Patent ID: 11906381
Assignee: FUDAN UNIVERSITY
Field: Measurement (Instruments)
Classification: CPC G  Y | IPC G

Claim 5:
6. A torque measurement method using the magnetically induced torque measure device as claimed in claim 1, comprising:
a first step: calculate a worst gravity moment τworst=m·Lmaximum·g of the sample according to a mass m and a maximum linear dimension Lmaximum of the sample, select a target detachable torsion spring set according to the worst gravity moment and securing the target detachable torsion spring set on the measurement device;
a second step: rotate the adjustment knob of the lifting platform to adjust the height of the loading tray to be consistent with a known magnet center height, and simultaneously adjust the lengths of the four adjustment belts to make the four adjustment belts tight;
a third step: fix the sample on the loading tray by a thread, then place the measurement device on the bed of the MR system, and based on a built-in cross-positioning of the magnetic resonance equipment, move the bed to position the center of the sample to a magnet center;
a fourth step: a tester enters a testing chamber, and turns the knob to adjust the angle of the loading tray and thereby make the axis of the sample coincide with a Z-axis of a magnet coil;
a fifth step: rotate the knob with 90° to make the loading tray be rotated with 10° and continue rotating until the loading tray is rotated with 360°, and recording a change of the angle of the loading tray before and after each time of the loading tray being rotated through the MRI-compatible camera;
a sixth step: calculate the deflection angle of the sample as Δθ=θafter−θbefore according to recorded angles θbefore, θafter of the loading tray before and after each time of the loading tray being rotated, and calculate magnetically induced torque of the sample according to formula τ=k·Δθ, where τ represents the magnetically induced torque, and k represents an elastic coefficient of torsion spring; and
a seventh step: recheck the magnetically induced torque calculated in the sixth step; when relative errors of all calculated values are within a specified range, continue using the selected target detachable torsion spring set, change the fixed direction of the sample to make another axis of the sample coincide with the Z axis at an initial measurement position, and repeat the fourth through sixth steps; when the relative error of any one of the all calculated values is not within the specified range, replace with a larger or a smaller detachable torsion spring, do not change the fixed direction of the sample, and repeat the fourth through sixth steps until relative errors of all calculated values meet a relative error requirement.