Apparatus and methods for determining force applied to the tip of a probe

An apparatus comprising an elongate probe, said elongate probe being an electrical impedance spectroscopy probe for investigating the electrical conductivity or bioimpedance of cervical tissue, the apparatus capable of determining a force Ftip applied to the tip of said elongate probe, the apparatus comprising:

• a handle;
• said elongate probe comprising said probe tip attached to said handle, wherein the probe tip comprises an EEPROM within the probe tip and wherein a mass of the probe tip is stored on the EEPROM;
• a load cell located in said handle and capable of measuring a force Floadcell applied axially to said probe tip along a longitudinal axis thereof when said probe tip is in contact with said human or animal cervical tissue, wherein said load cell comprises four strain gauges in a bridge configuration, wherein the bridge configuration is excited by bursts of square wave pulses at a frequency of 1 kHz;
• an accelerometer located in the handle for measuring a gravity vector Aaxial, the accelerometer in fixed relationship with the probe tip and the load cell;
• and
• a microcontroller for compensating for the mass of the probe tip using said measured force and gravity vector to produce a calibrated measurement of said force Ftip applied to said probe tip, the microcontroller generating a displayable output for indicating to a user the calibrated measurement of said force Ftip;
• wherein said probe tip is an interchangeable probe tip removably attached to said handle.