The Study On The Ergonomic Of Firefighters’ Personal Protective Clothing Based On 3D Motion Capture

In order to reduce the casualties of firefighter,this paper takes the individual protection as the guide,combined with ergonomics,and the 3D motion capture technology was applied to the research on the ergonomic of personal protective clothing(PPC).The ergonomic evaluation index system and the quantitative research on the impact of PPC on human mobility with"multiple clothing,multiple sports states,multiple body parts,and subjective and objective combination" was realized in this study.The main work and research results are as follows:Twenty participants were recruited for human movement experiments with four different clothing for static and dynamic activities,and the human movement data measured by the 3D motion capture system was converted into PPC ergonomics performance evaluation indicators through calculation.The differences in ergonomics between different PPCs were compared,and the subjective evaluation scores of the rating of perceived exertion(RPE)and the restriction to movement during the experiment were collected.The quantitative expression of the subjective and objective evaluation indicators of the ergonomic of PPC was proposed through the correlation analysis,and the influence of different PPCs on the mobility of different parts of the firefighter’s body was compared and analyzed.The results showed that:compared with basic clothing,PPC has a significant impact on the range of motion(ROM)and operational flexibility,and improves the RPE and the restriction to movement during activities.In particular,shoulder abduction was significantly reduced by the limitation of PPC in static activities(25.9%-40.2%,p<0.05),and in dynamic activities,hip(extension angle increased by 27.2%),knee(landing angle increased by 75.4%)and ankle(plantarflexion angle increased by 11.4°-13.1°)were both affected by PPC resulting in significantly lower gait speed,stride frequency,and stability(p<0.05).This may lead to a decrease in firefighters’ rescue efficiency in fires and increased risk of slips,falls,and trips(STF).In addition,the subjective and objective evaluation indicators of ergonomic of PPC were significantly correlated:clothing mass not only directly affected ROM(r=-0.521,p<0.01),but also positively affected RPE by restricting movement,and then indirectly negatively affect ROM.The greater the mass of clothing,the greater the degree of restriction to movement,the greater the RPE,the lower the ROM of the joints,and the mediating effect was significant(c=-0.110,p=0.026).Therefore,reducing the mass of PPC,using soft uppers and soles,and increasing the pleated design of the shoulders can all help reduce RPE and improve comfort,thereby improving the performance of firefighters’ movement.These findings identify specific body parts in which differences between the PPCs were identified,thereby supporting a systematic and comprehensive ergonomic evaluation of PPC to guide the improvement of personal protective equipment systems.It can provide basic data for the development of high-performance PPC,and provide theoretical guidance for the training and actual combat of emergency rescue of firefighter.