Fender Design - Wheel Arch Challenge

FENDER

Fender is the American English term for the part of an automobile, motorcycle or other 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. Fenders are typically rigid and can be damaged by contact with the road surface.

Sticky materials, such as mud, may adhere to the smooth outer tire surface, while smooth loose objects, such as stones, can become temporarily embedded in the tread grooves as the tire rolls over the ground. These materials can be ejected from the surface of the tire at high velocity as the tire imparts kinetic energy to the attached objects. For a vehicle moving forward, the top of the tire is rotating upward and forward, and can throw objects into the air at other vehicles or pedestrians in front of the vehicle.

REGULATIONS

Vehicle regulations are requirements that automobiles must satisfy in order to be approved for sale or use in a particular country or region. There are various s that are available depending upon different countries. Some of the regulations that are used by Indian automotive industries are ARAI, SAE.

JAPAN REGULATIONS

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 degree forward and 50 degree rearward from the central vertical axis of axis of wheel.

US STANDARDS REGULATION

1. Make clearance check details on all positions from -100degrees to 100degrees 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

1. Measure CL L at section SA-SA-SB-SB-SC-SC-SD-SD-SE-SE and produce CL check chart to validate.
2. At all five sections the CL L value should be greater than 10mm to satisfy the European regulations.
3. Wheel guard requirement: 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.

PROVIDED WHEEL ARCH FOR CHECKING CLEARANCE

PROCEDURE

• A Datum Plane is created at the outermost face of the wheel
• The sketch is created on the new Datum Plane
• A Horizontal line is drawn across the centre of the wheel
• A perpendicular line SA is dropped at the centre of the wheel
• Two lines SB and SC are created at 30° forward of SA and 50° rearward of SA respectively
• A point is created 150mm vertically above the centre line
• A line SE is drawn from the wheel centre and passes from the point created
• Another line SD is drawn from the centre of the wheel and in the middle of lines SC and SE
• Points created on the intersection of projected border line of the fender is projected on to the surface of the fender
• Measurements are taken

i.) Clearance 'L' at SA = 9.949

ii.) Clearance 'L' at SB =10.0

iii.) Clearance 'L' at SC=0.1139

iv.) Clearance 'L' at SD=2.890

v.) Clearance 'L' at SE=5.997

Measuring the clearance vlaue'a' for Wheel Guard Requirement

i.) Clearance 'a' at 30° line SB

a = 43.62mm

ii.) Clearance 'a' at 50° line SC

a= 38.35mm

RESULT

REGION	CLEARANCE	RESULT	(a>5mm)	RESULT
SA	9.94	FAIL
SB	10.00	PASS	43.62	PASS
SC	0.11	FAIL	38.3599	PASS
SD	-2.8904	FAIL
SE	-5.9973	FAIL

CONCLUSION

The value of Clearance (L) is measured at all five location and tabulated. The result shows that only the section SB have 10 mm clearance and at remaining four sections value is less than 10mm. According to the data collected, the given fender does not qualify the European standard for wheel arc area.