FTA-Sensor: Combination of Force/Torque and Acceleration - Robotized Transcranial Magnetic Stimulation - page 111

Fig. 6.11 Stability of the
calibration of IMU to FT
coordinate frame as a
Boxplot. The errors for each
used FTA sensor and the
overall error are shown
6.2.1.3 Stability of the Calibration
To analyze the dependency of the calibration method to noise in the recordings, we
have compared the calibration results for the single FTA sensors among one
another.
In total, we have evaluated the stability of the calibration on almost 7 ; 000
combinations of calibration results. Figure 6.11 shows the results as a Boxplot.
The median deviation is 0.89 . For the sensors 1 and 3, the median error was even
below 0.7 .
6.2.2 Gravity Compensation
We have collected roughly 20,000 data points to evaluate the accuracy of the
gravity compensation based on accelerations. The error is estimated as the absolute
difference of the compensated recordings to zero.