Calculation device, calculation method, and program recording medium
AssigneeNEC Corporation
InventorsChenhui Huang, Kenichiro Fukushi, Zhenwei Wang
Life of this patent
Estimating the term…
Abstract
In order to calculate, with a high degree of accuracy, step lengths for both feet on the basis of a physical quantity relating to the movement of one foot, this calculation device includes: a detection unit that generates a walking waveform using sensor data and detects a walking event from the generated walking waveform, the sensor data being based on a physical quantity that is measured by a sensor positioned on one foot of a walker and relates to the movement of the foot; and a step length calculation unit that calculates the step lengths for both left and right feet on the basis of the timing of the detected walking event.
Claims7
A calculation device comprising:
- one or more memories storing instructions;
- and
- one or more processors configured to execute the instructions to:
- receive sensor data via wireless communication from a data acquisition device installed in footwear of a pedestrian, the data acquisition device including an acceleration sensor and an angular velocity sensor;
- convert the received sensor data from a local coordinate system set in the data acquisition device to a world coordinate system set with respect to a ground;
- generate time-series data associated with walking of the pedestrian in the world coordinate system using the converted sensor data;
- calculate a spatial angle including a plantar angle using at least one of spatial acceleration and spatial angular velocity in the time-series data, and generate time-series data of the plantar angle;
- detect, in a gait waveform of the plantar angle for two gait cycles, a time at which the gait waveform becomes minimum and a time at which the gait waveform becomes maximum;
- calculate a midpoint time between the detected minimum time and the detected maximum time as a start point of one gait cycle, and calculate a next midpoint time as an end point of the one gait cycle;
- cut out, from the time-series data, a gait waveform for the one gait cycle from the start point to the end point;
- generate a gait waveform using the sensor data based on a physical quantity related to movement of a foot of the pedestrian measured by the data acquisition device;
- detect a gait event from the generated gait waveform;
- calculate step lengths of left and right feet based on a timing of the detected gait event;
- calculate asymmetry of the step lengths of the left and right feet;
- calculate a value obtained by dividing the difference between the step lengths of the left and right feet by a sum of the step lengths of the left and right feet as the asymmetry of the step lengths of the left and right feet;
- estimate a physical condition of the pedestrian based on the calculated asymmetry of the step lengths of the left and right feet using a machine learning model;
- and
- transmit information relating to the estimated physical condition, to encourage the pedestrian to make a decision, to a display device via communication network for displaying the information on a screen of the display device.
A calculation method for causing a computer to execute:
- receiving sensor data via wireless communication from a data acquisition device installed in footwear of a pedestrian, the data acquisition device including an acceleration sensor and an angular velocity sensor;
- converting the received sensor data from a local coordinate system set in the data acquisition device to a world coordinate system set with respect to a ground;
- generating time-series data associated with walking of the pedestrian in the world coordinate system using the converted sensor data;
- calculating a spatial angle including a plantar angle using at least one of spatial acceleration and spatial angular velocity in the time-series data, and generate time-series data of the plantar angle;
- detecting, in a gait waveform of the plantar angle for two gait cycles, a time at which the gait waveform becomes minimum and a time at which the gait waveform becomes maximum;
- calculating a midpoint time between the detected minimum time and the detected maximum time as a start point of one gait cycle, and calculate a next midpoint time as an end point of the one gait cycle;
- cutting out, from the time-series data, a gait waveform for the one gait cycle from the start point to the end point;
- generating a gait waveform using the sensor data based on a physical quantity related to movement of a foot of the pedestrian measured by the data acquisition device;
- detecting a gait event from the generated gait waveform;
- calculating step lengths of left and right feet based on a timing of the detected gait event;
- calculating asymmetry of the step lengths of the left and right feet;
- calculating a value obtained by dividing the difference between the step lengths of the left and right feet by a sum of the step lengths of the left and right feet as the asymmetry of the step lengths of the left and right feet;
- estimating a physical condition of the pedestrian based on the calculated asymmetry of the step lengths of the left and right feet using a machine learning model;
- and
- transmitting information relating to the estimated physical condition, to encourage the pedestrian to make a decision, to a display device via communication network for displaying the information on a screen of the display device.
A non-transitory program recording medium recorded with a program for causing a computer to execute:
- processing of sensor data received via wireless communication from a data acquisition device installed in footwear of a pedestrian, the data acquisition device including an acceleration sensor and an angular velocity sensor;
- processing of converting the received sensor data from a local coordinate system set in the data acquisition device to a world coordinate system set with respect to a ground;
- processing of generating time-series data associated with walking of the pedestrian in the world coordinate system using the converted sensor data;
- processing of calculating a spatial angle including a plantar angle using at least one of spatial acceleration and spatial angular velocity in the time-series data, and generate time-series data of the plantar angle;
- processing of detecting, in a gait waveform of the plantar angle for two gait cycles, a time at which the gait waveform becomes minimum and a time at which the gait waveform becomes maximum;
- processing of calculating a midpoint time between the detected minimum time and the detected maximum time as a start point of one gait cycle, and calculate a next midpoint time as an end point of the one gait cycle;
- processing of cutting out, from the time-series data, a gait waveform for the one gait cycle from the start point to the end point;
- processing of generating a gait waveform using the sensor data based on a physical quantity related to movement of a foot of the pedestrian measured by the data acquisition device;
- processing of detecting a gait event from the generated gait waveform;
- and
- processing of calculating step lengths of left and right feet based on a timing of the detected gait event;
- and
- processing of calculating asymmetry of the step lengths of the left and right feet;
- processing of calculating a value obtained by dividing the difference between the step lengths of the left and right feet by a sum of the step lengths of the left and right feet as the asymmetry of the step lengths of the left and right feet;
- processing of estimating a physical condition of the pedestrian based on the calculated asymmetry of the step lengths of the left and right feet using a machine learning model;
- and
- processing of transmitting information relating to the estimated physical condition, to encourage the pedestrian to make a decision, to a display device via communication network for displaying the information on a screen of the display device.
Dependencies are inferred from the claim text.