A new simple dynamic muscle fatigue model and its validation

Abstract

Musculoskeletal disorder (MSD) is one of the major health problems in physical work especially in manual handling jobs. In several literatures, muscle fatigue is considered to be closely related to MSD, especially for muscle related disorders. In addition to many existing analysis techniques for muscle fatigue assessment and MSD risk analysis, in this paper, a new muscle fatigue model was proposed. The new proposed model reflects the influence of external load, workload history, and individual differences. This model is simple in mathematics and can be easily applied in realtime calculation, such as the application in realtime virtual work simulation and evaluation. The new model was mathematically validated with 24 existing static models by comparing the calculated METs, and qualitatively or quantitatively validated with 3 existing dynamic models. The proposed model shows high or moderate similarities in predicting the METs with all the 24 static models. Validation results with the three dynamic models were also promising. The main limitation of the model is that it still lacks experimental validation for more dynamic situations. Relevance to industryMuscle fatigue is one of the main reasons causing MSDs in industry, especially for physical work. Correct evaluation of muscle fatigue is necessary to determine work-rest regimens and reduce the risks of MSD.

Predicting real-world ergonomic measurements by simulation in a virtual environment

“…Digital human modeling (DHM) and virtual human simulation (e.g., 3DSSPPÔ, EAI Jack Ò , RAMSIS) have been created to facilitate ergonomic evaluations (Ma et al, 2009a). Using these tools, the visual scope and reach envelope of users representing specific populations can be analyzed (e.g., EAI Jack Ò ) (Chaffin et al, 2001).…”

“…In the European Union, 40 million workers suffer from MSD, and the financial loss caused by MSD has been estimated at between 0.2% and 5% of GDP (Buckle and Devereux, 1999). Therefore, many researchers are focusing on analyzing potential MSD exposures and preventing MSD in work design (Ma et al, 2009a).…”

Multi-objective optimisation method for posture prediction and analysis with consideration of fatigue effect and its application case

“…As a result, the reduction process of the capacity decreases. This phenomenon is described by This model has been mathematically validated by comparing the existing static MET models and several dynamic muscle fatigue models (Ma, Chablat, Bennis, & Zhang, 2009). The observed strong correlations suggest that this model is suitable for static posture or slow operation.…”

“…Thus, there must be a compromise between the precision and the complexity of the model. In (Ma et al, 2009), different muscle fatigue models in the literature have been discussed, from the simple to complex ones. The existing muscle fatigue models are either too sophisticated for ergonomics analysis or too simple to integrate with the influences from external loads over time.…”

Upper-Limb Exoskeleton for Human Muscle Fatigue

“…Another ways to measure fatigue is by adding the fatigue model to the developed muscle model. [2][3][4] However, a limitation to the second approach is, it is difficult to acquire an accurate force distribution for each individu muscle. 4,5 Hence, 5 proposed a new fatigue model which using an information from joint level.…”