Fender Design - Wheel Arch Challenge

Aim:-

To Calculate the Wheel Arch gap at required points and checks whether the car passes the Eurepean standard.

Fender:-

A fender is a part of the automobile that is placed just above the tyres/wheels (both of the front and back). The purpose of the fender in an automobile is to prevent sand, mud, rocks, liquids, and other roads spray from being thrown into the air by the rotating tire. 

Below is an example of the front fender of a car:

Fender ia an American English term whereas in Britain and India it is called Wing and Mudguard respectively. The fender's openings for the wheel wells tend to be much larger than the diameter of the tire because they do not move 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:-

 Wheel Arch is the semi-circular part of the fender positioned above the wheel of the vehicle. The main role of wheel arch is it protects both passenger’s compartment and pedestrians from the projection of water, mud and stones. The wheel arch area 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 onto other vehicles or pedestrians on the road. Different countries have different wheel arch regulations and the wheel arch design has to comply with them to be deemed usable in that country.

It is a curved part of the fender positioned right above the wheel. The Wheel Arch is designed such that it protects both the pedestrian and car cabin from mud, water rocks and other road spary. Different countries have different wheel arch regulations in place, and the wheel arch design has to comply with them deemed usable in the country.

            

For avoiding design atterations of the same vehicle to meet the different regulations paramerters are taken into consideration for design purpose.

TYPES OF FENDER:

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

Full bumper type :

Half bumper type :

Fender Wheel Arch Regulations:

Japan Regualtions:

• 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 pasitions.
• Wheel guard requirement : The vlaue of 'a' should be more than 5mm at line 30 degree forward and 50 degree rearwards from the central vertical axis of the wheel.

 

US Regulations :

• Clearance 'L' is to be  checked at all positions from -100 degree to 100 degree and create clearance check chart to validate.
• The value of L should be greater than 5mm to satisfy the regulations.
• Wheel guard requirement: The value of 'a' should be more than 5mm at line 30 degree forward and 50 degree rearwards from the central vertical axis of the wheel.

European Regulation:

• 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 30 degree forward and 50 degree rearwards from the central vertical axis of the wheel.

Calculation of Wheel arch area according to European Regulations :

• A Datum plane is created at the outermost face of the wheel .
• Horizontal and vertical line is created from the center of wheel and make it  reference.
• Create 30 degree and 50 degree line with respect to vertical line .
• Now take offset of 150mm from the horizontal line .
• Now create 5 point on plane and project it into the fender.
• Now measure the clearance 'L’.

Why they have different requirements ?

• This is because of the road condition and also due to population density at the particular country.
• As in japan population density is high means speed limit will be low due to which at low speed the mud partical will spread slow so it have less distance ( 5mm) .
• While in europ population density is less means speed limit will be high due to which at high speed the mud partical will spread fast so it have more distance (10mm ) 

We have to Calculate the Wheel Arc area and prove whether the car will pass the standards or not under European Regulation

Find the Wheel Arch Area in European Regulation:

Procedure:

• According European Standards, for calculation of clearance between wheel arch and wheel we have to create a sketch on the outer most face of the wheel.
• First create a plane on the outer most of the wheel, with origin as center of the wheel plane.
• Then sketch using lines along with given dimensions as SA, SB, SC, SD and SE.
• After sketching project the intersection points on to the fender face.
• Then use measure distance tool and calculate the clearance between sketch lines and wheel arc.

Cleareance between SB line and Wheel Arch is : 10mm.

Cleareance between SA line and Wheel Arch is : 9.9489mm.

Clearance between SC and Wheel Arch is : 0.112764 mm.

Cleareance between SD line and Wheel Arch is : 2.8878 mm.

Cleareance between SE line and Wheel Arch is : 5.9020 mm.

Region	Required Clearance	Actual Clearance	Results
SA	10mm	9.9489mm	Fail
SB	10mm	10mm	Pass
SC	10mm	0.112764mm	Fail
SD	10mm	2.8878mm	Fail
SE	10mm	5.9020mm	Fail

Conclusion:

 The given Fender is Fail the European Regulation for Wheel Arch Area. Because of clearance value is varies between the section to section. Due to the Tire is go outside direction. So, it is danger for pendestrian safety.