Comparator apparatus and system for activity monitors

• US 5,762,072 A
• Filed: 05/25/1995
• Issued: 06/09/1998
• Est. Priority Date: 05/25/1995
• Status: Expired due to Term

• Current Assignee: Precision Control Design Incorporated
• Original Assignee: Precision Control Design Incorporated
• Inventors: Conlan, Robert W., Godwin, Markham C.
• Primary Examiner(s): Buiz, Michael
• Assistant Examiner(s): RASCHE, PATRICK WILLIAM
• Application Number:
  US08/450,345
• Time in Patent Office: 1,111 Days
• Field of Search: 128/782, 128/670, 128/671, 128/690, 128/721, 128/774, 128/722, 128/687, 128/713, 128/714, 607/19
• US Class Current: 600/595
• CPC Class Codes: A61B 5/02 Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
• CPC Class Codes: A61B 5/1118 Determining activity level
• CPC Class Codes: A61B 5/681 Wristwatch-type devices
• CPC Class Codes: A61B 5/6824 Arm or wrist

Abstract

A comparator for comparing the operation of activity monitors of the type having internal sensors responsive to excitation forces in order to record the activity of a wearer, includes a housing having a test platform and a monitor-receiving test fixture for holding an activity monitor motionless during testing. The comparator further includes an electromagnet for applying an excitation force to the monitor, by converting a prerecorded digital signal, or waveform, into analog voltage signals which are applied to the electromagnet for testing the monitor. The monitor may be subjected to a variety of test patterns of activity.

Claims

1. An activity monitor interface apparatus for providing an interface for data communication between an activity monitor having an internal sensor which determines activity of a subject using said activity monitor and a computer, the apparatus being capable of testing operation of the internal sensor of said activity monitor, said apparatus comprising:

a test platform;

test receptacle means for receiving an activity monitor and holding it substantially motionless upon the test platform in a testing position;

memory means for storing at least one predetermined test pattern of activity;

conversion means for converting the activity test pattern, upon retrieval from the memory means, into an excitation signal representative of said predetermined activity test pattern;

activity monitor exciting means which receives the excitation signal and applies an excitation force to an activity monitor held in said receptacle means in order to excite the activity monitor internal sensor in a manner which substantially replicates said predetermined activity test pattern; and

data transmission means for transmitting data generated by said activity monitor held in said receptacle means in response to said excitation force for comparison with said predetermined activity test pattern.

2. The activity monitor interface apparatus as defined in claim 1, wherein said memory means includes a read-only memory (ROM) and said conversion means includes a digital-to-analog connector (DAC).

3. The activity monitor interface apparatus as defined in claim 2, wherein said activity monitor exciting means includes an electromagnet which generates a magnetic field upon application of said excitation signal, the magnetic field inducing a response in said activity monitor internal sensor.

4. The activity monitor interface apparatus as defined in claim 1, wherein said data transmission means includes a transformer and opto-isolated RS-232 communication datalink.

5. The activity monitor interface apparatus as defined in claim 1, wherein said test platform includes a housing, said test receptacle means being disposed on a surface of the housing, and said activity monitor exciting means includes an electromagnet disposed within said housing proximate to and opposing said test receptacle means.

6. The activity monitor interface apparatus as defined in claim 1, wherein said test pattern of activity has a frequency of between 0.2 and 10 Hz.

7. The activity monitor interface apparatus as defined in claim 1, further including an RS-232 data port for transmitting said data generated by said activity monitor.

8. An activity monitor interface apparatus for providing an interface for data communication between an activity monitor and a computer for testing the activity monitor, the activity monitor having a sensor which determines activity of a subject using said monitor and which generates an output indicative of the activity of said subject, the interface apparatus comprising:

test receptacle means for receiving an activity monitor and holding it substantially motionless upon the test platform in a testing position;

activity monitor exciting means which receives a predetermined excitation signal and applies an excitation force in response to receipt of said predetermined excitation signal, the activity monitor exciting means applying said excitation force to an activity monitor held in said receptacle means in order to excite the activity monitor; and

data transmission means for transmitting data generated by said activity monitor held in said receptacle means in response to said excitation force for comparison with said predetermined excitation signal.

9. The activity monitor interface apparatus as defined in claim 8, further including memory means for storing in digital format at least one predetermined test pattern of activity and conversion means for converting the predetermined test pattern into said predetermined excitation signal.

10. The activity monitor interface apparatus as defined in claim 9, wherein said conversion means includes a digital-to-analog convertor (DAC) which converts said predetermined test pattern into said predetermined excitation signal.

11. The activity monitor interface apparatus as defined in claim 10, further including driving means for driving said activity monitor exciting means in response to said predetermined excitation signal, the driving means receiving said predetermined excitation signal from said conversion means in the form of a voltage output from said DAC.

12. The activity monitor interface apparatus as defined in claim 11, wherein said driving means includes a transistor and said activity monitor exciting means includes an electromagnet driven by said transistor, said transistor receiving a voltage output from said conversion means as said predetermined excitation signal and said driving means outputting said predetermined excitation signal as a current to said electromagnet to thereby generate said excitation force in the form of a magnetic field which replicates said predetermined test pattern of activity.

13. The activity monitor interface apparatus as defined in claim 9, wherein said memory means includes a ROM.

14. An apparatus for testing an activity monitor to determine at least one operational characteristic of the activity monitor, said activity monitor including an activity sensor which is responsive to an applied magnetic field, the apparatus comprising means for applying a magnetic field to said activity monitor sensor to test said activity monitor sensor and means for determining the responsiveness of said activity monitor sensor to the applied magnetic field, said magnetic field being variable in order to excite said activity monitor sensor in accordance with a variety of predetermined test patterns.

15. A system for assessing operation of an activity monitor, comprising:

means for storing a predetermined test pattern of activity in memory,

conversion means for converting the predetermined test pattern of activity to a voltage and outputting the voltage as an excitation signal which substantially replicates said predetermined test pattern of activity,

generating means for generating a current in synchronization with said voltage output from said conversion means and outputting said current,

a receptacle for receiving an activity monitor and holding it motionless during assessment of the operation of the activity monitor,

means for generating a magnetic field proximate to said receptacle in response to said current output by the current generating means in accordance with said predetermined test pattern of activity, which induces a response in said activity monitor when received within said receptacle, and

a computer for correlating said predetermined test pattern of activity to said activity monitor response and determining any differences therebetween.

16. The system as defined in claim 15, wherein said means for storing includes a read-only-memory.

17. The system as defined in claim 15, wherein said conversion means for converting includes a digital-to-analog converter.

18. The system as defined in claim 15, wherein said generating means for generating includes a transistor.

19. The system as defined in claim 15 further comprising response signal generating means for generating a response signal resulting from said response of said activity monitor and data transmission means for transmitting said response signal to said computer.

20. An activity monitor interface apparatus for interfacing between a processing unit and an activity monitor and for testing operation of the activity monitor, said activity monitor being one which is worn by a subject and detects and records occurrences of body movements of the subject, the interface apparatus comprising:

a receptacle unit which receives said activity monitor during testing of said activity monitor;

an excitation component that applies an excitation signal of interest to said activity monitor received in said receptacle during testing of said activity monitor to induce said activity monitor to generate a response signal in response to said excitation signal; and

,

a transmission path that provides an electrical communication path between said receptacle unit and a processing unit, the transmission path transmitting the response signal generated by said activity monitor to the processing unit for comparison with said excitation signal.