Fender Design - Wheel Arch Challenge

Objective

To calculate the wheel arc for given Fender model, by means of the European standards regulations.

Introduction

Wheel arc calculation is necessary for the fender design to pass the local regulation which are based on the local road conditions.

Wheel arch is a semi-circular area in fender, which houses the wheel well. It should have a sufficient clearance between tyre and wheel arch. So, that it doesn’t touch the wheel arch area during suspension. The clearance value differ from region to region, here are few regulations.

Japan Regulation Standard:

The clearance value will be more than the 5mm at 30 degree at forward and 50 degree at backward from the central vertical line.

European Regulation Standard:

The clearance value will be more than 10mm at 30 degrees at forward and 50 degree at backward and line 150mm above X-axis and Mid-point between 50 degree and line above 150mm.

US Regulation Standard:

Make clearance check details on all position from -10 to 180 degrees. All values must be greater than 5mm.The Clearance Value will more than 5mm at line 30 degree forward and 50 degree backward from central vertical axis.

Wheel Arc Calculation

This is carried out for pedestrian safety of the car, here by using the European regulations requirement to define the design given for calculation.

As required to plot the coordinates,

Following coordinates SB, SB, SC, SD and SE are plotted using the angles and dimensions according to the requirement standard.

Next the points are checked if they provide a gap of 10mm from the outer part of fender to the outer most part of the tier, if it is more than 10mm it meets the safety requirement if it is below 10mm it doesn’t meet the standard.

You can see the law extension of 10mm towards the fender is done, we can see that SA, SB have a clearance more than 10mm whereas remaining check points doesn’t meet the standard.

SB plot satisfies the 10mm distance

SA plot satisfies the 10mm distance

SC plot doesn’t satisfy, there is 3mm clearance which doesn’t go with the standard.

SD plot doesn’t satisfy, there is 0.25mm clearance which doesn’t go with the standard.

SE Plot doesn’t satisfy, there is -3.4mm clearance which doesn’t go with the standard.

Conclusion

Hence we can declare that the following fender wouldn’t pass the standards the styling team must redesign the fender.