Apparatus for Measuring Activity

Abstract

An apparatus for measuring activity of a test subject includes a buckle configured to engage with a belt strap to form a belt that is securable around a body portion of the test subject, and an activity measuring device secured to the buckle so as to facilitate recording activities of a test subject, the activity measuring device including at least one acceleration sensor configured to detect acceleration in all three spatial directions at right angles to each other.

1 . An apparatus for measuring activity of a test subject comprising:
 a buckle configured to engage with a belt strap to form a belt that is securable around a body portion of the test subject; and   an activity measuring device secured to the buckle so as to facilitate recording activities of a test subject, the activity measuring device including at least one acceleration sensor configured to detect acceleration in all three spatial directions at right angles to each other.   
     
     
         2 . The apparatus of  claim 1 , wherein the activity measuring device is secured to the belt buckle such that the activity measuring device is attached close to the center of gravity of the test subject's body. 
     
     
         3 . The apparatus of  claim 1 , wherein the activity measuring device telemeters the recorded measurement data via a radio link to a central server. 
     
     
         4 . The apparatus of  claim 3 , wherein the activity measuring device is configured to be connected electrically to a mobile telephone that is securable to the belt so as to facilitate data transmission between the activity measuring device and the mobile telephone. 
     
     
         5 . The apparatus of  claim 4 , wherein the activity measuring device includes an electrical cable that is configured to be electrically connected to a device interface of the mobile telephone. 
     
     
         6 . The apparatus of  claim 4 , wherein the measurement data recorded by the activity measuring device is transmitted to the mobile telephone via a device interface of the mobile telephone, and the measurement data is sent from the mobile telephone to the central server via the radio link. 
     
     
         7 . The apparatus of  claim 1 , wherein the at least one acceleration sensor of the activity measuring device comprises a unidimensionally operating acceleration sensor that records acceleration forces acting along a vertical spatial direction, and a bidimensionally operating acceleration sensor that records acceleration forces acting at right angles to the vertical spatial direction. 
     
     
         8 . The apparatus of  claim 5 , wherein a section of the belt adjoining the belt buckle on a side including the electrical cable side includes a Velcro fastener to receive the electrical cable. 
     
     
         9 . The apparatus of  claim 1 , wherein the activity measuring device includes a microprocessor configured to control the recording of measurement data and data transmission. 
     
     
         10 . The apparatus of  claim 1 , wherein the activity measuring device records and transmits measurement data with a sampling frequency in an order of magnitude of 100 Hz. 
     
     
         11 . The apparatus of  claim 1 , wherein the activity measuring device is configured to be secured to at least one of a front surface of the belt buckle, a back surface of the belt buckle, a side surface of the belt buckle, a top surface of the belt buckle and a bottom surface of the belt buckle. 
     
     
         12 . The apparatus of  claim 1 , wherein the activity measuring device is removably secured to the buckle. 
     
     
         13 . The apparatus of  claim 1 , wherein the activity measuring device is secured within the belt buckle. 
     
     
         14 . The apparatus according to  claim 1 , wherein the apparatus is configured to determine a current state of motion based upon continuous measurements of the body accelerations of the test subject, wherein a distinction is made between static and dynamic states of motion. 
     
     
         15 . The apparatus according to  claim 14 , wherein the apparatus is configured to make a distinction between sitting, standing and lying for static states of motion of the test subject, and between walking and jogging for dynamic states of motion of the test subject. 
     
     
         16 . The apparatus according to  claim 14 , wherein, in order to distinguish between static and dynamic states of motion, a maximum and a minimum in a series of consecutively measured acceleration values determined in the direction of one spatial axis are calculated and the difference between the maximum and the minimum is compared with a threshold value. 
     
     
         17 . The apparatus according to  claim 14 , wherein a movement of the test subject is detected when the inequality max−min>δ is fulfilled in at least one spatial axis direction, where max and min are respectively maximum and minimum values calculated from a series of consecutively measured acceleration values determined in the at least one spatial axis direction, and δ is a threshold value. 
     
     
         18 . The apparatus of  claim 1 , wherein the apparatus is configured to distinguish between states of motion of walking and jogging associated with the test subject by determining a mean difference from a mean of measured values in a series of measurements for each spatial axis direction, and by further comparing the mean difference determined for each spatial axis direction with a corresponding threshold value assigned to each spatial axis direction. 
     
     
         19 . The apparatus of  claim 1 , wherein the apparatus is configured to distinguish between states of motion of lying, standing and sitting associated with the test subject for each spatial axis direction by determining a mean for each spatial axis direction from a corresponding series of measurements determined for each spatial axis direction, and by further comparing each mean with a corresponding assigned threshold value for each spatial direction. 
     
     
         20 . A system comprising the apparatus of  claim 1  and a mobile telephone. 
     
     
         21 . An activity measuring device for recording the activity of a test subject, the activity measuring device including at least one acceleration sensor configured to continuously measure, in three spatial directions that are at right angles to each other, body accelerations underlying the momentary physical activity of the test subject, wherein the activity measuring device is configured to determine a current state of motion based upon the continuous measurements of the body accelerations of the test subject, and the activity measuring device is further configured to distinguish between states of motion of walking and jogging associated with the test subject by determining a mean difference from a mean of measured values in a series of measurements for each spatial axis direction, and by further comparing the mean difference determined for each spatial axis direction with a corresponding threshold value assigned to each spatial axis direction. 
     
     
         22 . An activity measuring device for recording the activity of a test subject, the activity measuring device including at least one acceleration sensor configured to continuously measure, in three spatial directions that are at right angles to each other, body accelerations underlying the momentary physical activity of the test subject, wherein the activity measuring device is configured to determine a current state of motion based upon the continuous measurements of the body accelerations of the test subject, and the activity measuring device is further configured to distinguish between states of motion of lying, standing and sitting associated with the test subject for each spatial axis direction by determining a mean for each spatial axis direction from a corresponding series of measurements determined for each spatial axis direction, and by further comparing each mean with a corresponding assigned threshold value for each spatial direction.