Fender Design - Wheel Arch Challenge

Aim: To decide whether the given design passes the European standards or not.

Wheel Arch

• Wheel Arch is the semi-circular part of the fender positioned above the wheel of the vehicle.
• The design of the Wheel arch of a fender should be such that it must shield wheels and protect both passengers’ compartments and pedestrians from the projection of water, mud, and stones.
• For the vehicle to have its use permit in different countries, the wheel arch of fenders must be compliant with the standards and regulations set by the respective countries.

Given Design:

European Regulations Requirement:

1. Take the outline of the wheel and the fender.
2. Make the center of the wheel circle.
3. Draw horizontal and vertical perpendicular axes from the center of the wheel circle.
4. Draw lines at 30 degrees and 50 degrees from the center.
5. Make a point on the fender line at 150mm from the horizontal.
6. Extend a line to this point from the center.
7. Then make a line precisely between the 50-degree line and the line made on the 150mm point.

• Measure the distances between the points on the wheel circle and fender curve. All of these should be greater than 10mm to satisfy the European regs.
• Secondly, the horizontal distances from SA, SB, and SC point to the fender curve should be at least 5mm.
• Check whether the design passes these conditions and conclude whether it can give the European Regulations Requirement.

Challenge:

A sketch has been made.

Now let us measure the distances between the points in the 5 sections.

SA-SA

25.99 mm

SB-SB

43.64 mm

SC-SC

38.36 mm

SD-SD

41.24 mm

SE-SE

43.86 mm

Now find the horizontal distance between the wheel and the fender. This distance should be at least 5mm from the SA point, SB point, and SC point.

Project the made sketch onto the plane of the wheel.

Distance between SA point and fender outer curve = 10 mm (pass)

Distance between SB point and fender outer curve = 9.94 mm (pass)

Distance between SC point and fender outer curve = 0.11 mm (fail)

Conclusion:

The given design satisfies all European standards but one, i.e. the distance from the SC point to the fender curve (which is just 0.11 mm), which is way below the recommended 5 mm minimum distance. Therefore, this fender cannot pass European standards. The design should be reverted back to the class A designer telling him to modify the design and increase the gap there.