# Methodology Proposal, Virtual Simulations and 3D Printed Prototype of a Car Steering Wheel
## 2 Methodology of Vehicle Steering Wheel Simulations
### Preparatory Stage
#### 2.1.2 Defining Material Characteristics  
An important subphase is the selection of a suitable material or several materials from which the individual parts of the assembly will be printed using 3D printing technology. When selecting suitable materials, it is necessary to define the individual requirements that must be met in order for the new prototype to meet the following requirements:  
* Material strength  
The steering wheel is part of the car's control unit and is subjected to a strength test many times in the event of an accident. In a head-on collision, the driver of the car exerts his own weight on various places on the steering wheel, which must withstand the load of both the strapped and unrestrained driver. It is, therefore, very important that the steering wheel material is sufficiently resistant to unexpectedly high loads. * UV stability  
Many cars are not garaged and are constantly exposed to sunlight. The selected materials must be resistant to sunlight and must not degrade their properties under its influence, such as strength and color fastness. * Resistance to high and low temperatures  
The interior temperature of a car can reach up to 30 degrees Celsius higher than the outside temperature in summer, especially if it is a black car. When it is a mild 35 degrees outside, it can be a deadly 65 degrees inside, while the steering wheel and dashboard, which are black and absorb heat, can be even twenty degrees warmer, the total temperature reaches up to 85 degrees Celsius, where there is already a risk of skin burns when hands  
Figure 1: 3D model source data (exploded state). touch such a surface. Also, during the winter, there is a dramatic cooling in non-garaged cars. The selected material should be able to withstand temperatures in the range of \(-60\)\({}^{\circ}\)C to +110 \({}^{\circ}\)C.  
* Color variability  
The solution will include colorful personalized elements that will complement the interior of the car according to the customer's requirements. The development of various materials for 3D printers is unstoppable, but it is possible that the material that would meet all the previous requirements will not be in the desired color variations. In this case, it is possible to use different color shades of additional spraying. After examining the material characteristics of the available 3D printer cartridges [29] and other detailed data sheets, the following materials meet the required criteria:  
1. Material: ABS-M30 (Acrylonitrile Butadiene Styrene--Thermoplastic Copolymer)  
The M-30 type is 25 to 75% stronger than conventional ABS (depending on the manufacturer). It has suitable mechanical properties and is ideal for the production of functional models, prototypes, fixtures, and tools. It perfectly resists low and high temperatures, and its partial deformation is observed from +98 \({}^{\circ}\)C. It shows high resistance to UV radiation. 2. Material: PC-ABS (Polycarbonate and Acrylonitrile Butadiene Styrene--Thermoplastic Composite)  
This type of material combines the advantages of PC and ABS, and it is characterized by a very good ratio of functionality and machinability. The mixture of polycarbonate and ABS shows a synergistic effect, which results in excellent strength and impact resistance even at low temperatures, which is even better than the impact resistance of ABS or PC alone. It perfectly resists low temperatures and high temperatures up to +125 \({}^{\circ}\)C.  
3. Material: ASA (Acrylonitrile-Styrene-Acrylic--Thermoplastic)  
The material is characterized by excellent UV resistance, good mechanical resistance, rigidity, and resistance to high temperatures. Other benefits include easy workability on 3D printers, print quality even with demanding details for small objects, excellent layering of the printed object, excellent weather resistance, and preservation of physical properties. 2.2. Virtual Simulation Phase  
Simulations will be carried out using CAE (Computer Aided Engineering) applications.