Hood design-Week 2

01) Title :- HOOD DESIGN

02) Objectives

Designing Hood outer panel, inner panel and the necessary reinforcements by using given Master section & skin Surface.

03) Requirements

• Outer Panel Thickness :- 0.75mm
• Inner Panel Thickness :- 0.75mm
• Master Sections
• Skin Surface

04) Introduction

*) The Hood or the Bonnet is the Hinged cover over the engine of motor vehicles. Hood can open to allow access to the engine compartmemt.

*) Hoods are typically made out of the same material as Steel, Aluminium, Fiber glass or Carbon Fiber.

Pedestrain Safety Design

*) Vehicle safety factors should simultaneously consider occupant and pedestrian safety, given that pedestrians are the third largest category of traffic fatalities. Most pedestrian deaths occur due to traumatic brain injury, resulting from the hard impact of the human head against the vehicle's stiff hood or windshield.

*) Therefore, how to design a pedestrian-friendly vehicle and propose a new hood structure is a matter of urgency for minimising pedestrian head injuries. In this study, three kinds of sandwich hood structures are proposed for reducing pedestrian head injuries, including carbon fibre-reinforced polycarbonate, carbon fibre-reinforced foam and aluminium-reinforced polycarbonate.

*) The potential of crash avoidance systems to reduce pedestrian deaths has been highlighted by Global NCAP at the United Nations in New York. Speaking to the UN Road safety Collaboration, Global NCAP’s Secretary General, David Ward said that emergency braking systems combined with softer car fronts can reverse the rise in pedestrian fatalities.

05) Hood Components

1. Hood Outer Panel
2. Hood Inner Panel
3. Latch & Striker
4. Hinges
5. Stiffner Pad
6. Mastic Seal

06) Design Considerations for Hood Design

• NVH
• 10-15mm gap between Hood & bumper to access the secondary lock lever
• Opening Angle Position / Hood Balancer Mounting
• Latch & Striker pointing
• Hinge Axis
• Striker Trajectory Circle
• Pedastrain rating / Euro NCAP Regulations

07) Procedure

*) Create inner panel from given Skin surface & master Section

*) Create emboses for strengthening of inner panel as per design guide rules

*) Emboses should be designed in such a way that the force applied on the hood should travel towards outside.

*) Also Create Emboses for the reinforcement parts like Hinges, Latch & Striker

*) Following are the images of Hood inner panel created.

*) Thicken the given skin surface to get Hood outer Panel

*) Assemble the Hinges at their position

*) Draw Trajectory circle to posion Latch & Striker

*) Assemble the Latch at the specified position

*) Heming

*) Create heming to assemble both Hood Inner & Outer Panel

*) Different View modes

*) Tree Structure