Method and system for personal dead-reckoning drift compensation using gait characteristics

A system for compensating for drift in dead reckoning calculations for a user undergoing locomotion comprising:

• an inertial measurement unit (IMU) attached to the user;
• one or more sensors attached to the user;
• one or more processors;
• and
• modules of program code;
• wherein the modules of program code are configured, when executed by the processors to:
• define a first point at which the IMU is located;
• detect a phase of a gait of the user using the one or more sensors;
• define bounds for displacement of the IMU during said phase of the gait;
• obtain raw positional data from the IMU for a second point, to which the IMU is displaced by the locomotion of the user;
• determine whether said raw positional data lies within or outside of said bounds;
• if the raw positional data lies within the bounds, output the raw positional data as dead reckoned data for the second point;
• and
• if the raw positional data lies outside the bounds, compensate the raw positional data to result in compensated positional data that is within the bounds and output the compensated positional data as the dead reckoned data for the second point.

A computer readable medium comprising computer readable instructions, which, when executed by a processor, cause a system for compensating for drift in dead reckoning calculations for a user undergoing locomotion to:

• define a first point at which an inertial measurement unit (IMU) attached to a user is located;
• detect a phase of a gait of the user using one or more sensors that are attached to the user;
• define bounds for displacement of the IMU during said phase of the gait;
• obtain raw positional data from the IMU for a second point, to which the IMU is displaced by the locomotion of the user;
• determine whether said raw positional data lies within or outside of said bounds;
• if the raw positional data lies within the bounds, output the raw positional data as dead reckoned data for the second point;
• and
• if the raw positional data lies outside the bounds, compensate the raw positional data to result in compensated positional data that is within the bounds and output the compensated positional data as the dead reckoned data for the second point.