Fender Design Challenge

OBJECTIVE

To design the BIW of a Fender using the fender skin data as the input data and then attach mountings on the fender for attaching it with the surrounding BIW bodies.

THEORY

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.

TYPES OF FENDER

1. Full fender type

Full fender type is traditional type of fender where more material consumption is observed. This type is used in old design of automobiles where it increases the overall weight and thus reduces performance. The maintenance also relatively more due to more surface.

2. Half fender type:

Half fender type is modern design where less material consumption is observed, so productivity increases by reducing size of blank and thus providing more performance. The maintenance also relatively low compared to full bumper type.

DIFFERENT MOUNTINGS IN THE FENDER

The fender which is designed in this project have mountings attached to it which would help the fender to fix with the adjacent components.

The mountings present on the fender are:

1. A-Pillar mounting
2. Drip Area
3. Sill mounting
4. Bumper Mounting
5. Baffle Mounting

MASTER SKETCH

PROCEDURE

DESIGNING THE A PILLAR:

• First the skin data provided by the styling team needs to be extracted.
• Then the outer edge of the fender was offset inwards to a particular length.
• Then by using the curve on surface command the unwanted portions were trimmed out using trim sheet.
• By using the law extension, the A-Pillar were extended and trimmed on the sides to get a flat edge.
• For creating a flat emboss which was used to mount the fender with the A-Pillar a datum plane was created.
• Then the required sketch was drawn on the datum plane and projected to the surface.
• Then for creating a fastener hole which needs to be around 5mm gap around it, trim surface command was used.
• Then the required blends were added using face blend and edge blend.

DESIGNING THE BUMPER MOUNTING:

• The unwanted portions were trimmed off using Curve on surface and Trim surface command.
• Then for creating a flat surfaced Emboss a datum plane was created.
• Then the required sketch drawn on the datum plane was projected to the surface and the required emboss were created.
• The holes were trimmed by using trim sheet after creating emboss.
• Emboss were created with a draft so that it satisfies the manufacturing requirements.
• Finally, the required blends were applied.

DESIGNING THE DRIP MOUNTING:

• By using the information in the master section provided the drip mounting were created.
• The drip area must be minimum 150mm apart from the front edge so that the drip mounting won't disturb the head lamp mountings.
• From backwards the drip area must be 150mm apart from the back edge to avoid the coincidence with the engine cables.
• For creating the drip area at the required distance two planes were created and then the intersection curve was used to create the curve on surface as required.
• Then the remaining unwanted portions were trimmed out.
• The design takes a vital role in avoiding the human eye seeing the insides of the car through the gap between the hood and fender.
• So, the drip area was created in particular angle as required in the master section.
• After creating the law extension as required by the master section the required emboss were created.
• For creating emboss a datum plane was generated and the sketch drawn in it was projected and the emboss feature were applied.
• Then for creating the fastener holes the trim sheet options were used.
• Then the required blends were created for improving the aesthetic of the fender.

DESIGNING THE COWL MOUNTING:

• The cowl mounting was designed to fit a splash mounting on it which helps the engine compartment to protect it from the debris that entering in to it while driving.
• For creating it three mounting areas were created with the required holes on it for the fasteners.
• For creating the holes, a datum plane was created on all three mountings and projected on to the surface.
• By selecting the required vector and deselecting the ‘project on both’ side option the holes were created.

DESIGNING THE SILL MOUNTING:

• For creating the Sill Mounting the extra portions were trimmed out.
• Then the datum was created and the required sketch was drawn and then projected.
• Then emboss were generated and blended the edges together.
• The fastener holes were created by using the trim surface feature.

FINAL MODEL

CONCLUSION

Thus, the fender was designed for the vehicle as per the requirement and all the mountings were placed at appropriate positions.