Automotive Structure Design: Body-in-White, Crashworthiness & Lightweighting
Automotive structure design is how a vehicle’s body and frame are engineered to carry loads, protect occupants and keep weight down. These guides cover body-in-white, unibody and body-on-frame construction, steels, crashworthiness, lightweighting, sheet metal forming and the analysis methods behind them.
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Three articles that explain how a vehicle structure is built.
Body-in-White (BIW) Explained
How the structural body is welded, bonded or riveted before paint and trim.
Unibody vs. Body-on-Frame
The difference between the two construction types, with FEA rigidity data.
Why Modern Cars Keep Getting Heavier
Safety requirements, BIW reinforcement and why lightweighting matters.
Body structure & materials
Frames, roofs, steels and crash safety.
Body-on-Frame: Truck Design
How body-on-frame construction compares to unibody and how the frame vibrates.
Automotive Steel Explained
Steel types and grades and where steel is used in cars.
Automobile Roof: History & Design
How the car roof developed and how it is designed.
Crashworthiness 101
How structures reduce injuries in an impact.
Sheet metal forming
How body panels and structural parts are made.
Analysis & durability
Simulation and fatigue behavior of vehicle structures.
Frequently asked questions
What is body-in-white?
Body-in-white (BIW) is the stage of automotive manufacturing where the car’s structural body panels have been welded, bonded or riveted together, before paint, trim, glass, doors, powertrain or interior are added.
What is the difference between unibody and body-on-frame?
A unibody combines the body and frame into a single load-bearing structure. Body-on-frame bolts a separate body onto a distinct frame, which is common in trucks and some SUVs.
What is crashworthiness?
Crashworthiness is a structure’s ability to reduce the number of fatal and serious injuries in an impact. It is commonly assessed in automotive and aviation safety.
Why are modern cars getting heavier?
Safety regulations, added safety technologies and consumer expectations have led automakers to reinforce body structures and add components, which increases weight.
Prefer a simple list? See every article in the Automotive Structure Design category, or browse all categories.