Department of Industrial Design, National Institute of Technology Rourkela, Rourkela, Odisha, India.
Chitkara University Institute of Engineerin and Technology, Chitkara University, Rajpura, Punjab, India.
Sci Rep. 2023 Jul 18;13(1):11619. doi: 10.1038/s41598-023-38592-x.
The examination of seated occupants' ride comfort under whole-body vibration is a complex topic that involves multiple factors. Whole-body vibration refers to the mechanical vibration that is transmitted to the entire body through a supporting surface, such as a vehicle seat, when traveling on rough or uneven surfaces. There are several methods to assess ride comfort under whole-body vibration, such as subjective assessments, objective measurements, and mathematical models. Subjective assessments involve asking participants to rate their perceived level of discomfort or satisfaction during the vibration exposure, typically using a numerical scale or questionnaire. Objective measurements include accelerometers or vibration meters that record the actual physical vibrations transmitted to the body during the exposure. Mathematical models use various physiological and biomechanical parameters to predict the level of discomfort based on the vibration data. The examination of seated occupants ride comfort under whole-body vibration has been of great interest for many years. In this paper, a multi-body biomechanical model of a seated occupant with a backrest is proposed to perform ride comfort analysis. The novelty of the present model is that it represents complete passenger by including thighs, legs, and foot which were neglected in the past research. A multi-objective firefly algorithm is developed to evaluate the biomechanical parameters (mass, stiffness and damping) of the proposed model. Based on the optimized parameters, segmental transmissibilities are calculated and compared with experimental readings. The proposed model is then combined with a 7-dofs commercial car model to perform a ride comfort study. The ISO 2631-1:1997 ride comfort standards are used to compare the simulated segmental accelerations. Additionally, the influence of biomechanical parameters on most critical organs is analyzed to improve ride comfort. The outcomes of the analysis reveal that seated occupants perceive maximum vibration in the 3-6 Hz frequency range. To improve seated occupants' ride comfort, automotive designers must concentrate on the pelvis region. The adopted methodology and outcomes are helpful to evaluate protective measures in automobile industries. Furthermore, these procedures may be used to reduce the musculoskeletal disorders in seated occupants.
对坐姿乘客在全身振动下的乘坐舒适性进行检查是一个复杂的课题，涉及多个因素。全身振动是指当车辆在粗糙或不平坦的表面上行驶时，通过支撑面（如车辆座椅）传递到整个身体的机械振动。评估全身振动下的乘坐舒适性有几种方法，如主观评估、客观测量和数学模型。主观评估涉及让参与者在振动暴露期间对其感知到的不适或满意度进行评分，通常使用数字量表或问卷。客观测量包括加速度计或振动计，用于记录在暴露期间传递到身体的实际物理振动。数学模型使用各种生理和生物力学参数根据振动数据预测不适程度。多年来，对坐姿乘客在全身振动下的乘坐舒适性的检查一直很感兴趣。在本文中，提出了一种带有靠背的坐姿乘客多体生物力学模型，以进行乘坐舒适性分析。本模型的新颖之处在于，它通过包括大腿、腿部和脚部来代表完整的乘客，而过去的研究忽略了这些部分。开发了一种多目标萤火虫算法来评估所提出模型的生物力学参数（质量、刚度和阻尼）。基于优化的参数，计算分段传递率并将其与实验读数进行比较。然后，将所提出的模型与 7 自由度商用汽车模型结合起来进行乘坐舒适性研究。使用 ISO 2631-1:1997 乘坐舒适性标准来比较模拟的分段加速度。此外，还分析了生物力学参数对最关键器官的影响，以提高乘坐舒适性。分析结果表明，坐姿乘客在 3-6 Hz 频率范围内感受到最大的振动。为了提高坐姿乘客的乘坐舒适性，汽车设计师必须专注于骨盆区域。采用的方法和结果有助于评估汽车行业的保护措施。此外，这些程序可用于减少坐姿乘客的肌肉骨骼疾病。
