Fender Design - Wheel Arch Challenge

Aim:

To calculate the Wheel Arch gap at required points and check whether the car passes the European standard.

Theory-

Fender:

A fender is a part of an automobile, motorcycle, or other vehicle body that frames a wheel well. Its primary purpose is to prevent sand, mud, rocks, and other road sprays from being thrown into the air by the rotating tire. Fenders are typically rigid and can be damaged by contact with the road surface.

The main purpose of fenders on cars is that they shield the wheels and they protect the passengers, pedestrians, and other vehicles from the stones, mud, and other debris that can fly in the air because of the speeding rotating wheels while the car is running.

Wheel Arch:

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

Fender Wheel Arch Regulations :

Japan Regulations :

• The clearance "L" for tire, hub, cap and fender is to be measured within area K and create clearance check chart to validate.
• The value of L should be greater than 5mm at all points.

Wheel guard requirement : The value of "a" should be more than 5mm at line 30° anticlockwise and 50° clockwise from the central vertical axis of the wheel.

European Regulations :

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

US Regulations :

• Clearance "L" is to be checked at all positions from -100° to 100° and create clearance check chart to validate.
• The value of L should be greater than 5mm to qualify the US regulations.
• Wheel guard requirement : The value of "a" should be more than 5mm at line 30° anticlockwise and 50° clockwise from the central vertical axis of the wheel.

PART A:-

Calculation of wheel arch area according to European regulations:

1. A datum plane is created at the outermost face of the wheel.
2. The sketch is created on the new datum plane.
3. A horizontal line is drawn across the center of the wheel.
4. A perpendicular line SA is dropped at the center of the wheel.
5. Two lines SB and SC are created at 30 degrees forward of SA and 50 degrees rearward of SA respectively.
6. A point is created 150mm vertically above the center line.
7. A line SE is drawn from the wheel center and passes from the point created.
8. Another line SD is drawn from the center of the wheel and in the middle of lines SC and SE.

Sketch:

Calculation of the value of clearance "L":

The clearance "L" as shown in the above figure at all the five sections SA, SB, SC, SD, SE should be greater than 10mm.

1. Measuring "L" for the given wheel and fender at SB

the value of "L" at SB= 10.00 mm.

2. Measuring "L" for the given wheel and fender at SA

the value of "L" at SA= 9.94 mm.

3. Measuring "L" for the given wheel and fender at SC

the value of "L" at SC= 0.113mm.

4. Measuring "L" for the given wheel and fender at SD

the value of "L" at SD= 2.88 mm.

5. Measuring "L" for the given wheel and fender at SE

the value of "L" at SE= 5.9973 mm

TABLE A :Clearence "L" obtained at sections SA,SB,SC,SD and SE

Section	Clearence "L" 10(in mm)	Comments
SB	10<=10	Pass
SA	9.950<10	Fail
SC	0.113<10	Fail
SD	2.886<10	Fail
SE	5.997<10	Fail

From table ,the given fender does not pass the European Standards for the Wheel arc area at sections SA,SC,SD and SE

PART B :-

Obtaining the values of cleareance "a" for wheel Guard Requirements

a)Finding the values of "a" at line 30 deg forward from center vertical axis of the wheel.

The value of "a" at line 30 deg forward from center vertical axis of the wheel =44.75 mm

b)Finding the value of "a" at line 50 deg rearward from centre vertical axis of the wheel.

The value of "a" at line 50 deg rearward from centre vertical axis of the wheel=38.359 mm

TABLE B: Clearence "a" obtained at section SB (AT 30 deg forward from centre axis),SC(at 50 deg rearward from centre axis)

Section	Angle(in deg)	CLearence	Comments
SB	30	44.754>5	Pass
SC	50	38.359>5	Pass

From table B,the given fender passes the European standards for wheel arch area only in the case of cleareance "a"

Conculusion:

From the above results obtained, we can conclude that the given fender doesn't pass the European Standards for Wheel Arch Area.