Methods and systems for non-contact magnetostrictive sensor runout compensation

A computer-implemented method for reducing runout and vibration noise from a stress sensing system, said method comprising:

• receiving at least one signal from at least one stress sensor, the at least one signal indicative of stress in a conductive target material;
• receiving rotation signal characterizing a detected rotation of the conductive target material;
• selecting a zero stress portion of the at least one signal corresponding to a zero stress condition of the conductive target material;
• resampling the zero stress portion to an angle domain corresponding to the conductive target material;
• extracting a sample portion of the zero stress portion to define a time-synchronous runout pattern of the at least one signal, the sample portion including a first portion of the zero stress portion corresponding to a single rotation of the conductive target material, wherein the sample portion of the zero stress portion comprises a first portion and a second portion of the zero stress portion, the first and second portions of the zero stress portion corresponding to a first and a second rotation of the conductive target material, respectively;
• determining a runout portion of the at least one signal that corresponds to runout of the conductive target material based on the rotation signal;
• determining a runout pattern waveform from the runout portion of the at least one signal, the determining includes averaging the first and second portions of the zero stress portion;
• generating a compensated torque signal waveform by subtracting the runout pattern waveform from the at least one signal;
• and
• providing the compensated torque signal waveform.

A non-transitory computer readable medium that includes computer executable instructions for reducing runout and vibration noise from a stress sensing system, the stress sensing system including a computing device, wherein when executed by the computing device, the computer executable instructions cause the computing device to:

• receive at least one signal from at least one stress sensor, the at least one signal indicative of stress in a conductive target material;
• select a zero stress portion of the at least one signal corresponding to a zero stress condition of the conductive target material;
• resample the zero stress portion to an angle domain corresponding to the conductive target material;
• extract a sample portion of the zero stress portion to define a time-synchronous runout pattern of the at least one signal, the sample portion including a first portion of the zero stress portion corresponding to a single rotation of the conductive target material, wherein the sample portion of the zero stress portion comprises a first portion and a second portion of the zero stress portion, the first and second portions of the zero stress portion corresponding to a first and a second rotation of the conductive target material, respectively;
• receive rotation signal characterizing a detected rotation of the conductive target material;
• determine a runout portion of the at least one signal that corresponds to runout of the conductive target material based on the rotation signal;
• determine a runout pattern waveform from the runout portion of the at least one signal, the determination includes averaging the first and second portions of the zero stress portion;
• generate a compensated torque signal waveform by subtracting the runout pattern waveform from the at least one signal;
• and
• provide the compensated torque signal waveform.

A stress sensing system for measuring stress in a conductive target material, said stress sensing system comprising:

• at least one sensor positioned proximate to the conductive target material, said at least one sensor configured to measure stress in the conductive target material and to transmit at least one signal indicative of the measured stress;
• and
• at least one controller coupled in communication with said at least one sensor, said at least one controller configured to:
• receive the at least one signal from said at least one sensor;
• select a zero stress portion of the at least one signal corresponding to a zero stress condition of the conductive target material;
• resample the zero stress portion to an angle domain corresponding to the conductive target material;
• extract a sample portion of the zero stress portion to define a time-synchronous runout pattern of the at least one signal, the sample portion including a first portion of the zero stress portion corresponding to a single rotation of the conductive target material, wherein the sample portion of the zero stress portion comprises a first portion and a second portion of the zero stress portion, the first and second portions of the zero stress portion corresponding to a first and a second rotation of the conductive target material, respectively;
• receive a second signal indicative of a rotation of the conductive target material;
• determine a runout portion of the at least one signal corresponding to runout of the conductive target material based on the second signal;
• determine a runout pattern waveform from the runout portion, the determination includes averaging the first and second portions of the zero stress portion;
• generate a compensated torque signal waveform by subtracting the runout pattern waveform from the at least one signal;
• and
• provide the compensated torque signal waveform.