# The Effect of Vibrations from Racing Cars on the Human Body in FORMULA STUDENT Races
## 1 Introduction
To control vibrations and limit their unwanted effects, it is necessary to design, model, and simulate the vehicle's suspension system. Suspension systems are responsible for mitigating roadway disturbances. An analysis of a vehicle used in Formula Student races is made in [32]. Finite element analysis is performed using the ANSYS (R) Workbench. For the vibration isolation of the single-seater, a solution was used that consisted of a support made of elastomer used to isolate the vibrations reaching the vehicle structure [33]. The high level of transmissibility of a racing car was highlighted, which is also manifested by the high noise produced by such a vehicle. The factors that determine people's opinions on the comfort level of the vehicle are physical variables such as temperature, vibrations, air speed, acceleration, light intensity, and noise level. A study that aims to objectify people's subjective evaluations of comfort is presented in [34]. Based on them, the study of measurable variables at certain points of a mannequin makes it possible to establish comfort indices. The study of the kinematics of the driver's head and his exposure to accelerations and vibrations is analyzed in [35]. Experimental data for the study was collected using six race drivers. The study also allowed a measurement technique that allows decoupling acceleration in turns from those due to short-term disturbances. Other theoretical models and measurement techniques for the determination of accelerations and vibrations occurring in machines subjected to high forces are presented in [36; 37; 38; 39; 40; 41; 42]. Racing drivers are exposed to intense whole-body vibrations. These vibrations are complex, involving movement along multiple axes in both the sagittal (e.g., vertical) and coronal (e.g., lateral, roll) planes of the human body [43]. Previous research has shown that the human body is a non-linear system, but the vibrations along a single axis have been analyzed by most researchers, as they can give a first-instance characterization of the demands to which the driver can be subjected [44; 45; 46]. The limits of the different sizes that the human body can bear under the action of vibrations are standardized [47; 48]. The study of vibrations was done, on most models, only on the human body (i.e., see [49], where the natural frequencies were determined for a human body). In this work, we tried to cross this limit by studying the racing car-human body assembly. Obviously, such an approach requires increased computing resources, but current technology can provide us with these resources. Numerous works deal with the study of the damping effect that the seats and their material can have on the damping of the vibrations acting on the driver [50; 51; 52; 53; 54; 55; 56; 57; 58; 59; 60]. In general, there are few studies that present human behavior during vibrations to which he is subjected while driving a vehicle. The studies are done for relatively low RMS values of the accelerations (3 m/s\({}^{2}\)). The accessible values to which the human body can be subjected are indicated in [61]. When driving on bumpy roads, drivers and passengers are exposed to extensive vibrations of the whole body and repeated shocks. The vibrations lead to a response of the human body which is generally non-linear. This paper presents the vibrations of three distinct human body points under various conditions. These are contrasted with one another. The circumstances surrounding a race car are examined, and the amplitudes of three dummy points are determined in the event that the car experiences excitation in three distinct scenarios. Scenarios where we are in the vicinity of resonance vibrations, where the vibrations' amplitude grows are examined.