method includes initiating, by the computing device, a calibration operation to calibrate orientation measurements of the sensor modules relative to a common reference system defined based on an orientation of the user.

An inertial sensor based surgical navigation system for knee replacement surgery is disclosed. Inertial sensors composed of six-degree-of-freedom inertial chips, whose measurements are processed through a series of integration, quaternion, and kalman filter algorithms, are used to track the position and orientation of bones and surgical instruments. The system registers anatomically significant geometry, calculates joint centers and the mechanical axis of the knee, develops a visualization of the lower extremity that moves in real time, assists in the intra-operative planning of surgical cuts, determines the optimal cutting planes for cut guides and the optimal prosthesis position and orientation, and finally navigates the cut guides and the prosthesis to their optimal positions and orientations using a graphical user interface.

An inertial sensor based surgical navigation system for knee replacement surgery is disclosed. Inertial sensors composed of six-degree-of-freedom inertial chips, whose measurements are processed through a series of integration, quaternion, and kalman filter algorithms, are used to track the position and orientation of bones and surgical instruments. The system registers anatomically significant geometry, calculates joint centers and the mechanical axis of the knee, develops a visualization of the lower extremity that moves in real time, assists in the intra-operative planning of surgical cuts, determines the optimal cutting planes for cut guides and the optimal prosthesis position and orientation, and finally navigates the cut guides and the prosthesis to their optimal positions and orientations using a graphical user interface.