A DUMMY FOR REPRODUCING THE HUMAN WHOLE BODY VIBRATION

摘要

The paper presents an innovative dummy conceived to provide an effective tool for an objective vehicle ride comfort evaluation. The first part of the research includes experimental tests on instrumented seats for evaluating the vertical (cushion) and longitudinal (backrest) acceleration between the vehicle seat and the seated human subject. Experiments have been performed by using a vibrating table fitted with a vehicle seat and by seating directly the subjects on vehicles (cars and light trucks) while running on a test track. The test track includes uneven road and different obstacles. Human subjects have been chosen in order to obtain a high variability in the anthropometric features (height, weight, gender, age). Several test have been also performed with the same subject submitted to the same excitation in order to investigate the inter-subject variability and the intra-subject variability. During the study different seats have been compared. From the acquired data, a mathematical model of the system, human subject + seat has been derived and numerically validated by minimizing the error between the measured and the computed accelerations. The corresponding mechanical device has been built, the MaRiCO dummy. The device is fully adjustable in order to simulate the vibrational behaviour of different human subjects. Particular attention has been devoted to the construction of the springs and of the magnetic damper to reduce as much as possible the friction between the moving components. The dummy rests on the seat by means of special elements that, thanks to their compliance and conformation, act as the tight and the back of human beings. An experimental validation of the dummy has been performed. The device, opportunely tuned and seated with the same posture of the corresponding human subject is able to reproduce the acceleration between the subject and both the cushion and the backrest.