Pedometer in a low-power device
AssigneeGoogle Inc.
InventorsMichael R. Plasterer, Samuel P. Kho
Life of this patent
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Abstract
Methods and systems for determining a user's steps in portable device include deriving amplitudes from raw sensor data; comparing the amplitudes to an amplitude threshold, and counting a step when one of the amplitudes exceeds the amplitude threshold to obtain a step count; determining a current gait type based on the step count; dynamically adjusting the amplitude threshold in order to reduce effects of swinging movements and false steps; and applying a post filter to the step count based on time between steps and a minimum number of prior consecutive steps to derive a filtered step count that reduces false readings due to short bursts of rapid movement by the user.
Claims29
A method for determining a user's steps by a portable device carried by a user, the method comprising:
- measuring, by at least one sensor of the portable device, raw sensor data including one or more of position, motion, tilt, shock or vibration, the at least one sensor including at least one inertial sensor;
- deriving amplitudes from the raw sensor data received from the at least one sensor of the portable device, by at least one processor of the portable device, the at least one processor including a first processor comprising a microcontroller unit (MCU);
- comparing, by a given one of the at least one processor, the amplitudes to an amplitude threshold, and counting a step when one of the amplitudes exceeds the amplitude threshold to obtain a step count, wherein if the amplitude threshold is not exceeded for a given amplitude, a step is not counted;
- determining, by a given one of the at least one processor, a current gait type based on the step count and a pace of the user's steps;
- dynamically adjusting, by a given one of the at least one processor, the amplitude threshold based on the current gait type to reduce false amplitude peaks in order to filter out swinging movements and false steps;
- and
- applying a post filter to the step count, by a given one of the at least one processor, based on time between steps and a minimum number of prior consecutive steps to derive a filtered step count, the filtered step count being used by the given processor to identify false readings due to short bursts of rapid movement by the user.
A portable device configured to determine a user's steps, the portable device comprising:
- an inertial sensor configured to measure raw sensor data including one or more of position, motion, tilt, shock or vibration;
- a first processor coupled to the inertial sensor and configured to receive the raw sensor data from the inertial sensor;
- and
- a step count component executing on the first processor, wherein the step count component is configured to:
- derive amplitudes from the raw sensor data received from the inertial sensor;
- compare the amplitudes to an amplitude threshold, and counting a step when one of the amplitudes exceeds the amplitude threshold to obtain a step count, wherein if the amplitude threshold is not exceeded for a given amplitude, a step is not counted;
- determine a current gait type based on the step count and a pace of the user's steps;
- dynamically adjust the amplitude threshold based on the current gait type to reduce false amplitude peaks in order to filter out swinging movements and false steps;
- and
- apply a post filter to the step count based on time between steps and a minimum number of prior consecutive steps to derive a filtered step count, the filtered step count being used by the step count component to identify false readings due to short bursts of rapid movement by the user.
A computer readable storage device having executable program instructions for determining a user's steps, the program instructions, when executed by one or more processing devices of a portable client device including a microcontroller unit (MCU), causing the one or more processors to implement a method for determining a user's steps by the portable device, the method comprising:
- measuring raw sensor data including one or more of position, motion, tilt, shock or vibration, the at least one sensor including at least one inertial sensor;
- deriving amplitudes from the raw sensor data received from the at least one sensor of the portable device;
- comparing the amplitudes to an amplitude threshold, and counting a step when one of the amplitudes exceeds the amplitude threshold to obtain a step count, wherein if the amplitude threshold is not exceeded for a given amplitude, a step is not counted;
- determining a current gait type based on the step count and a pace of the user's steps;
- dynamically adjusting the amplitude threshold based on the current gait type to reduce false amplitude peaks in order to filter out swinging movements and false steps;
- and
- applying a post filter to the step count based on time between steps and a minimum number of prior consecutive steps to derive a filtered step count, the filtered step count being used to identify false readings due to short bursts of rapid movement by the user.
Dependencies are inferred from the claim text.