Fender Design - Wheel Arch Challenge

FENDER WHEEL ARCH CHALLENGE

FENDER 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 the fender should be such that it must shield wheels and protect both passengers compartment and pedestarians from the projection of watr, mud and stones.The wheel arch area of the fender is usually designed as a cover or shield over the tyre along its perimeter to stop any debris or stones ,dirt,sand,snow,etc,from getting thrown into the vehicle or the BIW area as well as outside the vehicle and onto other vehicles or pedestarians on the road.For the vehicle to has its permit in different countries,the wheel arch of fenders must be compliant with the standards and regulations set by respective countries.

TYPES OF FENDER:

The type of fender is based upon the area covered i.e., full fender type and half fender type.

1. FULL FENDER TYPE: Full fender type is traditional type of fender where more material consumption is observed. This type is used in old design of automobiles where it increases the overall weight and thus reduces performance. The maintenance also relatively more due to more surface.
2. HALF FENDER TYPE: Half fender type is modern design where less material consumption is observed, so productivity increases by reducing size of blank and thus providing more performance. The maintenance also relatively low compared to full bumper type.

European Regulations :

The European regulations requires a pre-determined clearance or a minimum distance of 10mm to be maintained between the fender and respective tyre at particular points, along the tyre profile as shown below:

• The clearance "L" should be measured at sections SA-SA, SB-SB, SC-SC, SD-SD and SE-SE and create clearance check chart to validate.
• At all the five sections the value of L should be greater than 10mm to satisfy the European Regulations.
• Wheel guard requirement : The value of "a" should be more than 5mm at line 30degree forward and 50degree rearwards from the central vertical axis of the wheel.

Calculations of wheel Arch area - European Regulations

For calculation of clearance between wheel Arch and wheel we have to create a sketch on the outer most face of the wheel and the procedure as follows.

From the given part file we need to open in the NX cad and from the part file they give the fender and the wheel. So, now we need to check for the European regulations standard. Now we need to create the Datum plane at the outer most face of the wheel as shown in figure.

After that in that plane we sketch the lines and the give the required angle from the reference of the European standard drawing by using the Rapid dimension as shown in figure.

PROCEDURE:

1. According to the European standards, the design fender and wheel arc should pass the wheel guard requirement procedures.
2. To start the test, first create a plane with origin as center of the wheel plane.
3. Then sketch using lines along with given dimensions as SA, SB, SC, SD and SE.
4. After sketching project the intersection points on to the fender face.
5. Then use measure distance tool and calculate the clearance between sketch lines and wheel arc.

6.The clearance between SA line and wheel arc is 10mm also the line SA lies inside the fender so it is negative value.

7.The clearance between SB line and wheel arc is -9.9490mm also the line SB lies outside the fender so it is positive value.

8.The clearance between SC line and wheel arc is -0.1139mm also the line SC lies outside the fender so it is negative value.

9.The clearance between SD line and wheel arc is -2.8875mm also the line SD lies outside the fender so it is negative value.

10.The clearance between SE line and wheel arc is -5.9973mm also the line SE lies outside the fender so it is negative value.

RESULTS:

Section	Clearence "L" 10(in mm)	Comments
SA	10mm	pass
SB	-9.9490mm	Fail
SC	-0.1139mm	Fail
SD	-2.8875mm	Fail
SE	-5.997mm	Fail

Conculusion:

From the above results we can conclude that the Fender does not pass the European Regulations, as the minimum clearance L between the Fennder Wheel Arch and Wheel for vehicle and pedestrian safety is 10mm and this design does not meet the requirement.