ABSTRACT
@#Driving posture is one of the factors that need to be emphasized in ensuring driver’s comfort and to avoid road accidents and injuries. Meanwhile, fatigue has a strong relationship with comfortable posture and it contributes 15.7% of the total road accidents in Malaysia. Fatigue can reduce driving concentration and performances, thus increases the risk of road accidents and injuries. In order to determine the driver’s comfort, this study had measured muscle contraction using the objective measurement for comfortable and optimum driving posture angles. The equipment used for conducting objective measurement on 14 respondents was sEMG. The researcher had used sEMG equipment to evaluate muscles activities at upper extremities, which comprises of Biceps Brachii (BB), Deltoid Anterior (DA) and Trapezious Upper (TU) that were involved during controlling the car steering. It involves three driving postures parameters according to the fixed elbow and shoulder angles. The results from this study showed the BB muscle increased positively when turning the steering wheel to the right within 3 to 6 times value increased. Meanwhile, DA and TU muscles experience a contraction in the opposite direction with steering wheel turning action, which shows higher right side DA and TU muscle contraction when the driver turn the steering to the left with around 80% decrease for DA and within 60% to 80% decrease value for TU. BB muscle also shows an increasing value of muscle contraction with higher elbow flexion, meanwhile DA and TU muscles contraction also show an increment in-line with greater shoulder abduction. The results showed that posture B with elbow angle at 36° and shoulder angle at 134° are the most comfortable driving postures, hence the lowest muscle contraction value of 15.67μV (BB), 19.31μV (DA) and 12.36μV (TU) compared to the other two measured postures. The results of muscle contraction from this study is capable of assisting researchers and car manufacturers to understand the relationship of steering maneuvering when developing more comfortable and suitable vehicle’s driver seat compartment.
ABSTRACT
@#Discomfort and pain issue at the body part are common complaints reported by car drivers. It is due to driving task require physical demands and need to maintain and adapt several postures in a constrained space while controlling the car. Hence, this study aims to determine the pattern of shoulder activation muscle consisting of the Trapezius muscle in two different driving posture. Respondents were required to grasp the steering wheel at 8 and 4 hand position. The Surface Electromyography was used to get the reading for left muscle’s Trapezius Descendent (TD) at two different positions; i) closest distant from steering wheel and ii) far distant from the steering wheel. Then, Temporal Analysis was used to evaluate the pattern of the driving action. From the experiment, it shows the different value of muscle activation occurred while driving according to turning action. The far seated position depicted greater activation on driving action compared to the closer seated to the steering wheel. In conclusion, the driving posture effects the activation of shoulder and arm’s muscles as early as after 20 seconds of driving activity. Hence, choosing the correct driving posture allowed a comfortable driving environment for the driver.
Subject(s)
Superficial Back MusclesABSTRACT
@#While driving, a driver is required to control the steering wheel to change direction. The driver’s muscles of the upper limbs and shoulders are involved in such a task. Therefore, an assessment of the driver’s physiology according to certain condition is necessary to improve driving comfort and safety. This study aims to investigate the driver’s Deltoid Anterior (DA) muscle activity while operating the steering wheel. Eleven test subjects were recruited for an experiment using a car simulator. They were required to remain in the car seat and perform the task of steering the wheel. Surface electromyography (SEMG) was used to record each subject’s muscle contraction while turning the steering wheel to the right and left by several degrees. According to the findings, 45 degrees turning recorded the highest Root mean Square (RMS) value for DA. In addition, DA muscle activation increased with more degrees turning.