Fender Design - Wheel Arch Challenge

OBJECTIVE:

To calculate the wheel arc area and to prove whether the given fender of car will pass the European standards or not.

INTRODUCTION:

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. Corrosion had occurred around the splash plate at the back of the wheel arch.
• Wheel arch comes with some standard specifications. When viewed from the front or top side of the vehicle, if the wheel is protruding outside the fender, that would lead to more chipping while driving and compromises pedestrian as well as the vehicle safety. Taking these factors into consideration, the wheel has to be positioned inside the wheel.

FENDER:

• Fender is the part of a car that protects and frames its wheels and keeps mud from splashing it.
• Most modern vehicles have fenders on their front wheels. It is the part of a car, truck or motorcycle that surrounds the wheel sell.
• The primary function of a fender is to prevent dirt and debris from being thrown into the air by the tire.
• The fender is located over the wheels of the vehicle. As such, there are four fenders on a typical vehicle: front right, front left, rear right and rear left.

TYPES OF FENDER:

The type of fender is based upon the area covered

1. Full fender type
2. Half fender type

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.

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.

Case study:

Applying European standards to given Fender & wheel data:

There are different regulations in this regard based on different regions

JAPAN REQUIREMENTS FOR FENDER WHEEL ARC:

1. Measure clearance L of tire, hub, cap, and fender in three different positions within area K and produce clearance check chart to validate.
2. Clearance must be greater than 5mm in all the three positions.
3. Wheel guard requirement: the value a shall be more than 5mm at a line 30*forward and 50*rearward from the central vertical axis of axis of wheel.

US STANDARDS REGULATION FOR FENDER WHEEL ARC:

1. Make clearance check details on all positions from -100* to 100* and make the clearance check table.
2. All values should be greater than 5mm to satisfy the regulation.
3. The value of ‘a’ shall be more than 5mm at a line 30* forward and 50*rearward from the central vertical axis of axis of wheel.

EUROPEAN REGULATION:

• The sketch is drawn on the wheel face as per the European standards provided and projected on the wheel arch at section SA, SB, SC, SD, and SE to measure "L. "a" and wheel arch area.
• This case study has been done according to European regulations.

As explained in the diagram below, the minimum clearance 'L' recommended at all the 5 points on the wheel arch shown here should be 5-10mm, the points being SA, SB, SC, SD, SE.

Procedures

• A horizontal and vertical Axis is drawn from the centre of the wheel.
• The vertical axis intersection point is labeled as SA.
• Similar references are drawn at 30 degree to the left and 50 degree to the right of the section SA and are named SB and SC respectively.
• A line of 150mm is drawn perpendicular to the horizontal axis and the normal from that point on the fender gives us SE.
• The midpoint of the arc cut by the sections SC and SE results in a new section SD.
• The value of 'L' at each section and the value of 'a' are found out to determine whether the fender satisfies the European standards as shown below.

'L' Value at Section SA-SA: 9.994mm

'L' Value at Section SB-SB: 10.00mm

'L' Value at Section SC-SC: 0.113mm

'L' Value at Section SD-SD: 2.887mm

'L' Value at Section SE-SE: 5.997mm

Clearance 'a' at 30 degree line: 43.62 mm

Clearance 'a' at 50 degree line: 38.55mm

SECTION	REQUIRED CLEARENCE	ACTUAL CLEARENCE	RESULTS	‘a' clearance(>5MM)	RESULTS
SA-SA	10mm	9.949mm	fail
SB-SB	10mm	10.00mm	pass	49.64mm	pass
SC-SC	10mm	0.113mm	fail	43.64mm	pass
SD-SD	10mm	2.887mm	fail
SE-SE	10mm	5.997mm	fail

CONCLUSION:

From the above results it conclude that the fender does not pass the European regulations,

The minimum clearance L between the fender wheel arch and wheel for vehicle and pedestrian safety is 10mm and this design does not meet the requirement.