Body
Design Factors
TEC452 Home
Body Engineering Index
Body
Components
Body Design Factors
Unitized B-I-W
Hydroforming
Vibration and Noise
High-Strength Steel Design Guidelines
Glass Design
Neon B-I-W Case Study
Rigidity
- High torsional and bending rigidity
- Must minimize the elastic deformation of the apertures
- Rigidity must be balanced with the vibrational characteristics
Vibrational
Characteristics
- Must consider the body and its components
- Causes of vibration
- Wheels & Suspension
- Powertrain
Wind
Natural frequency tuning
- Creasing of walls
- Sheet metal thickness
- Cross sections
Operational Integrity
- Alternating stresses can cause damage
- Alternating stresses caused by
- Road conditions
- Driving conditions
- Certain body areas are more susceptible
- Engine mounts
- Suspension/steering mounts
Crash Worthiness
- Protection of the occupants and vehicle interior in high speed collisions
- Kinetic energy must be absorbed via controlled body panel deformation
Ease of Repair
- Easy replacement of body parts
- Most susceptible to damage
- Most susceptible to wear
- Easy access to interior panels
- Easy access to bolts and joints
- Feature lines for repainting the individual panels
Materials
- Sheet steel
- 0.6 to 3.0 mm gage
- Possesses ideal properties
stiffness
- strength
- ductility
- formability
- availability
- cost
High-Strength Low-Alloy Steel (HSLA)Used for highly stressed areas
Allows for reduction in thickness
- Aluminum
- Primarily used for weight reduction (1/3 of steel)
- Used for hoods, trunk lids, roofs
- Not very economical (~ 3x the cost of steel)
- In common use among German luxury vehicles
- Aluminum alloys can surpass steel in mechanical properties
- Plastics
- Used in a limited number of components
Load bearing components use reinforced thermoplastics
Energy absorbing components use polyurethane and polypropylene
Body components (e.g. roof, door) use polypropylene, polyethylene, polycarbonates …
May present cost, weight, and durability benefits
Safety
- Protection for multiple purposes
- Occupants
- Pedestrians
- The vehicle
- Exterior bodyBody deformation
- Body shape
Injury Risk
Factors
- Exterior body safety factors
Moveable lamps
Moveable mirrors
Recessed door handles
- Interior body panels
- Add rigidity
- A, B, C pillars
- Floor panels
Control deformation behavior
- Inner hood panel’s crush initiators
- Side member crush direction
Aerodynamics
- Minimize drag
- Maximize down force
- Minimize side force
- Minimize wind noise
- Minimize vibration
TEC452 Home
Body Engineering Index
Body
Components
Body Design Factors
Unitized B-I-W
Hydroforming
Vibration and Noise
High-Strength Steel Design Guidelines
Glass Design
Neon B-I-W Case Study