Gait activity monitor

  • US 5,485,402 A
  • Filed: 03/21/1994
  • Issued: 01/16/1996
  • Est. Priority Date: 03/21/1994
  • Status: Expired due to Term
  • ×
    • Pin
First Claim
Patent Images

1. A monitor for determining the step activity of a wearer comprising:

  • a housing having a communication surface, said communication surface being selected of a material and opacity to permit transmission of infrared radiation, said housing having a support surface that is shaped and contoured to mate with an ankle of the wearer, said housing including a strap, fixed to the exterior of said housing, for releasably mounting the monitor to the ankle of the wearer;

    an electronic accelerometer for providing an acceleration signal indicative of the acceleration of said housing;

    a step determination unit coupled to receive the acceleration signal, said step determination unit including a memory device for recording a minimum acceleration data unit, a maximum acceleration data unit, and a minimum time unit, said step determination unit comparing the stored minimum acceleration data unit and the minimum time unit with the received acceleration signal for determining when the wearer of the monitor has taken a step and said step determination unit providing a step signal to indicate that the user has taken a step when the received acceleration signal is both greater than the stored minimum acceleration data unit, and less than the maximum acceleration data unit for the minimum time unit;

    processor memory for storing data relating to the step activity of the wearer and for storing step activity data including a time interval data unit indicating the length of a measurement interval and a step rate data unit indicating the amount of time that the step signal will be ignored after a step is counted;

    a data processor for determining the step activity of the wearer, said data processor being coupled to said step determination unit and said processor memory, said data processor including a first timer for counting consecutive measurement time intervals wherein each measurement time interval is equal to the time specified by the time interval data unit stored in said processor memory, said data processor including a second timer for counting a step rate time interval wherein each step rate time interval is equal to the time specified by the step rate data unit stored in said processor memory, said data processor being responsive to said first timer and the step signal for storing a plurality of step count data units in said processor memory wherein each step count data unit represents the number of steps made during the measurement time interval, said data processor being responsive to said second timer to count only one step during each step rate time interval;

    a monitor interface, including a monitor transceiver, for transmitting and receiving infrared radiation, said monitor interface being constructed for converting received infrared radiation to electronic signals and for converting electronic signals to infrared radiation, said monitor interface being coupled to exchange electronic signals with said data processor, said electronic accelerometer, said step determination unit, said processor memory, and said data processor each being mounted in said housing with said transceiver being mounted proximate to said communication surface;

    an interface module for receiving and transmitting infrared radiation to and from said monitor interface, including an interface transceiver, said interface module being constructed to convert received infrared radiation to electronic signals and to convert electronic signals to infrared radiation; and

    a system processor coupled to exchange electronic signals with said interface module, said system processor including a user interface and being responsive to user input for establishing communication with said data processor by way of said interface module and said monitor interface, said system processor being constructed to respond to user input to provide the time interval data unit and the step rate data unit to said data processor for storage in said processor memory, said system processor being further responsive to user input for providing the minimum acceleration data unit, and the minimum time unit to said data processor for storage in said memory device of said step determination unit, said data processor being responsive to control signals received from said system processor to provide the plurality of step count data units to said system processor.

View all claims
    ×
    ×

    Thank you for your feedback

    ×
    ×