Upper Limb Muscle Strength Analysis For Movement Sequence Based on Maximum Voluntary Contraction Using EMG Signal

摘要

This paper presents the studies of analysis upper limb muscle strength during arm movement sequence for the purpose of upper limb rehabilitation after stroke. The recovery of the arm could be optimized if the rehabilitation therapy is in a right manner. Upper limb weakness after stroke is prevalent in rehabilitation, many factors that can deficit muscle strength there are neural, muscle structure and function change after stroke. Maximum Voluntary Contraction (MVC) is one of the methods to rescale per cent of a reference value unique and standardized for all subjects within a study, This allows to compare of electromyography signal findings between subjects directly and quantitative. The objective of this research to evaluate muscle strength fatigue for movement sequence rehabilitation after stroke. 5 healthy subjects including both male and female performed a functional movement and a fundamental movement. Electromyography device is used to measure and record movement arm involving deltoid, biceps and flexor carpum ulnaris (FCU). A signal processing technique is employed to analyze the upper limb movement signals and several movement features are determined, which is the root mean square (RMS) and mean absolute value (MAV). By referring to the information from the previous research frequency domain (FD) feature is usually used in the assessing muscle strength fatigue. The experiment results show that for the highest value of movement sequence contraction based of MVC for deltoid muscle is 96% (RMS) and 93% (MAV) by subject #1 and the highest value for biceps is 90% (RMS) and 93% (MAV) by subject #4. The highest value for FCU muscle is 78% (RMS) and 82% (MAV) by subject #5. And the highest power contraction for movement sequence based MVC is deltoid muscle with 88% (RMS) and 90% (MAV) and the lowest power contraction for movement sequence based MVC is 49% (RMS) and 58% (MAV). The benefit of maximum voluntary contraction (MVC) is important to rescaling to a per cent of a reference value unique and standardized for all subjects. Maximum voluntary contraction is important because it can be used to rescaling value of EMG signal, to be a reference value for analysis and investigation of muscle contraction and can be used to classification subject or patient based muscle contraction. Differences in muscle strength each human are caused by several factors including age, muscle sizes, muscle conditions and body conditions.