Journal Article

A Novel Unsupervised Adaptive Learning Method for Long-Term Electromyography (EMG) Pattern Recognition

Qi Huang, Hong Liu, Huajie Zhang, Dapeng Yang, Li Jiang, Kiyoshi Kotani

2017

Overview

Performance degradation will be caused by a variety of interfering factors for pattern recognition-based myoelectric control methods in the long term. This paper proposes an adaptive learning method with low computational cost to mitigate the effect in unsupervised adaptive learning scenarios. We presents a particle adaptive classifier (PAC), by constructing a particle adaptive learning strategy and universal incremental least square support vector classifier (LS-SVC). We compared PAC performance with incremental support vector classifier (ISVC) and non-adapting SVC (NSVC) in a long-term pattern recognition task in both unsupervised and supervised adaptive learning scenarios. Retraining time cost and recognition accuracy were compared by validating the classification performance on both simulated and realistic long-term EMG data. The classification results of realistic long-term EMG data showed that the PAC significantly decreased the performance degradation in unsupervised adaptive learning scenarios compared with NSVC (9.03% ± 2.23%, p < 0.05) and ISVC (13.38% ± 2.62%, p = 0.001), and reduced the retraining time cost compared with ISVC (2 ms per updating cycle vs. 50 ms per updating cycle).

• Publisher: MDPI AG,MDPI
• Subject: Adaptive learning / Algorithms / Capital goods / Chemical technology / concept drift / Electromyography / long-term EMG pattern recognition / long-term EMG pattern recognition; adaptive learning; concept drift; particle adaption; support vector classifier / Machine Learning / particle adaption / Pattern recognition / Pattern Recognition, Automated / support vector classifier / Teaching methods / TP1-1185