Fender Design - Wheel Arch Challenge

Fender

objective:-

To Calculate the wheel arch radius for the given Fender model and check for its eligibility to pass the European Standards.

Introduction:-

Fender is the US English term for the part of an automobile (vehicle body) that frames a wheel well (the fender underside).

Its primary purpose is to prevent sand, mud, rocks, liquids, and other road spray from being thrown into the air by the rotating tire.

When vehicle is moving, tires pick up stones and others and hurl them in all directions. Fenders are basically present to prevent any injuries to pedestrians and contain the motion of these particles.

Most passenger automobiles have four fenders, one over each wheel. For vehicles with a narrow car body that exposes the tire, the fender is an exposed curve over the top of the tire. For wide body vehicles that cover the tire, the fender forms the wheel well surrounding the tire, and is not directly visible from above the car body.

Wheel wells tend to be much larger than the diameter of the tire, because they do not move with the tire suspension and consequently must be large enough to allow the full range of tire motion on the suspension without touching the interior of the wheel well.

Wheel Arch :-

The wheel arch is the semicircular part positioned above the wheel of a vehicle. The most important body change was that the front wheel arch was cut higher into the fender.
Their are some different regulations to the wheel arch calculation by different country as follow :-

1. JAPAN REGULATIONS

Measure clearance L. of tire,hub, cap & fender in three different positions within area K and produce clearance check chart to validate

Clearance must be greater than 5 mm in all the three positions.

Wheel guard requirements The value of 'a' shall be more than 5 mm at a line 30 forward and 50" rearward from the central vertical axis of axis of wheel.

2. EUROPEAN REGULATIONS

Measure clearance L at sections SA-SA SB-SB SC-SC SD-SD SE-SE and produce clearance check chart to validate.

At all five sections the clearance L value should be greater than 10 mm to satisfy the European regulations.

Wheel guard requirements The value of 'a' shall be more than 5 mm at a line 30° forward and 50" rearward from the central vertical axis of axis of wheel.

3. US REGULATIONS

Make clearance check details on all positions from -100* to 100* & make the clearance check table.

All values should be greater than 5 mm to satisfy the regulations.

The value of 'a' shall be more than 5 mm at a line 30 degree forward and 50 degree rearward from the central vertical axis of axis of wheel.

For this case we have check the given part is satisfying the conditions for regulation of the EUROPEAN REGULATIONS.

Procedure

1) Take a plane on the face of the wheel and create a certical straight line SA from the centre of the wheel

2) Create two similar lines SB & SC at 30 degree and 50 degree angle respectively from the line SA taken from the centre

3) Create a horizontal line passing from the centre on the wheel and offset it to 150 mm upwards, and mark its point of intersection with the edge of the wheel

4) Draw a line passing throgh centre of the wheel and intersection point. Create angle bisector using bisecting lines and name the two new lines created as SD & SE

5) Exit the sketch and measure the distance between the Fender outer edge and the lines drawn on the wheel.

For SB

For SA

For SC

For SD

For SE

SR NO.	Point	Distance [L]	Pass/ Fail L>10
1	SA	9.94	Fail
2	SB	10.00	Pass
3	SC	0.11	Fail
4	SD	2.88	Fail
5	SE	5.99	Fail

Wheel guard requirements

Same way we have take the intersection point on the wheel edge and the line which we have drawn on planeand measure the distance between the projection point on the fender to the intersection point on the wheel edge. It should be greater than 5mm at a line 30° forward and 50" rearward from the central vertical axis of axis of wheel.

For SB'

For SA'

For SC'

For SD'

For SE'

SR NO.	Point	Distance [a]	Pass/ Fail a>5mm
1	SA'	30.99	Pass
2	SB'	48.62	Pass
3	SC'	43.35	Pass
4	SD'	47.66	Pass
5	SE'	52.62	Pass

CONCLUSION:

Only the Lines SB which is greater than 10 mm from the fender outer and Wheel guard requirements for all the points /lines, satsify the Eurpean standard whereas the other lines/points doesnt. Hence we have to discuss with the styling team and give our inputs to change the styling of the Fender to satisfy the European Standards.

Hence, the Given Fender model doesnt Pass the European Standards and need to be modified.