Fender Design - Wheel Arch Challenge

Fender Wheel Arch

Fender - Fender is the part of a car that protects and frames (cover) its wheels.

1 - Prevent from sand mud, rocks, liquids and other road spray from being thrown into the engine compartment and outside the car by rotating tire.

2 - And also prevent any injuries to pedestrians, and contain the motion of these particles.

3 - Also provide look to the automobile or it is a styling-oriented part.

Types Of Fenders -

1 - Full Bumper Type 2 - Half Bumper type

Note – Rear Fender is together with the body sides outer. (Or integrated), front Fender is side closing component for the engine compartment, major role of fender is to avoid chipping in the engine compartment, and also plays major role to prevent injuries for the pedestrian, Anti chipping is also a Pedestrian safety Criteria, and also covers the engine compartment so we don't see the ugly region from the outside.

“Presently conventional methodology why we are using half bumper type.”

Reason - Because for full bumper type the blank, we are using is really big and lot of wastage. But in the case of half bumper type, we have a high possibility to reduce the scrap. which means slightly increasing the blank we can produce two fenders at the same time so we also reduce the production cost and also production time this is called scrap management.

2 - Also allow to use lot of plastic on the bumper which means reduce weight so also increase the performance of the vehicle.

Mounting Reason

Wheel Arch

Question - Why we decide the wheel arch area?

Answer - Because if wheel is outside the fender, it does the more chipping and this courses lot of damage to the pedestrian and also the engine compartment, to have pedestrian safety in mind we allow to position the tire wheel inside the fender.

For Wheel Arch Design Every Region Different Regulation

Mainly three Important Regulation

1 - Japan 2 - European 3 – American

Japan Regulation

Once we get the styling data

1 – First we define the wheel center, and create a perpendicular line and that perpendicular line the point is (A), From the top view and from side view.

2 - Take the center of the wheel and make 0* to 180*

3 - Take 50* at the right of the car at the wheel center,

4 - Take 30* at the left of the vertical axis,

5 - And project on top view of fender and wheel.

6 - And at the top view the projected Point on fender and wheel minimum gap required is 5mm for Japan standard.

Question - Why fender wheel arch area very region to region?

Answer - Because it depends road condition, as we know the road condition very region to region.

European Regulation

1 - Additionally we allowed to take 150mm offset line from the zero.

2 - Make the line from the origin to the intersection line.

3 - Mark the point b/w the 150mm line to the 50* line (to take the midpoint).

4 - And draw the line from mid-point to the origin, and projection on the top view.

5 - And all these regions the length should 10.0mm,

As we know one car is lunch various region in the glove and each region have some standards so we consider one major requirement which satisfy all the regional standard, that we don't need variation in the fender.

US Regulation

1 - Do the same concept for every 10* from -20* to 180*.

2 - US have regulation there are 5mm clearance, or we say that all the clearance should we greater then,

For every region we chose European standard because it satisfies Japan and US regulation also,

For styling feedback, you will be giving drip area and also wheel arch area, for fender maintain minimum fillet of 2.5mm for improve aesthetic and remove sharpness for pedestrian safety.

We add stiffener pad for improve the NVH, in India we use stiffener pad in diesel cars, but in other region we add diesel as well as petrol, for better NVH and improve strength.

FENDER EVALUATION

1 - First level fender then we went in to full bumper type and then thinking of weight reduction and proper blank we come in to half bumper type.

2 - Some cars also have the radiator housing into the fender.

3 - Some cars have indicator in the fender and some have ORVM, when we use ORVM so we don't use indicator in the fender.

Process follows in NX CAD1 – First we create a datum plane on wheel extreme face because the extreme face of the wheel is a flat surface.

2 - Go for sketch command and select the datum plane and click ok.

3 – Then import some edges to the datum plane by project curve option.

4 – Now we create vertical and horizontal line.

5 – Create a line that is 30* from vertical axis (in 2^nd coordinate) and another line which is 50* from vertical axis (in 1^st coordinate) as we see in image.

6 – Offset the horizontal line at 150mm (upward direction).

7 – Create a line from the center and where fender curve and 150mm offset line intersect.

8 – In European standard we need another line (by divided line we get 5^th line).

9 – Then by using fender projected curve and created line we create 5^th point where projected curve and the line are intersected (SA, SB, SC, SD, SE).

10 – As we know in this challenge, we calculate the distance between the fender and wheel face (extreme face), but my sketch is created in one plane so we project the curve by the use of projected curve. (These are vertical clearance which is less then or equal to the 10mm According to European standard).

11 – By the use of wheel extreme face projected curve and the line (SA, SB, SC, SD, SE) we get five another Point (A1, A2, A3, A4, A5)

12 – And the distance between (A1 & SA), (A2 & SB), (A3 & SC), (A4 & SD), (A5 & SE) gives vertical clearance between wheel and fender and this value is greater then or equal to 5mm according to the European regulation.

13 – Then by using measuring tool we calculate the distance (Vertical and horizontal) and check these distances passes the European standard or not.

Result

The Measuring 'L' for the given wheel and fender (Horizontal clearance(L> or = 10.0mm))

1 - The Measuring 'L' for SA = 9.9490mm

2 - The Measuring 'L' for SA = 10.0mm

3 - The Measuring 'L' for SC = -0.113949mm

4 - The Measuring 'L' for SD = -2.8875mm

5 - The Measuring 'L' for SE = -5.9973mm

The Measuring 'A' for the given wheel and fender (Vertical clearance(A> or = 5.0mm))

1 - The Measuring 'A' for (A1-SA) = 30.9920mm

2 - The Measuring 'A' for (A2-SB) = 48.6263mm

3 - The Measuring 'A' for (A3-SC) = 43.3597mm

4 - The Measuring 'A' for (A4-SD) = 47.6624mm

5 - The Measuring 'A' for (A5-SE) = 52.6251mm

The Measuring 'L' for the given wheel and fender (Horizontal clearance(L> or = 10.0mm))

SR.NO.	SECTION	CLERANCE (L>=10.0mm)	RESULT
1	SA	9.9490mm	FAIL
2	SB	10.0mm	PASS
3	SC	-0.1139mm	FAIL
4	SD	-2.8875mm	FAIL
5	SE	-5.9973mm	FAIL

The Measuring 'A' for the given wheel and fender (Vertical clearance(A> or = 5.0mm))

SR.NO.	SECTION	CLERANCE(A>=5.0mm)	RESULT
1	A1-SA	30.9920mm	PASS
2	A2-SB	48.6263mm	PASS
3	A3-SC	43.3597mm	PASS
4	A4-SD	47.6634mm	PASS
5	A5-SE	52.6251mm	PASS

Conclusion

1 - We can say that the Fender does not pass the European Regulations because the minimum clearance between the fender arch to the outer most wheel is 10 mm (Horizontal clearance) and this design does not meet this minimum clearance.

2- But for vertical clearance value, all the points passes the European standard.

Neeraj Singh