Fender Design - Wheel Arch Challenge

Fender Design - Wheel arch measuring by European Standards

Objective :

• To measure the wheel arch gap at required points and check whether the car passes the European standard.
• Study about the different wheel arch gap standards.
• Draw the lines at the required angle and points for the European standard.
• Measure the distance at each angles and mention given model is pass or fail.
• Reference fender design wheel arch master sketch given below
• 

Fender :

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

Wheel Arch :

• 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 spray. Different countries have different wheel arch regulations in place, and the wheel arch design has to comply with them to be deemed usable in that country.
• For avoiding design alterations of the same vehicle to meet the different regulations parameters are taken into consideration for design purpose.

Fender Wheel Arch Regulations :

There are different types of fenedr wheel arch regulations

1. Japan Regulations

2. European Regulations

3. USA Regulations

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

2. European Regulations :

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

3. USA Regulations :

• 
• Clearance "L" is to be checked at all positions from -100degree to 100degree 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 30degree forward and 50degree rearwards from the central vertical axis of the wheel.

Calculations of wheel Arch area - European Regulations :

• Wheel Arch is the semi-circular part of the 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 projection of water, mud and stones. The wheel Arch area of the fender is usually designed as a cover or sheild over the tyre along its perimeter to stop any debris or stones, dirt, sand, snow etc. from getting thrown into the vehicle/ BIW area as well as outside the vehicle and onto other vehicles or pedestrians on the road. 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.
• The European regulation requires a pre determined clearance or a minimum distance of 10mm. to be maintained between the Fender (Front Quarter Panel) and the respective tyre at particular points(5 points/Sections to be exact) along the tyre profile as shown below:
• 
• For calculation of clearance between wheel Arch and wheel we have to create a sketch on the outer most face of the wheel and the procedure as follows.
• From the given part file we need to open in the NX cad and from the part file they give the fender and the wheel. So, now we need to check for the European regulations standard. Now we need to create the Datum plane at the outer most face of the wheel as shown in figure. A horizontal and vertical Axis is drawn from the centre of the wheel.
• The vertical axis intersection point is labelled 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 :

• 
• As per European standards, the value of 'L' should be greater than 10 mm, But section SA is less than 10 mm, so it does not satisfy at this section SA.

'L' Value at Section SB :

• 
• The value of 'L' is equal to the 10 mm, it is satisfy European standards at section SB.

'L' Value at Section SC :

• 
• The value of 'L' is less than 10 mm, it does not satisfy European standards at section SC.

'L' Value at Section SD :

• 
• The value of 'L' is less than 10 mm, it does not satisfy European standards at section SD.

'L' Value at Section SE :

• 
• The value of 'L' is less than 10 mm, it does not satisfy European standards at section SE.

• Section	L' value mm	Result
  SA	9.9489	Fail
  SB	10	Pass
  SC	-0.113949	Fail
  SD	-3.0874	Fail
  SE	-5.9973	Fail

As per the European standards, the value of 'L' should be greater than 10mm. But at Section SB, the value of L is equal to 10mm and at other sections the value of 'L' is less than 10mm.

So, it does not satisfy the condition L > 10mm to meet the European standards in any of the sections.

Wheel Guard Requirement :

Value of 'a' at SB :

• 
• The value of 'a' at the sections SB is greater than 5mm. So, it satisfies the criteria for wheel guard requirement.

Value of 'a' at SC :

• 
• The value of 'a' at the sections SC is greater than 5mm. So, it satisfies the criteria for wheel guard requirement.

Section	L' value mm	Result
SB	44.7577	Pass
SC	38.3599	Pass

The value of 'a' at the sections SB and SC are greater than 5mm. So, it satisfies the criteria for wheel guard requirement.

Conclusion :

From the above results, we can conclude that the given fender does not pass the European standards for wheel arch area.