A Novel Framework Based on Position Verification for Robust Myoelectric Control Against Sensor Shift

This study presented a novel framework to improve the robustness of pattern recognition-based myoelectric control algorithms against sensor shift, which was one of the obstacles for its practical applications outside controlled laboratory conditions. Different from the previous proposed methods, which mostly focused on improving the classification performance in the shift condition, this framework provided the functionality of verifying if the sensor position was shifted. If so, the user was enabled to adjust the sensor position before it affecting the following control. We demonstrated that one verification attempt could be completed in a short time (<; 2 s) with a high accuracy (equal error rate, or EER<; 5%). The control performance was theoretically proved to be improved after position verification. The simulated results of the experimental data from six sensors around the arm showed that with improved discrete Fourier transform (iDFT) feature, in most scenarios, smaller than five verification attempts (<; 10 s) were needed to correct the sensor position from 1-cm shift perpendicular to muscle fibers. The performance after correction was comparable to that of a traditional method including additional training data from the expected shift positions. The proposed framework dealt with the sensor shift problem from the perspective of efficient position correction, potentially expanding the application of myoelectric control, especially with armband, in industry.