Movement analysis using IMU sensor on the chest, extract gait parameters and estimate orientation.
Data acquisition
• Off-the-shelf Movesense 6-axis IMU sensor
• Fixed on the chest with elastic strips
Experimental design
• Walking at normal speed in a corridor (Back and forth)
• Accelerometer and gyroscope data are recorded and synchronize
Algorithm design and parameter extraction
Estimate orientation
• Accelerometer measures acc. along x,y,z axis (m/s^2) : noisy
• Gyroscope measures angular speed around x,y,z axis (deg/s) : drift
• Sensor fusion (Kalman filter)
Gait parameters extraction
•Step count
•Cadence
•Average step time
•Vertical oscillation
•3D trajectory of the sensor
• Step count: 28 steps during the period.
• Cadence: 84.22 steps per minute
• Average step time: 0.71 seconds
Filtering the acceleration data:
- Low-pass filter to remove high frequency noise
2. Finding peaks: Identify the local maxima that correspond to the foot strikes
• Vertical oscillation: how much you move up and down (0.85 m/s²)
Standard deviation of the filtered vertical acceleration during the steps
• 3D trajectory of the sensor:
Double integration of the accelerometer data
Results
Results of the orientation estimation
With proposed algorithm V.S. Integrate algorithm
Validity result of our algorithm and reference angle from an Optical Motion Capture
Demo of Orientation Estimation
Future work
• Com calculation
• Extract other parameters:
stride time, stance duration, swing duration, single-support duration, double-support duration
