Automatic test parameters compensation of a real time fluid analysis sensing device

A system for sensing at least one component concentration in a fluid test sample, comprising a reading apparatus and a disposable sensing device, the disposable sensing device comprising:

• at least one sensor;
• sample retaining means for retaining the fluid sample out of contact with the sensor prior to sensing;
• a sample conduit connecting the sample retaining means with the sensor;
• and
• sample displacement means for automatically and forcibly displacing the sample through the sample conduit and into contact with the sensor to enable sensing;
• the reading apparatus comprising:
• receiving means for receiving the disposable sensing device;
• control means for controlling the automatic displacement of the fluid test sample by the sample displacement means of the disposable sensing device;
• first memory means to store output characteristics of the sensor;
• and
• automatic compensation means for maintaining close to a target value the mean fluid displacement by adjusting input parameters of the control means in response to the stored output characteristics following each measurement.

An automatic compensation method for maintaining close to a target value the mean fluid displacement samples in a succession of test measurements of a fluid sensing instrument which includes an actuation mechanism for the displacement of fluids along a predetermined fluid path during each test measurement and at least one sensor, the method comprising the steps of:

• (a) storing in memory means a parameter associated with the target value of test fluid volume required to pass over the sensor;
• (b) recording the time of arrival of the test fluids at the sensor by measuring an output characteristic of the sensor;
• (c) following the recorded time of arrival, for each test fluid sample comparing an output characteristic of the sensor to the stored parameter value;
• and
• (d) compensating in response to the comparison the motion of the fluid actuation mechanism to keep the mean test sample fluid volume close to the target value.