摘要 |
A filter processes acceleration magnitude signals from an accelerometer device to output spectral content related to walking and running. A device containing the accelerometer determines steps by qualitatively analyzing the processed acceleration signals to determine whether increased acceleration magnitude results from a step impact from running or walking activity. The device may analyze the acceleration signals to determine crossings of an axis at zero magnitude, which crossings typically correspond to a person's foot impacting the ground, and may analyze the period, between the zero crossings. The step count can indicate whether the device, in a height determination mode, is moving in a vehicle; if analysis of accelerometer signals indicates no stepping or running, but another circuit of the device indicates rapid movement, the device assumes it is moving in a vehicle, and resets a height above ground value to zero upon determining resumption of walking or running activity. |