Challenge

Fender Design Challenge

MMahammad Jalal15 Feb 2022

AIM: Fender Design

OBJECTIVE :
The main objective of this project is to design a fender.

INTRODUCTION :
The design of any product starts from a requirement. The design engineer sketches the product based on the requirement. Then the 2D sketch with the proper dimensions is converted into the 3D model using the advanced CAD software.Another important thing in the design is that every product that is designed should be able to manufacture. so the role of the design engineer is to design a product that can be easily manufactured and with less cost-effective.This is the place where the Design for manufacturing [DFM] and Design of assembly [DFA] take a role while developing any product. The process of development of design carries on until the design satisfies the customer's needs.Here in this
project the product that we are going to develop is a car fender.

FENDER:
The main purpose of the fender is to prevent sand, mud, rocks, liquids and other road spray from being thrown into the air by the rotating tire.

TYPES OFFENDERS:

Presently we are using the half bumper type, the reason for choosing the half bumper type is that when we choose the full bumper type the blank used for creating it is very large and also has a lot of wastage, but in the case of the half bumper type we have the possibility to reduce the scrap. This is what we called as scrap management.
In half bumper type, we reduce the usage of the steel material and uses the lots of plastic on the bumper which in term decreases the cars
weight and increases the performance.

FENDER WHEEL ARCH:

The fender wheel arch is having some standard specifications, for example, if you see the car from the front, if you see the wheel outside the fender it does more chipping and it causes lots of damage to the pedestrians and also to the car.
In order to maintain the pedestrian's safety, we have to position the tire wheel inside the fender.
For the European requirement, the clearance between the wheel and the fender's outermost skin is 5mm.
These requirements changes from country to country based upon the road conditions.

ASSEMBLY:
There are two types of assembly, they are

Bottom-up assembly
Top-down assembly
Bottom-up assembly: The bottom-up assembly is the most preferred approach for creating assembly models. In this type of assembly, the components are created in a part design workbench(As nx cad part) file. Parts are conceived in assembly design workbench using the product structure tools. After inserting each component, constraints are applied to position them properly in the 3d space with respect to the other
components. This assembly is preferred for large assemblies, especially those having intricate individual components.
Top-down assembly:
In the top assembly design approach, components are created inside the assembly design workbench. Therefore, there is no need to create separate part files of the components. This design approach is completely different from the bottom-up design approach. Here you have to
create the product file first and then one by one create all the components. Note that even then the parts are created in the product file, they are saved and opened individually one by one when they are needed. Here the construction and the assembly take place simultaneously.

MOUNTING REGIONS ON FENDER:

There are 5 mounting regions on the fender, they are:

1. A-pillar mounting
2. Body mounting
3. Sill mounting
4. Bumper mounting
5. Drip mounting

DESIGN METHODOLOGY:
GIVEN DATA:

DESIGN 0F DRIP AREA MOUNTING :
It is the important mounting uni of the fender. it is connected with the engine compartment, therefore a lot of design constraints are to be
followed while designing the fender.
While designing the drip area we have to initially leave 200-300 mm for the cowl top
For placing the headlamp we have to leave at least 150 mm at the front while designing the fender
The cowl's top part consists of a wiper motor and its instruments.

Two darts are added on the longer side of the drip area in order to provide stiffness and add strength to the part. This helps the fender to
not to vibrate and impact the forces outside of the fender during the motion of the vehicle.Embossing is provided on the mounting to strengthen
them during fastening.

DESIGN OF SILL MOUNTING AREA:
Sill is the panel directly below the bottom of the door supporting the floor and may be used to combine the floor and the body. The bottom
end of the fender is mounted on the sill body for reinforcement of the fender panel, thus the sill mounting position is designed with holes and
emboss.M5 fasteners are used to fix the fenders on the sill body.

DESIGN OF BUMPER MOUNTING AREA:
A bumper mounting area is used to fix the plastic bumper to the fender with the help of the fasteners.

DESIGN OF A-PILLAR MOUNTING AREA:
The A-pillar is the structural pillar that combines the body with the roof. this makes the sides of the windshield rest. front fenders are fastened to
the A-pillar to form a robust structure.

DESIGN OF BAFFLE MOUNTING AREA:
Baffle mounting or mudguard are clip fit types of mounting on the inner side of the fender arch over the Tyre.it protects the car engine
compartment and pedestrians from causing injuries from chip out debris on the road when the car is in motion. They are mounted on the fender
using a special type of locking clips that are made up of plastics.