Fender Design - Wheel Arch Challenge

Wheel Arch Calculations

From:Sahil Parab

Aim :

To calculate the wheel arch gap at required points and check whether the car passes the European standard.

Objective :

• Study about the different wheel arch gap standards.
• Check the feasibility for the European standard.
• Measure the distance at each angles and mention given model is pass or fail.

Theory :

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.

Fender Wheel Arch Regulations :

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.

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.

US 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.

Wheel Arch calculations.

Firstly createa datum plane on ht eoutermost surface of the wheel.

Net draw your lines and constraints as per the regulations and constrain them.

After completing the drawing, we have check for a and l values.

'a' value calculation of SB-SB

SC-SC "a" value calcultion

For calculations of "l" value, the same is demonstrated.

standards :

• "a" should be more than 5mm at line 30degree forward and 50degree.
• "L" should be greater than 10mm

Conclusion:

The fender does not pass through European Standards as the minimum clearance require is 10mm.